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4. Use [code] tags to format code blocks. |
On April 27 2016 05:44 Ropid wrote:I think the whole thing is then this (not sure): ++*s++;
++*(s++);
++*s;
s++;
++(*s);
s++;
*s += 1;
s += 1;
Pretty sure you're right, which means I was definitely wrong 
I honestly consider myself a pretty strong C programmer and I would never have said the different forms of '++' have different precedence... that makes that line even more ridiculous :D
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Can I just say that code looks bloody awful. RIP manitou
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On April 27 2016 06:07 Manit0u wrote:+ Show Spoiler +Lemme put this in perspective:
char *
dtoa
#ifdef KR_headers
(dd, mode, ndigits, decpt, sign, rve)
double dd; int mode, ndigits, *decpt, *sign; char **rve;
#else
(double dd, int mode, int ndigits, int *decpt, int *sign, char **rve)
#endif
{
/* Arguments ndigits, decpt, sign are similar to those
of ecvt and fcvt; trailing zeros are suppressed from
the returned string. If not null, *rve is set to point
to the end of the return value. If d is +-Infinity or NaN,
then *decpt is set to 9999.
mode:
0 ==> shortest string that yields d when read in
and rounded to nearest.
1 ==> like 0, but with Steele & White stopping rule;
e.g. with IEEE P754 arithmetic , mode 0 gives
1e23 whereas mode 1 gives 9.999999999999999e22.
2 ==> max(1,ndigits) significant digits. This gives a
return value similar to that of ecvt, except
that trailing zeros are suppressed.
3 ==> through ndigits past the decimal point. This
gives a return value similar to that from fcvt,
except that trailing zeros are suppressed, and
ndigits can be negative.
4,5 ==> similar to 2 and 3, respectively, but (in
round-nearest mode) with the tests of mode 0 to
possibly return a shorter string that rounds to d.
With IEEE arithmetic and compilation with
-DHonor_FLT_ROUNDS, modes 4 and 5 behave the same
as modes 2 and 3 when FLT_ROUNDS != 1.
6-9 ==> Debugging modes similar to mode - 4: don't try
fast floating-point estimate (if applicable).
Values of mode other than 0-9 are treated as mode 0.
Sufficient space is allocated to the return value
to hold the suppressed trailing zeros.
*/
int bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1,
j, j1, k, k0, k_check, leftright, m2, m5, s2, s5,
spec_case, try_quick;
Long L;
#ifndef Sudden_Underflow
int denorm;
ULong x;
#endif
Bigint *b, *b1, *delta, *mlo, *mhi, *S;
U d2, eps, u;
double ds;
char *s, *s0;
#ifndef No_leftright
#ifdef IEEE_Arith
U eps1;
#endif
#endif
#ifdef SET_INEXACT
int inexact, oldinexact;
#endif
#ifdef Honor_FLT_ROUNDS /*{*/
int Rounding;
#ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
Rounding = Flt_Rounds;
#else /*}{*/
Rounding = 1;
switch(fegetround()) {
case FE_TOWARDZERO: Rounding = 0; break;
case FE_UPWARD: Rounding = 2; break;
case FE_DOWNWARD: Rounding = 3;
}
#endif /*}}*/
#endif /*}*/
#ifndef MULTIPLE_THREADS
if (dtoa_result) {
freedtoa(dtoa_result);
dtoa_result = 0;
}
#endif
u.d = dd;
if (word0(&u) & Sign_bit) {
/* set sign for everything, including 0's and NaNs */
*sign = 1;
word0(&u) &= ~Sign_bit; /* clear sign bit */
}
else
*sign = 0;
#if defined(IEEE_Arith) + defined(VAX)
#ifdef IEEE_Arith
if ((word0(&u) & Exp_mask) == Exp_mask)
#else
if (word0(&u) == 0x8000)
#endif
{
/* Infinity or NaN */
*decpt = 9999;
#ifdef IEEE_Arith
if (!word1(&u) && !(word0(&u) & 0xfffff))
return nrv_alloc("Infinity", rve, 8);
#endif
return nrv_alloc("NaN", rve, 3);
}
#endif
#ifdef IBM
dval(&u) += 0; /* normalize */
#endif
if (!dval(&u)) {
*decpt = 1;
return nrv_alloc("0", rve, 1);
}
#ifdef SET_INEXACT
try_quick = oldinexact = get_inexact();
inexact = 1;
#endif
#ifdef Honor_FLT_ROUNDS
if (Rounding >= 2) {
if (*sign)
Rounding = Rounding == 2 ? 0 : 2;
else
if (Rounding != 2)
Rounding = 0;
}
#endif
b = d2b(&u, &be, &bbits);
#ifdef Sudden_Underflow
i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
#else
if ((i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
#endif
dval(&d2) = dval(&u);
word0(&d2) &= Frac_mask1;
word0(&d2) |= Exp_11;
#ifdef IBM
if (j = 11 - hi0bits(word0(&d2) & Frac_mask))
dval(&d2) /= 1 << j;
#endif
/* log(x) ~=~ log(1.5) + (x-1.5)/1.5
* log10(x) = log(x) / log(10)
* ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
* log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
*
* This suggests computing an approximation k to log10(d) by
*
* k = (i - Bias)*0.301029995663981
* + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
*
* We want k to be too large rather than too small.
* The error in the first-order Taylor series approximation
* is in our favor, so we just round up the constant enough
* to compensate for any error in the multiplication of
* (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
* and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
* adding 1e-13 to the constant term more than suffices.
* Hence we adjust the constant term to 0.1760912590558.
* (We could get a more accurate k by invoking log10,
* but this is probably not worthwhile.)
*/
i -= Bias;
#ifdef IBM
i <<= 2;
i += j;
#endif
#ifndef Sudden_Underflow
denorm = 0;
}
else {
/* d is denormalized */
i = bbits + be + (Bias + (P-1) - 1);
x = i > 32 ? word0(&u) << (64 - i) | word1(&u) >> (i - 32)
: word1(&u) << (32 - i);
dval(&d2) = x;
word0(&d2) -= 31*Exp_msk1; /* adjust exponent */
i -= (Bias + (P-1) - 1) + 1;
denorm = 1;
}
#endif
ds = (dval(&d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
k = (int)ds;
if (ds < 0. && ds != k)
k--; /* want k = floor(ds) */
k_check = 1;
if (k >= 0 && k <= Ten_pmax) {
if (dval(&u) < tens[k]
k--;
k_check = 0;
}
j = bbits - i - 1;
if (j >= 0) {
b2 = 0;
s2 = j;
}
else {
b2 = -j;
s2 = 0;
}
if (k >= 0) {
b5 = 0;
s5 = k;
s2 += k;
}
else {
b2 -= k;
b5 = -k;
s5 = 0;
}
if (mode < 0 || mode > 9)
mode = 0;
#ifndef SET_INEXACT
#ifdef Check_FLT_ROUNDS
try_quick = Rounding == 1;
#else
try_quick = 1;
#endif
#endif /*SET_INEXACT*/
if (mode > 5) {
mode -= 4;
try_quick = 0;
}
leftright = 1;
ilim = ilim1 = -1; /* Values for cases 0 and 1; done here to */
/* silence erroneous "gcc -Wall" warning. */
switch(mode) {
case 0:
case 1:
i = 18;
ndigits = 0;
break;
case 2:
leftright = 0;
/* no break */
case 4:
if (ndigits <= 0)
ndigits = 1;
ilim = ilim1 = i = ndigits;
break;
case 3:
leftright = 0;
/* no break */
case 5:
i = ndigits + k + 1;
ilim = i;
ilim1 = i - 1;
if (i <= 0)
i = 1;
}
s = s0 = rv_alloc(i);
#ifdef Honor_FLT_ROUNDS
if (mode > 1 && Rounding != 1)
leftright = 0;
#endif
if (ilim >= 0 && ilim <= Quick_max && try_quick) {
/* Try to get by with floating-point arithmetic. */
i = 0;
dval(&d2) = dval(&u);
k0 = k;
ilim0 = ilim;
ieps = 2; /* conservative */
if (k > 0) {
ds = tens[k&0xf];
j = k >> 4;
if (j & Bletch) {
/* prevent overflows */
j &= Bletch - 1;
dval(&u) /= bigtens[n_bigtens-1];
ieps++;
}
for(; j; j >>= 1, i++)
if (j & 1) {
ieps++;
ds *= bigtens[i];
}
dval(&u) /= ds;
}
else if ((j1 = -k)) {
dval(&u) *= tens[j1 & 0xf];
for(j = j1 >> 4; j; j >>= 1, i++)
if (j & 1) {
ieps++;
dval(&u) *= bigtens[i];
}
}
if (k_check && dval(&u) < 1. && ilim > 0) {
if (ilim1 <= 0)
goto fast_failed;
ilim = ilim1;
k--;
dval(&u) *= 10.;
ieps++;
}
dval(&eps) = ieps*dval(&u) + 7.;
word0(&eps) -= (P-1)*Exp_msk1;
if (ilim == 0) {
S = mhi = 0;
dval(&u) -= 5.;
if (dval(&u) > dval(&eps))
goto one_digit;
if (dval(&u) < -dval(&eps))
goto no_digits;
goto fast_failed;
}
#ifndef No_leftright
if (leftright) {
/* Use Steele & White method of only
* generating digits needed.
*/
dval(&eps) = 0.5/tens[ilim-1] - dval(&eps);
#ifdef IEEE_Arith
if (k0 < 0 && j1 >= 307) {
eps1.d = 1.01e256; /* 1.01 allows roundoff in the next few lines */
word0(&eps1) -= Exp_msk1 * (Bias+P-1);
dval(&eps1) *= tens[j1 & 0xf];
for(i = 0, j = (j1-256) >> 4; j; j >>= 1, i++)
if (j & 1)
dval(&eps1) *= bigtens[i];
if (eps.d < eps1.d)
eps.d = eps1.d;
}
#endif
for(i = 0; {
L = dval(&u);
dval(&u) -= L;
*s++ = '0' + (int)L;
if (1. - dval(&u) < dval(&eps))
goto bump_up;
if (dval(&u) < dval(&eps))
goto ret1;
if (++i >= ilim)
break;
dval(&eps) *= 10.;
dval(&u) *= 10.;
}
}
else {
#endif
/* Generate ilim digits, then fix them up. */
dval(&eps) *= tens[ilim-1];
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u));
if (!(dval(&u) -= L))
ilim = i;
*s++ = '0' + (int)L;
if (i == ilim) {
if (dval(&u) > 0.5 + dval(&eps))
goto bump_up;
else if (dval(&u) < 0.5 - dval(&eps)) {
while(*--s == '0');
s++;
goto ret1;
}
break;
}
}
#ifndef No_leftright
}
#endif
fast_failed:
s = s0;
dval(&u) = dval(&d2);
k = k0;
ilim = ilim0;
}
/* Do we have a "small" integer? */
if (be >= 0 && k <= Int_max) {
/* Yes. */
ds = tens[k];
if (ndigits < 0 && ilim <= 0) {
S = mhi = 0;
if (ilim < 0 || dval(&u) <= 5*ds)
goto no_digits;
goto one_digit;
}
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u) / ds);
dval(&u) -= L*ds;
#ifdef Check_FLT_ROUNDS
/* If FLT_ROUNDS == 2, L will usually be high by 1 */
if (dval(&u) < 0) {
L--;
dval(&u) += ds;
}
#endif
*s++ = '0' + (int)L;
if (!dval(&u)) {
#ifdef SET_INEXACT
inexact = 0;
#endif
break;
}
if (i == ilim) {
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto ret1;
case 2: goto bump_up;
}
#endif
dval(&u) += dval(&u);
#ifdef ROUND_BIASED
if (dval(&u) >= ds)
#else
if (dval(&u) > ds || (dval(&u) == ds && L & 1))
#endif
{
bump_up:
while(*--s == '9')
if (s == s0) {
k++;
*s = '0';
break;
}
++*s++;
}
break;
}
}
goto ret1;
}
m2 = b2;
m5 = b5;
mhi = mlo = 0;
if (leftright) {
i =
#ifndef Sudden_Underflow
denorm ? be + (Bias + (P-1) - 1 + 1) :
#endif
#ifdef IBM
1 + 4*P - 3 - bbits + ((bbits + be - 1) & 3);
#else
1 + P - bbits;
#endif
b2 += i;
s2 += i;
mhi = i2b(1);
}
if (m2 > 0 && s2 > 0) {
i = m2 < s2 ? m2 : s2;
b2 -= i;
m2 -= i;
s2 -= i;
}
if (b5 > 0) {
if (leftright) {
if (m5 > 0) {
mhi = pow5mult(mhi, m5);
b1 = mult(mhi, b);
Bfree(b);
b = b1;
}
if ((j = b5 - m5))
b = pow5mult(b, j);
}
else
b = pow5mult(b, b5);
}
S = i2b(1);
if (s5 > 0)
S = pow5mult(S, s5);
/* Check for special case that d is a normalized power of 2. */
spec_case = 0;
if ((mode < 2 || leftright)
#ifdef Honor_FLT_ROUNDS
&& Rounding == 1
#endif
) {
if (!word1(&u) && !(word0(&u) & Bndry_mask)
#ifndef Sudden_Underflow
&& word0(&u) & (Exp_mask & ~Exp_msk1)
#endif
) {
/* The special case */
b2 += Log2P;
s2 += Log2P;
spec_case = 1;
}
}
/* Arrange for convenient computation of quotients:
* shift left if necessary so divisor has 4 leading 0 bits.
*
* Perhaps we should just compute leading 28 bits of S once
* and for all and pass them and a shift to quorem, so it
* can do shifts and ors to compute the numerator for q.
*/
i = dshift(S, s2);
b2 += i;
m2 += i;
s2 += i;
if (b2 > 0)
b = lshift(b, b2);
if (s2 > 0)
S = lshift(S, s2);
if (k_check) {
if (cmp(b,S) < 0) {
k--;
b = multadd(b, 10, 0); /* we botched the k estimate */
if (leftright)
mhi = multadd(mhi, 10, 0);
ilim = ilim1;
}
}
if (ilim <= 0 && (mode == 3 || mode == 5)) {
if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) {
/* no digits, fcvt style */
no_digits:
k = -1 - ndigits;
goto ret;
}
one_digit:
*s++ = '1';
k++;
goto ret;
}
if (leftright) {
if (m2 > 0)
mhi = lshift(mhi, m2);
/* Compute mlo -- check for special case
* that d is a normalized power of 2.
*/
mlo = mhi;
if (spec_case) {
mhi = Balloc(mhi->k);
Bcopy(mhi, mlo);
mhi = lshift(mhi, Log2P);
}
for(i = 1;;i++) {
dig = quorem(b,S) + '0';
/* Do we yet have the shortest decimal string
* that will round to d?
*/
j = cmp(b, mlo);
delta = diff(S, mhi);
j1 = delta->sign ? 1 : cmp(b, delta);
Bfree(delta);
#ifndef ROUND_BIASED
if (j1 == 0 && mode != 1 && !(word1(&u) & 1)
#ifdef Honor_FLT_ROUNDS
&& Rounding >= 1
#endif
) {
if (dig == '9')
goto round_9_up;
if (j > 0)
dig++;
#ifdef SET_INEXACT
else if (!b->x[0] && b->wds <= 1)
inexact = 0;
#endif
*s++ = dig;
goto ret;
}
#endif
if (j < 0 || (j == 0 && mode != 1
#ifndef ROUND_BIASED
&& !(word1(&u) & 1)
#endif
)) {
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto accept_dig;
}
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto accept_dig;
case 2: goto keep_dig;
}
#endif /*Honor_FLT_ROUNDS*/
if (j1 > 0) {
b = lshift(b, 1);
j1 = cmp(b, S);
#ifdef ROUND_BIASED
if (j1 >= 0 /*)*/
#else
if ((j1 > 0 || (j1 == 0 && dig & 1))
#endif
&& dig++ == '9')
goto round_9_up;
}
accept_dig:
*s++ = dig;
goto ret;
}
if (j1 > 0) {
#ifdef Honor_FLT_ROUNDS
if (!Rounding)
goto accept_dig;
#endif
if (dig == '9') { /* possible if i == 1 */
round_9_up:
*s++ = '9';
goto roundoff;
}
*s++ = dig + 1;
goto ret;
}
#ifdef Honor_FLT_ROUNDS
keep_dig:
#endif
*s++ = dig;
if (i == ilim)
break;
b = multadd(b, 10, 0);
if (mlo == mhi)
mlo = mhi = multadd(mhi, 10, 0);
else {
mlo = multadd(mlo, 10, 0);
mhi = multadd(mhi, 10, 0);
}
}
}
else
for(i = 1;; i++) {
*s++ = dig = quorem(b,S) + '0';
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto ret;
}
if (i >= ilim)
break;
b = multadd(b, 10, 0);
}
/* Round off last digit */
#ifdef Honor_FLT_ROUNDS
switch(Rounding) {
case 0: goto trimzeros;
case 2: goto roundoff;
}
#endif
b = lshift(b, 1);
j = cmp(b, S);
#ifdef ROUND_BIASED
if (j >= 0)
#else
if (j > 0 || (j == 0 && dig & 1))
#endif
{
roundoff:
while(*--s == '9')
if (s == s0) {
k++;
*s++ = '1';
goto ret;
}
++*s++;
}
else {
#ifdef Honor_FLT_ROUNDS
trimzeros:
#endif
while(*--s == '0');
s++;
}
ret:
Bfree(S);
if (mhi) {
if (mlo && mlo != mhi)
Bfree(mlo);
Bfree(mhi);
}
ret1:
#ifdef SET_INEXACT
if (inexact) {
if (!oldinexact) {
word0(&u) = Exp_1 + (70 << Exp_shift);
word1(&u) = 0;
dval(&u) += 1.;
}
}
else if (!oldinexact)
clear_inexact();
#endif
Bfree(b);
*s = 0;
*decpt = k + 1;
if (rve)
*rve = s;
return s0;
}
#ifdef __cplusplus
}
#endif
The thing is variable s is actually a char* so a string... This code is such a mess to read through.
Just no.
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On April 27 2016 08:23 solidbebe wrote:
Can I just say that code looks bloody awful. RIP manitou
Don't be sorry for me. I don't have to work with it or anything. Just stumbled upon it after seeing how much discussion you can find about it on the Internet. I'm quite surprised though that it's being used in numerous applications (being a rather important part of them none the less) and no one has bothered to make some cleaner version of it for 30 years. It really baffles me.
Edit:
It won't leave me be 
int print_r(char *s);
int main(void)
{
char *s = "12345678";
int i = 0;
++*s;
s++;
printf("sizeof: %d, strlen: %d\n", sizeof(s) / sizeof(char), strlen(s));
print_r(s);
return 0;
}
int print_r(char *s)
{
int i;
for (i = 0; i < strlen(s); i++) {
printf("%c\n", s[i]);
}
}
Output:
sizeof: 4, strlen: 7
2
3
4
5
6
7
8
Could someone please make some sense out of it? How can it have 4 and 7 characters at the same time?
|
Making some assumptions, but
sizeof(s) is sizeof the variable s, a char pointer, which is the same as any pointer, and is usually 32 bits (or 64) in size
sizeof(char) is sizeof a char, which is usually the size of a byte, or 8 bits
32/8 is 4
strlen starts from the beginning of the char array and counts until it reaches a \0, which is 7 because you messed around with the char array pointer.
|
Folks, looking for a bit of help with mean.io. I dled and installed node, mongodb and git. I then init a directory and run npm install inside of it. I then run gulp to start the server. This throws errors that I'm missing various modules such as 'mongoose', 'async', etc. but these should be installed from the npm install, correct? The exact error is + Show Spoiler +E:\mean_workspace\monoprobability\node_modules\q\q.js:155
throw e;
^
Error: Cannot find module 'mongoose'
at Function.Module._resolveFilename (module.js:325:15)
at Function.Module._load (module.js:276:25)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\server\models\user.js:6:17)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at requireModel (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:116:19)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:21:7
at Array.forEach (native)
at walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:23:7
at Array.forEach (native)
at Object.walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at MeanUserKlass.Module (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:134:14)
at new MeanUserKlass (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:10:10)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:21:16)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Module.activate (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\dependablelist.js:52:15)
When I tried to start using mean.io on another computer it worked fine so it is almost certainly a problem with my current environment. When I look inside of my root's node_modules folder it is missing both 'async' and 'mongoose'. Are they supposed to be in that folder?
|
On April 27 2016 10:03 Blisse wrote:
Making some assumptions, but
sizeof(s) is sizeof the variable s, a char pointer, which is the same as any pointer, and is usually 32 bits (or 64) in size
sizeof(char) is sizeof a char, which is usually the size of a byte, or 8 bits
32/8 is 4
strlen starts from the beginning of the char array and counts until it reaches a \0, which is 7 because you messed around with the char array pointer.
As Blisse said. sizeof returns the size of the variable. The *s is a pointer, pointer size in memory is 4 bytes regardless of what it points to, so whether it was pointing to char / int / double / void... etc, the size of the pointer variable will always be 4. Also, the sizeof returns the size in bytes not bits. So it is the same as Blisse said except it will be 4/1=4 not 32/8=4.
Also same for the strlen, in your code you changed the position of the s pointer forward by one byte (since it points to a char, any increment in pointer variable will increment one byte). It started counting from the second element which is '2' and continued until it reached the null.
|
On April 27 2016 10:03 Blisse wrote:
Making some assumptions, but
sizeof(s) is sizeof the variable s, a char pointer, which is the same as any pointer, and is usually 32 bits (or 64) in size
sizeof(char) is sizeof a char, which is usually the size of a byte, or 8 bits
32/8 is 4
strlen starts from the beginning of the char array and counts until it reaches a \0, which is 7 because you messed around with the char array pointer.
edit: Nvm, it's probably incrementing the 1 to 2 at the location of the pointer.
|
On April 27 2016 06:07 Manit0u wrote:Lemme put this in perspective: + Show Spoiler +
char *
dtoa
#ifdef KR_headers
(dd, mode, ndigits, decpt, sign, rve)
double dd; int mode, ndigits, *decpt, *sign; char **rve;
#else
(double dd, int mode, int ndigits, int *decpt, int *sign, char **rve)
#endif
{
/* Arguments ndigits, decpt, sign are similar to those
of ecvt and fcvt; trailing zeros are suppressed from
the returned string. If not null, *rve is set to point
to the end of the return value. If d is +-Infinity or NaN,
then *decpt is set to 9999.
mode:
0 ==> shortest string that yields d when read in
and rounded to nearest.
1 ==> like 0, but with Steele & White stopping rule;
e.g. with IEEE P754 arithmetic , mode 0 gives
1e23 whereas mode 1 gives 9.999999999999999e22.
2 ==> max(1,ndigits) significant digits. This gives a
return value similar to that of ecvt, except
that trailing zeros are suppressed.
3 ==> through ndigits past the decimal point. This
gives a return value similar to that from fcvt,
except that trailing zeros are suppressed, and
ndigits can be negative.
4,5 ==> similar to 2 and 3, respectively, but (in
round-nearest mode) with the tests of mode 0 to
possibly return a shorter string that rounds to d.
With IEEE arithmetic and compilation with
-DHonor_FLT_ROUNDS, modes 4 and 5 behave the same
as modes 2 and 3 when FLT_ROUNDS != 1.
6-9 ==> Debugging modes similar to mode - 4: don't try
fast floating-point estimate (if applicable).
Values of mode other than 0-9 are treated as mode 0.
Sufficient space is allocated to the return value
to hold the suppressed trailing zeros.
*/
int bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1,
j, j1, k, k0, k_check, leftright, m2, m5, s2, s5,
spec_case, try_quick;
Long L;
#ifndef Sudden_Underflow
int denorm;
ULong x;
#endif
Bigint *b, *b1, *delta, *mlo, *mhi, *S;
U d2, eps, u;
double ds;
char *s, *s0;
#ifndef No_leftright
#ifdef IEEE_Arith
U eps1;
#endif
#endif
#ifdef SET_INEXACT
int inexact, oldinexact;
#endif
#ifdef Honor_FLT_ROUNDS /*{*/
int Rounding;
#ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
Rounding = Flt_Rounds;
#else /*}{*/
Rounding = 1;
switch(fegetround()) {
case FE_TOWARDZERO: Rounding = 0; break;
case FE_UPWARD: Rounding = 2; break;
case FE_DOWNWARD: Rounding = 3;
}
#endif /*}}*/
#endif /*}*/
#ifndef MULTIPLE_THREADS
if (dtoa_result) {
freedtoa(dtoa_result);
dtoa_result = 0;
}
#endif
u.d = dd;
if (word0(&u) & Sign_bit) {
/* set sign for everything, including 0's and NaNs */
*sign = 1;
word0(&u) &= ~Sign_bit; /* clear sign bit */
}
else
*sign = 0;
#if defined(IEEE_Arith) + defined(VAX)
#ifdef IEEE_Arith
if ((word0(&u) & Exp_mask) == Exp_mask)
#else
if (word0(&u) == 0x8000)
#endif
{
/* Infinity or NaN */
*decpt = 9999;
#ifdef IEEE_Arith
if (!word1(&u) && !(word0(&u) & 0xfffff))
return nrv_alloc("Infinity", rve, 8);
#endif
return nrv_alloc("NaN", rve, 3);
}
#endif
#ifdef IBM
dval(&u) += 0; /* normalize */
#endif
if (!dval(&u)) {
*decpt = 1;
return nrv_alloc("0", rve, 1);
}
#ifdef SET_INEXACT
try_quick = oldinexact = get_inexact();
inexact = 1;
#endif
#ifdef Honor_FLT_ROUNDS
if (Rounding >= 2) {
if (*sign)
Rounding = Rounding == 2 ? 0 : 2;
else
if (Rounding != 2)
Rounding = 0;
}
#endif
b = d2b(&u, &be, &bbits);
#ifdef Sudden_Underflow
i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
#else
if ((i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
#endif
dval(&d2) = dval(&u);
word0(&d2) &= Frac_mask1;
word0(&d2) |= Exp_11;
#ifdef IBM
if (j = 11 - hi0bits(word0(&d2) & Frac_mask))
dval(&d2) /= 1 << j;
#endif
/* log(x) ~=~ log(1.5) + (x-1.5)/1.5
* log10(x) = log(x) / log(10)
* ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
* log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
*
* This suggests computing an approximation k to log10(d) by
*
* k = (i - Bias)*0.301029995663981
* + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
*
* We want k to be too large rather than too small.
* The error in the first-order Taylor series approximation
* is in our favor, so we just round up the constant enough
* to compensate for any error in the multiplication of
* (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
* and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
* adding 1e-13 to the constant term more than suffices.
* Hence we adjust the constant term to 0.1760912590558.
* (We could get a more accurate k by invoking log10,
* but this is probably not worthwhile.)
*/
i -= Bias;
#ifdef IBM
i <<= 2;
i += j;
#endif
#ifndef Sudden_Underflow
denorm = 0;
}
else {
/* d is denormalized */
i = bbits + be + (Bias + (P-1) - 1);
x = i > 32 ? word0(&u) << (64 - i) | word1(&u) >> (i - 32)
: word1(&u) << (32 - i);
dval(&d2) = x;
word0(&d2) -= 31*Exp_msk1; /* adjust exponent */
i -= (Bias + (P-1) - 1) + 1;
denorm = 1;
}
#endif
ds = (dval(&d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
k = (int)ds;
if (ds < 0. && ds != k)
k--; /* want k = floor(ds) */
k_check = 1;
if (k >= 0 && k <= Ten_pmax) {
if (dval(&u) < tens[k]
k--;
k_check = 0;
}
j = bbits - i - 1;
if (j >= 0) {
b2 = 0;
s2 = j;
}
else {
b2 = -j;
s2 = 0;
}
if (k >= 0) {
b5 = 0;
s5 = k;
s2 += k;
}
else {
b2 -= k;
b5 = -k;
s5 = 0;
}
if (mode < 0 || mode > 9)
mode = 0;
#ifndef SET_INEXACT
#ifdef Check_FLT_ROUNDS
try_quick = Rounding == 1;
#else
try_quick = 1;
#endif
#endif /*SET_INEXACT*/
if (mode > 5) {
mode -= 4;
try_quick = 0;
}
leftright = 1;
ilim = ilim1 = -1; /* Values for cases 0 and 1; done here to */
/* silence erroneous "gcc -Wall" warning. */
switch(mode) {
case 0:
case 1:
i = 18;
ndigits = 0;
break;
case 2:
leftright = 0;
/* no break */
case 4:
if (ndigits <= 0)
ndigits = 1;
ilim = ilim1 = i = ndigits;
break;
case 3:
leftright = 0;
/* no break */
case 5:
i = ndigits + k + 1;
ilim = i;
ilim1 = i - 1;
if (i <= 0)
i = 1;
}
s = s0 = rv_alloc(i);
#ifdef Honor_FLT_ROUNDS
if (mode > 1 && Rounding != 1)
leftright = 0;
#endif
if (ilim >= 0 && ilim <= Quick_max && try_quick) {
/* Try to get by with floating-point arithmetic. */
i = 0;
dval(&d2) = dval(&u);
k0 = k;
ilim0 = ilim;
ieps = 2; /* conservative */
if (k > 0) {
ds = tens[k&0xf];
j = k >> 4;
if (j & Bletch) {
/* prevent overflows */
j &= Bletch - 1;
dval(&u) /= bigtens[n_bigtens-1];
ieps++;
}
for(; j; j >>= 1, i++)
if (j & 1) {
ieps++;
ds *= bigtens[i];
}
dval(&u) /= ds;
}
else if ((j1 = -k)) {
dval(&u) *= tens[j1 & 0xf];
for(j = j1 >> 4; j; j >>= 1, i++)
if (j & 1) {
ieps++;
dval(&u) *= bigtens[i];
}
}
if (k_check && dval(&u) < 1. && ilim > 0) {
if (ilim1 <= 0)
goto fast_failed;
ilim = ilim1;
k--;
dval(&u) *= 10.;
ieps++;
}
dval(&eps) = ieps*dval(&u) + 7.;
word0(&eps) -= (P-1)*Exp_msk1;
if (ilim == 0) {
S = mhi = 0;
dval(&u) -= 5.;
if (dval(&u) > dval(&eps))
goto one_digit;
if (dval(&u) < -dval(&eps))
goto no_digits;
goto fast_failed;
}
#ifndef No_leftright
if (leftright) {
/* Use Steele & White method of only
* generating digits needed.
*/
dval(&eps) = 0.5/tens[ilim-1] - dval(&eps);
#ifdef IEEE_Arith
if (k0 < 0 && j1 >= 307) {
eps1.d = 1.01e256; /* 1.01 allows roundoff in the next few lines */
word0(&eps1) -= Exp_msk1 * (Bias+P-1);
dval(&eps1) *= tens[j1 & 0xf];
for(i = 0, j = (j1-256) >> 4; j; j >>= 1, i++)
if (j & 1)
dval(&eps1) *= bigtens[i];
if (eps.d < eps1.d)
eps.d = eps1.d;
}
#endif
for(i = 0; {
L = dval(&u);
dval(&u) -= L;
*s++ = '0' + (int)L;
if (1. - dval(&u) < dval(&eps))
goto bump_up;
if (dval(&u) < dval(&eps))
goto ret1;
if (++i >= ilim)
break;
dval(&eps) *= 10.;
dval(&u) *= 10.;
}
}
else {
#endif
/* Generate ilim digits, then fix them up. */
dval(&eps) *= tens[ilim-1];
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u));
if (!(dval(&u) -= L))
ilim = i;
*s++ = '0' + (int)L;
if (i == ilim) {
if (dval(&u) > 0.5 + dval(&eps))
goto bump_up;
else if (dval(&u) < 0.5 - dval(&eps)) {
while(*--s == '0');
s++;
goto ret1;
}
break;
}
}
#ifndef No_leftright
}
#endif
fast_failed:
s = s0;
dval(&u) = dval(&d2);
k = k0;
ilim = ilim0;
}
/* Do we have a "small" integer? */
if (be >= 0 && k <= Int_max) {
/* Yes. */
ds = tens[k];
if (ndigits < 0 && ilim <= 0) {
S = mhi = 0;
if (ilim < 0 || dval(&u) <= 5*ds)
goto no_digits;
goto one_digit;
}
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u) / ds);
dval(&u) -= L*ds;
#ifdef Check_FLT_ROUNDS
/* If FLT_ROUNDS == 2, L will usually be high by 1 */
if (dval(&u) < 0) {
L--;
dval(&u) += ds;
}
#endif
*s++ = '0' + (int)L;
if (!dval(&u)) {
#ifdef SET_INEXACT
inexact = 0;
#endif
break;
}
if (i == ilim) {
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto ret1;
case 2: goto bump_up;
}
#endif
dval(&u) += dval(&u);
#ifdef ROUND_BIASED
if (dval(&u) >= ds)
#else
if (dval(&u) > ds || (dval(&u) == ds && L & 1))
#endif
{
bump_up:
while(*--s == '9')
if (s == s0) {
k++;
*s = '0';
break;
}
++*s++;
}
break;
}
}
goto ret1;
}
m2 = b2;
m5 = b5;
mhi = mlo = 0;
if (leftright) {
i =
#ifndef Sudden_Underflow
denorm ? be + (Bias + (P-1) - 1 + 1) :
#endif
#ifdef IBM
1 + 4*P - 3 - bbits + ((bbits + be - 1) & 3);
#else
1 + P - bbits;
#endif
b2 += i;
s2 += i;
mhi = i2b(1);
}
if (m2 > 0 && s2 > 0) {
i = m2 < s2 ? m2 : s2;
b2 -= i;
m2 -= i;
s2 -= i;
}
if (b5 > 0) {
if (leftright) {
if (m5 > 0) {
mhi = pow5mult(mhi, m5);
b1 = mult(mhi, b);
Bfree(b);
b = b1;
}
if ((j = b5 - m5))
b = pow5mult(b, j);
}
else
b = pow5mult(b, b5);
}
S = i2b(1);
if (s5 > 0)
S = pow5mult(S, s5);
/* Check for special case that d is a normalized power of 2. */
spec_case = 0;
if ((mode < 2 || leftright)
#ifdef Honor_FLT_ROUNDS
&& Rounding == 1
#endif
) {
if (!word1(&u) && !(word0(&u) & Bndry_mask)
#ifndef Sudden_Underflow
&& word0(&u) & (Exp_mask & ~Exp_msk1)
#endif
) {
/* The special case */
b2 += Log2P;
s2 += Log2P;
spec_case = 1;
}
}
/* Arrange for convenient computation of quotients:
* shift left if necessary so divisor has 4 leading 0 bits.
*
* Perhaps we should just compute leading 28 bits of S once
* and for all and pass them and a shift to quorem, so it
* can do shifts and ors to compute the numerator for q.
*/
i = dshift(S, s2);
b2 += i;
m2 += i;
s2 += i;
if (b2 > 0)
b = lshift(b, b2);
if (s2 > 0)
S = lshift(S, s2);
if (k_check) {
if (cmp(b,S) < 0) {
k--;
b = multadd(b, 10, 0); /* we botched the k estimate */
if (leftright)
mhi = multadd(mhi, 10, 0);
ilim = ilim1;
}
}
if (ilim <= 0 && (mode == 3 || mode == 5)) {
if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) {
/* no digits, fcvt style */
no_digits:
k = -1 - ndigits;
goto ret;
}
one_digit:
*s++ = '1';
k++;
goto ret;
}
if (leftright) {
if (m2 > 0)
mhi = lshift(mhi, m2);
/* Compute mlo -- check for special case
* that d is a normalized power of 2.
*/
mlo = mhi;
if (spec_case) {
mhi = Balloc(mhi->k);
Bcopy(mhi, mlo);
mhi = lshift(mhi, Log2P);
}
for(i = 1;;i++) {
dig = quorem(b,S) + '0';
/* Do we yet have the shortest decimal string
* that will round to d?
*/
j = cmp(b, mlo);
delta = diff(S, mhi);
j1 = delta->sign ? 1 : cmp(b, delta);
Bfree(delta);
#ifndef ROUND_BIASED
if (j1 == 0 && mode != 1 && !(word1(&u) & 1)
#ifdef Honor_FLT_ROUNDS
&& Rounding >= 1
#endif
) {
if (dig == '9')
goto round_9_up;
if (j > 0)
dig++;
#ifdef SET_INEXACT
else if (!b->x[0] && b->wds <= 1)
inexact = 0;
#endif
*s++ = dig;
goto ret;
}
#endif
if (j < 0 || (j == 0 && mode != 1
#ifndef ROUND_BIASED
&& !(word1(&u) & 1)
#endif
)) {
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto accept_dig;
}
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto accept_dig;
case 2: goto keep_dig;
}
#endif /*Honor_FLT_ROUNDS*/
if (j1 > 0) {
b = lshift(b, 1);
j1 = cmp(b, S);
#ifdef ROUND_BIASED
if (j1 >= 0 /*)*/
#else
if ((j1 > 0 || (j1 == 0 && dig & 1))
#endif
&& dig++ == '9')
goto round_9_up;
}
accept_dig:
*s++ = dig;
goto ret;
}
if (j1 > 0) {
#ifdef Honor_FLT_ROUNDS
if (!Rounding)
goto accept_dig;
#endif
if (dig == '9') { /* possible if i == 1 */
round_9_up:
*s++ = '9';
goto roundoff;
}
*s++ = dig + 1;
goto ret;
}
#ifdef Honor_FLT_ROUNDS
keep_dig:
#endif
*s++ = dig;
if (i == ilim)
break;
b = multadd(b, 10, 0);
if (mlo == mhi)
mlo = mhi = multadd(mhi, 10, 0);
else {
mlo = multadd(mlo, 10, 0);
mhi = multadd(mhi, 10, 0);
}
}
}
else
for(i = 1;; i++) {
*s++ = dig = quorem(b,S) + '0';
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto ret;
}
if (i >= ilim)
break;
b = multadd(b, 10, 0);
}
/* Round off last digit */
#ifdef Honor_FLT_ROUNDS
switch(Rounding) {
case 0: goto trimzeros;
case 2: goto roundoff;
}
#endif
b = lshift(b, 1);
j = cmp(b, S);
#ifdef ROUND_BIASED
if (j >= 0)
#else
if (j > 0 || (j == 0 && dig & 1))
#endif
{
roundoff:
while(*--s == '9')
if (s == s0) {
k++;
*s++ = '1';
goto ret;
}
++*s++;
}
else {
#ifdef Honor_FLT_ROUNDS
trimzeros:
#endif
while(*--s == '0');
s++;
}
ret:
Bfree(S);
if (mhi) {
if (mlo && mlo != mhi)
Bfree(mlo);
Bfree(mhi);
}
ret1:
#ifdef SET_INEXACT
if (inexact) {
if (!oldinexact) {
word0(&u) = Exp_1 + (70 << Exp_shift);
word1(&u) = 0;
dval(&u) += 1.;
}
}
else if (!oldinexact)
clear_inexact();
#endif
Bfree(b);
*s = 0;
*decpt = k + 1;
if (rve)
*rve = s;
return s0;
}
#ifdef __cplusplus
}
#endif
The thing is variable s is actually a char* so a string... This code is such a mess to read through.
Well, it was written when disk space actually still mattered. Saving 500 bytes on variable names made all the difference.
That said, someone should really at least fix the variable names to something easier to understand and add a few braces where they've been omitted.
The gotos are probably there to stay since C that close to the system often has those for performance reasons. I'd expect a modern compiler to optimize better without them, but Linux system and kernel programmers, do love their gotos since back in the day you could save a few processor cycles with them.
All in all, it's another example for why I don't engage in open source projects. All the projects I checked out have too many programmers with too little real world experience that write "clever" instead of good code, legacy code that the project creator wrote half-drunk 10 years ago that no one dares to touch for fear of breaking everything and too many people that have a hard-on for micro-optimizations while writing slow algorithms.
|
On April 27 2016 06:07 Manit0u wrote:Lemme put this in perspective: + Show Spoiler +
char *
dtoa
#ifdef KR_headers
(dd, mode, ndigits, decpt, sign, rve)
double dd; int mode, ndigits, *decpt, *sign; char **rve;
#else
(double dd, int mode, int ndigits, int *decpt, int *sign, char **rve)
#endif
{
/* Arguments ndigits, decpt, sign are similar to those
of ecvt and fcvt; trailing zeros are suppressed from
the returned string. If not null, *rve is set to point
to the end of the return value. If d is +-Infinity or NaN,
then *decpt is set to 9999.
mode:
0 ==> shortest string that yields d when read in
and rounded to nearest.
1 ==> like 0, but with Steele & White stopping rule;
e.g. with IEEE P754 arithmetic , mode 0 gives
1e23 whereas mode 1 gives 9.999999999999999e22.
2 ==> max(1,ndigits) significant digits. This gives a
return value similar to that of ecvt, except
that trailing zeros are suppressed.
3 ==> through ndigits past the decimal point. This
gives a return value similar to that from fcvt,
except that trailing zeros are suppressed, and
ndigits can be negative.
4,5 ==> similar to 2 and 3, respectively, but (in
round-nearest mode) with the tests of mode 0 to
possibly return a shorter string that rounds to d.
With IEEE arithmetic and compilation with
-DHonor_FLT_ROUNDS, modes 4 and 5 behave the same
as modes 2 and 3 when FLT_ROUNDS != 1.
6-9 ==> Debugging modes similar to mode - 4: don't try
fast floating-point estimate (if applicable).
Values of mode other than 0-9 are treated as mode 0.
Sufficient space is allocated to the return value
to hold the suppressed trailing zeros.
*/
int bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1,
j, j1, k, k0, k_check, leftright, m2, m5, s2, s5,
spec_case, try_quick;
Long L;
#ifndef Sudden_Underflow
int denorm;
ULong x;
#endif
Bigint *b, *b1, *delta, *mlo, *mhi, *S;
U d2, eps, u;
double ds;
char *s, *s0;
#ifndef No_leftright
#ifdef IEEE_Arith
U eps1;
#endif
#endif
#ifdef SET_INEXACT
int inexact, oldinexact;
#endif
#ifdef Honor_FLT_ROUNDS /*{*/
int Rounding;
#ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
Rounding = Flt_Rounds;
#else /*}{*/
Rounding = 1;
switch(fegetround()) {
case FE_TOWARDZERO: Rounding = 0; break;
case FE_UPWARD: Rounding = 2; break;
case FE_DOWNWARD: Rounding = 3;
}
#endif /*}}*/
#endif /*}*/
#ifndef MULTIPLE_THREADS
if (dtoa_result) {
freedtoa(dtoa_result);
dtoa_result = 0;
}
#endif
u.d = dd;
if (word0(&u) & Sign_bit) {
/* set sign for everything, including 0's and NaNs */
*sign = 1;
word0(&u) &= ~Sign_bit; /* clear sign bit */
}
else
*sign = 0;
#if defined(IEEE_Arith) + defined(VAX)
#ifdef IEEE_Arith
if ((word0(&u) & Exp_mask) == Exp_mask)
#else
if (word0(&u) == 0x8000)
#endif
{
/* Infinity or NaN */
*decpt = 9999;
#ifdef IEEE_Arith
if (!word1(&u) && !(word0(&u) & 0xfffff))
return nrv_alloc("Infinity", rve, 8);
#endif
return nrv_alloc("NaN", rve, 3);
}
#endif
#ifdef IBM
dval(&u) += 0; /* normalize */
#endif
if (!dval(&u)) {
*decpt = 1;
return nrv_alloc("0", rve, 1);
}
#ifdef SET_INEXACT
try_quick = oldinexact = get_inexact();
inexact = 1;
#endif
#ifdef Honor_FLT_ROUNDS
if (Rounding >= 2) {
if (*sign)
Rounding = Rounding == 2 ? 0 : 2;
else
if (Rounding != 2)
Rounding = 0;
}
#endif
b = d2b(&u, &be, &bbits);
#ifdef Sudden_Underflow
i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
#else
if ((i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
#endif
dval(&d2) = dval(&u);
word0(&d2) &= Frac_mask1;
word0(&d2) |= Exp_11;
#ifdef IBM
if (j = 11 - hi0bits(word0(&d2) & Frac_mask))
dval(&d2) /= 1 << j;
#endif
/* log(x) ~=~ log(1.5) + (x-1.5)/1.5
* log10(x) = log(x) / log(10)
* ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
* log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
*
* This suggests computing an approximation k to log10(d) by
*
* k = (i - Bias)*0.301029995663981
* + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
*
* We want k to be too large rather than too small.
* The error in the first-order Taylor series approximation
* is in our favor, so we just round up the constant enough
* to compensate for any error in the multiplication of
* (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
* and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
* adding 1e-13 to the constant term more than suffices.
* Hence we adjust the constant term to 0.1760912590558.
* (We could get a more accurate k by invoking log10,
* but this is probably not worthwhile.)
*/
i -= Bias;
#ifdef IBM
i <<= 2;
i += j;
#endif
#ifndef Sudden_Underflow
denorm = 0;
}
else {
/* d is denormalized */
i = bbits + be + (Bias + (P-1) - 1);
x = i > 32 ? word0(&u) << (64 - i) | word1(&u) >> (i - 32)
: word1(&u) << (32 - i);
dval(&d2) = x;
word0(&d2) -= 31*Exp_msk1; /* adjust exponent */
i -= (Bias + (P-1) - 1) + 1;
denorm = 1;
}
#endif
ds = (dval(&d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
k = (int)ds;
if (ds < 0. && ds != k)
k--; /* want k = floor(ds) */
k_check = 1;
if (k >= 0 && k <= Ten_pmax) {
if (dval(&u) < tens[k]
k--;
k_check = 0;
}
j = bbits - i - 1;
if (j >= 0) {
b2 = 0;
s2 = j;
}
else {
b2 = -j;
s2 = 0;
}
if (k >= 0) {
b5 = 0;
s5 = k;
s2 += k;
}
else {
b2 -= k;
b5 = -k;
s5 = 0;
}
if (mode < 0 || mode > 9)
mode = 0;
#ifndef SET_INEXACT
#ifdef Check_FLT_ROUNDS
try_quick = Rounding == 1;
#else
try_quick = 1;
#endif
#endif /*SET_INEXACT*/
if (mode > 5) {
mode -= 4;
try_quick = 0;
}
leftright = 1;
ilim = ilim1 = -1; /* Values for cases 0 and 1; done here to */
/* silence erroneous "gcc -Wall" warning. */
switch(mode) {
case 0:
case 1:
i = 18;
ndigits = 0;
break;
case 2:
leftright = 0;
/* no break */
case 4:
if (ndigits <= 0)
ndigits = 1;
ilim = ilim1 = i = ndigits;
break;
case 3:
leftright = 0;
/* no break */
case 5:
i = ndigits + k + 1;
ilim = i;
ilim1 = i - 1;
if (i <= 0)
i = 1;
}
s = s0 = rv_alloc(i);
#ifdef Honor_FLT_ROUNDS
if (mode > 1 && Rounding != 1)
leftright = 0;
#endif
if (ilim >= 0 && ilim <= Quick_max && try_quick) {
/* Try to get by with floating-point arithmetic. */
i = 0;
dval(&d2) = dval(&u);
k0 = k;
ilim0 = ilim;
ieps = 2; /* conservative */
if (k > 0) {
ds = tens[k&0xf];
j = k >> 4;
if (j & Bletch) {
/* prevent overflows */
j &= Bletch - 1;
dval(&u) /= bigtens[n_bigtens-1];
ieps++;
}
for(; j; j >>= 1, i++)
if (j & 1) {
ieps++;
ds *= bigtens[i];
}
dval(&u) /= ds;
}
else if ((j1 = -k)) {
dval(&u) *= tens[j1 & 0xf];
for(j = j1 >> 4; j; j >>= 1, i++)
if (j & 1) {
ieps++;
dval(&u) *= bigtens[i];
}
}
if (k_check && dval(&u) < 1. && ilim > 0) {
if (ilim1 <= 0)
goto fast_failed;
ilim = ilim1;
k--;
dval(&u) *= 10.;
ieps++;
}
dval(&eps) = ieps*dval(&u) + 7.;
word0(&eps) -= (P-1)*Exp_msk1;
if (ilim == 0) {
S = mhi = 0;
dval(&u) -= 5.;
if (dval(&u) > dval(&eps))
goto one_digit;
if (dval(&u) < -dval(&eps))
goto no_digits;
goto fast_failed;
}
#ifndef No_leftright
if (leftright) {
/* Use Steele & White method of only
* generating digits needed.
*/
dval(&eps) = 0.5/tens[ilim-1] - dval(&eps);
#ifdef IEEE_Arith
if (k0 < 0 && j1 >= 307) {
eps1.d = 1.01e256; /* 1.01 allows roundoff in the next few lines */
word0(&eps1) -= Exp_msk1 * (Bias+P-1);
dval(&eps1) *= tens[j1 & 0xf];
for(i = 0, j = (j1-256) >> 4; j; j >>= 1, i++)
if (j & 1)
dval(&eps1) *= bigtens[i];
if (eps.d < eps1.d)
eps.d = eps1.d;
}
#endif
for(i = 0; {
L = dval(&u);
dval(&u) -= L;
*s++ = '0' + (int)L;
if (1. - dval(&u) < dval(&eps))
goto bump_up;
if (dval(&u) < dval(&eps))
goto ret1;
if (++i >= ilim)
break;
dval(&eps) *= 10.;
dval(&u) *= 10.;
}
}
else {
#endif
/* Generate ilim digits, then fix them up. */
dval(&eps) *= tens[ilim-1];
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u));
if (!(dval(&u) -= L))
ilim = i;
*s++ = '0' + (int)L;
if (i == ilim) {
if (dval(&u) > 0.5 + dval(&eps))
goto bump_up;
else if (dval(&u) < 0.5 - dval(&eps)) {
while(*--s == '0');
s++;
goto ret1;
}
break;
}
}
#ifndef No_leftright
}
#endif
fast_failed:
s = s0;
dval(&u) = dval(&d2);
k = k0;
ilim = ilim0;
}
/* Do we have a "small" integer? */
if (be >= 0 && k <= Int_max) {
/* Yes. */
ds = tens[k];
if (ndigits < 0 && ilim <= 0) {
S = mhi = 0;
if (ilim < 0 || dval(&u) <= 5*ds)
goto no_digits;
goto one_digit;
}
for(i = 1;; i++, dval(&u) *= 10.) {
L = (Long)(dval(&u) / ds);
dval(&u) -= L*ds;
#ifdef Check_FLT_ROUNDS
/* If FLT_ROUNDS == 2, L will usually be high by 1 */
if (dval(&u) < 0) {
L--;
dval(&u) += ds;
}
#endif
*s++ = '0' + (int)L;
if (!dval(&u)) {
#ifdef SET_INEXACT
inexact = 0;
#endif
break;
}
if (i == ilim) {
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto ret1;
case 2: goto bump_up;
}
#endif
dval(&u) += dval(&u);
#ifdef ROUND_BIASED
if (dval(&u) >= ds)
#else
if (dval(&u) > ds || (dval(&u) == ds && L & 1))
#endif
{
bump_up:
while(*--s == '9')
if (s == s0) {
k++;
*s = '0';
break;
}
++*s++;
}
break;
}
}
goto ret1;
}
m2 = b2;
m5 = b5;
mhi = mlo = 0;
if (leftright) {
i =
#ifndef Sudden_Underflow
denorm ? be + (Bias + (P-1) - 1 + 1) :
#endif
#ifdef IBM
1 + 4*P - 3 - bbits + ((bbits + be - 1) & 3);
#else
1 + P - bbits;
#endif
b2 += i;
s2 += i;
mhi = i2b(1);
}
if (m2 > 0 && s2 > 0) {
i = m2 < s2 ? m2 : s2;
b2 -= i;
m2 -= i;
s2 -= i;
}
if (b5 > 0) {
if (leftright) {
if (m5 > 0) {
mhi = pow5mult(mhi, m5);
b1 = mult(mhi, b);
Bfree(b);
b = b1;
}
if ((j = b5 - m5))
b = pow5mult(b, j);
}
else
b = pow5mult(b, b5);
}
S = i2b(1);
if (s5 > 0)
S = pow5mult(S, s5);
/* Check for special case that d is a normalized power of 2. */
spec_case = 0;
if ((mode < 2 || leftright)
#ifdef Honor_FLT_ROUNDS
&& Rounding == 1
#endif
) {
if (!word1(&u) && !(word0(&u) & Bndry_mask)
#ifndef Sudden_Underflow
&& word0(&u) & (Exp_mask & ~Exp_msk1)
#endif
) {
/* The special case */
b2 += Log2P;
s2 += Log2P;
spec_case = 1;
}
}
/* Arrange for convenient computation of quotients:
* shift left if necessary so divisor has 4 leading 0 bits.
*
* Perhaps we should just compute leading 28 bits of S once
* and for all and pass them and a shift to quorem, so it
* can do shifts and ors to compute the numerator for q.
*/
i = dshift(S, s2);
b2 += i;
m2 += i;
s2 += i;
if (b2 > 0)
b = lshift(b, b2);
if (s2 > 0)
S = lshift(S, s2);
if (k_check) {
if (cmp(b,S) < 0) {
k--;
b = multadd(b, 10, 0); /* we botched the k estimate */
if (leftright)
mhi = multadd(mhi, 10, 0);
ilim = ilim1;
}
}
if (ilim <= 0 && (mode == 3 || mode == 5)) {
if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) {
/* no digits, fcvt style */
no_digits:
k = -1 - ndigits;
goto ret;
}
one_digit:
*s++ = '1';
k++;
goto ret;
}
if (leftright) {
if (m2 > 0)
mhi = lshift(mhi, m2);
/* Compute mlo -- check for special case
* that d is a normalized power of 2.
*/
mlo = mhi;
if (spec_case) {
mhi = Balloc(mhi->k);
Bcopy(mhi, mlo);
mhi = lshift(mhi, Log2P);
}
for(i = 1;;i++) {
dig = quorem(b,S) + '0';
/* Do we yet have the shortest decimal string
* that will round to d?
*/
j = cmp(b, mlo);
delta = diff(S, mhi);
j1 = delta->sign ? 1 : cmp(b, delta);
Bfree(delta);
#ifndef ROUND_BIASED
if (j1 == 0 && mode != 1 && !(word1(&u) & 1)
#ifdef Honor_FLT_ROUNDS
&& Rounding >= 1
#endif
) {
if (dig == '9')
goto round_9_up;
if (j > 0)
dig++;
#ifdef SET_INEXACT
else if (!b->x[0] && b->wds <= 1)
inexact = 0;
#endif
*s++ = dig;
goto ret;
}
#endif
if (j < 0 || (j == 0 && mode != 1
#ifndef ROUND_BIASED
&& !(word1(&u) & 1)
#endif
)) {
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto accept_dig;
}
#ifdef Honor_FLT_ROUNDS
if (mode > 1)
switch(Rounding) {
case 0: goto accept_dig;
case 2: goto keep_dig;
}
#endif /*Honor_FLT_ROUNDS*/
if (j1 > 0) {
b = lshift(b, 1);
j1 = cmp(b, S);
#ifdef ROUND_BIASED
if (j1 >= 0 /*)*/
#else
if ((j1 > 0 || (j1 == 0 && dig & 1))
#endif
&& dig++ == '9')
goto round_9_up;
}
accept_dig:
*s++ = dig;
goto ret;
}
if (j1 > 0) {
#ifdef Honor_FLT_ROUNDS
if (!Rounding)
goto accept_dig;
#endif
if (dig == '9') { /* possible if i == 1 */
round_9_up:
*s++ = '9';
goto roundoff;
}
*s++ = dig + 1;
goto ret;
}
#ifdef Honor_FLT_ROUNDS
keep_dig:
#endif
*s++ = dig;
if (i == ilim)
break;
b = multadd(b, 10, 0);
if (mlo == mhi)
mlo = mhi = multadd(mhi, 10, 0);
else {
mlo = multadd(mlo, 10, 0);
mhi = multadd(mhi, 10, 0);
}
}
}
else
for(i = 1;; i++) {
*s++ = dig = quorem(b,S) + '0';
if (!b->x[0] && b->wds <= 1) {
#ifdef SET_INEXACT
inexact = 0;
#endif
goto ret;
}
if (i >= ilim)
break;
b = multadd(b, 10, 0);
}
/* Round off last digit */
#ifdef Honor_FLT_ROUNDS
switch(Rounding) {
case 0: goto trimzeros;
case 2: goto roundoff;
}
#endif
b = lshift(b, 1);
j = cmp(b, S);
#ifdef ROUND_BIASED
if (j >= 0)
#else
if (j > 0 || (j == 0 && dig & 1))
#endif
{
roundoff:
while(*--s == '9')
if (s == s0) {
k++;
*s++ = '1';
goto ret;
}
++*s++;
}
else {
#ifdef Honor_FLT_ROUNDS
trimzeros:
#endif
while(*--s == '0');
s++;
}
ret:
Bfree(S);
if (mhi) {
if (mlo && mlo != mhi)
Bfree(mlo);
Bfree(mhi);
}
ret1:
#ifdef SET_INEXACT
if (inexact) {
if (!oldinexact) {
word0(&u) = Exp_1 + (70 << Exp_shift);
word1(&u) = 0;
dval(&u) += 1.;
}
}
else if (!oldinexact)
clear_inexact();
#endif
Bfree(b);
*s = 0;
*decpt = k + 1;
if (rve)
*rve = s;
return s0;
}
#ifdef __cplusplus
}
#endif
The thing is variable s is actually a char* so a string... This code is such a mess to read through.
Suddenly, this does not look so bad eh
On April 05 2016 04:44 Manit0u wrote:+ Show Spoiler +![[image loading]](http://asset-8.soupcdn.com/asset/16066/4710_8841.png) So... I heard you like callbacks...
|
On April 27 2016 10:43 WarSame wrote:Folks, looking for a bit of help with mean.io. I dled and installed node, mongodb and git. I then init a directory and run npm install inside of it. I then run gulp to start the server. This throws errors that I'm missing various modules such as 'mongoose', 'async', etc. but these should be installed from the npm install, correct? The exact error is + Show Spoiler +E:\mean_workspace\monoprobability\node_modules\q\q.js:155
throw e;
^
Error: Cannot find module 'mongoose'
at Function.Module._resolveFilename (module.js:325:15)
at Function.Module._load (module.js:276:25)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\server\models\user.js:6:17)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at requireModel (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:116:19)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:21:7
at Array.forEach (native)
at walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:23:7
at Array.forEach (native)
at Object.walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at MeanUserKlass.Module (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:134:14)
at new MeanUserKlass (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:10:10)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:21:16)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Module.activate (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\dependablelist.js:52:15)
When I tried to start using mean.io on another computer it worked fine so it is almost certainly a problem with my current environment. When I look inside of my root's node_modules folder it is missing both 'async' and 'mongoose'. Are they supposed to be in that folder?
Can't you copy them from the other computer and see if that solves the issue for you?
|
On April 27 2016 10:43 WarSame wrote:Folks, looking for a bit of help with mean.io. I dled and installed node, mongodb and git. I then init a directory and run npm install inside of it. I then run gulp to start the server. This throws errors that I'm missing various modules such as 'mongoose', 'async', etc. but these should be installed from the npm install, correct? The exact error is + Show Spoiler +E:\mean_workspace\monoprobability\node_modules\q\q.js:155
throw e;
^
Error: Cannot find module 'mongoose'
at Function.Module._resolveFilename (module.js:325:15)
at Function.Module._load (module.js:276:25)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\server\models\user.js:6:17)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at requireModel (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:116:19)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:21:7
at Array.forEach (native)
at walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:23:7
at Array.forEach (native)
at Object.walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at MeanUserKlass.Module (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:134:14)
at new MeanUserKlass (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:10:10)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:21:16)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Module.activate (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\dependablelist.js:52:15)
When I tried to start using mean.io on another computer it worked fine so it is almost certainly a problem with my current environment. When I look inside of my root's node_modules folder it is missing both 'async' and 'mongoose'. Are they supposed to be in that folder?
Is your internet stable, and no timeout problems? I've had issues with npm skipping stuff if it cannot get it sufficiently quickly, and then claiming success all the same. rerunning npm install usually works, but sometimes it's really confused and you need to throw away your node_modules and start again. either that, or your package.json is wrong.
|
|
|
On April 27 2016 23:13 Hadronsbecrazy wrote:
Is C# still widely used?
In the Windows world, yes.
Also, Unity is using C# for it's scripting, so pretty much all the Unity based games use it.
|
On April 27 2016 18:41 Wrath wrote:Show nested quote +On April 27 2016 10:43 WarSame wrote:Folks, looking for a bit of help with mean.io. I dled and installed node, mongodb and git. I then init a directory and run npm install inside of it. I then run gulp to start the server. This throws errors that I'm missing various modules such as 'mongoose', 'async', etc. but these should be installed from the npm install, correct? The exact error is + Show Spoiler +E:\mean_workspace\monoprobability\node_modules\q\q.js:155
throw e;
^
Error: Cannot find module 'mongoose'
at Function.Module._resolveFilename (module.js:325:15)
at Function.Module._load (module.js:276:25)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\server\models\user.js:6:17)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at requireModel (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:116:19)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:21:7
at Array.forEach (native)
at walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:23:7
at Array.forEach (native)
at Object.walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at MeanUserKlass.Module (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:134:14)
at new MeanUserKlass (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:10:10)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:21:16)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Module.activate (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\dependablelist.js:52:15)
When I tried to start using mean.io on another computer it worked fine so it is almost certainly a problem with my current environment. When I look inside of my root's node_modules folder it is missing both 'async' and 'mongoose'. Are they supposed to be in that folder? Can't you copy them from the other computer and see if that solves the issue for you?
The other computer is a work computer which disables copying files :/
On April 27 2016 19:43 Acrofales wrote:Show nested quote +On April 27 2016 10:43 WarSame wrote:Folks, looking for a bit of help with mean.io. I dled and installed node, mongodb and git. I then init a directory and run npm install inside of it. I then run gulp to start the server. This throws errors that I'm missing various modules such as 'mongoose', 'async', etc. but these should be installed from the npm install, correct? The exact error is + Show Spoiler +E:\mean_workspace\monoprobability\node_modules\q\q.js:155
throw e;
^
Error: Cannot find module 'mongoose'
at Function.Module._resolveFilename (module.js:325:15)
at Function.Module._load (module.js:276:25)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\server\models\user.js:6:17)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at requireModel (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:116:19)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:21:7
at Array.forEach (native)
at walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:23:7
at Array.forEach (native)
at Object.walk (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\util.js:16:25)
at MeanUserKlass.Module (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\index.js:134:14)
at new MeanUserKlass (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:10:10)
at Object.<anonymous> (E:\mean_workspace\monoprobability\node_modules\meanio-users\app.js:21:16)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Module.require (module.js:353:17)
at require (internal/module.js:12:17)
at Module.activate (E:\mean_workspace\monoprobability\node_modules\meanio\lib\core_modules\module\dependablelist.js:52:15)
When I tried to start using mean.io on another computer it worked fine so it is almost certainly a problem with my current environment. When I look inside of my root's node_modules folder it is missing both 'async' and 'mongoose'. Are they supposed to be in that folder? Is your internet stable, and no timeout problems? I've had issues with npm skipping stuff if it cannot get it sufficiently quickly, and then claiming success all the same. rerunning npm install usually works, but sometimes it's really confused and you need to throw away your node_modules and start again. either that, or your package.json is wrong.
Yup, my internet is pretty stable here. I've run the command like 5 times in a row and I've deleted and reinited the app ~5 times too, so that shouldn't be it. My package.json is simply the default mean.io package, so it should be fine.
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Wow, I'm an idiot!
I just spent two hours trying to figure out why the Live USB I was making wouldn't boot, when I was making a typo when writing the image.
I was doing:
sudo dd if=Fedora-Live-Workstation-x86_64-23-10.iso of=/dev/sdc1 bs=8M; and sync
Instead of:
sudo dd if=Fedora-Live-Workstation-x86_64-23-10.iso of=/dev/sdc bs=8M; and sync
Whoops! 
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On April 27 2016 16:49 Morfildur wrote:
Well, it was written when disk space actually still mattered. Saving 500 bytes on variable names made all the difference.
That said, someone should really at least fix the variable names to something easier to understand and add a few braces where they've been omitted.
Strongly disagree... don't touch code that works  Among the worst sins you can commit as a programmer is breaking things for the sake of pretty code.
On April 27 2016 16:49 Morfildur wrote:
The gotos are probably there to stay since C that close to the system often has those for performance reasons. I'd expect a modern compiler to optimize better without them, but Linux system and kernel programmers, do love their gotos since back in the day you could save a few processor cycles with them.
All in all, it's another example for why I don't engage in open source projects. All the projects I checked out have too many programmers with too little real world experience that write "clever" instead of good code, legacy code that the project creator wrote half-drunk 10 years ago that no one dares to touch for fear of breaking everything and too many people that have a hard-on for micro-optimizations while writing slow algorithms.
Also somewhat disagree that the gotos are for performance reasons. They're significantly more readable than the alternative. Using gotos properly in C can save you a ton of duplicated cleanup code, which is why those C programmers (Linux devs, GCC devs, BSD devs...) like them so much.
eg:
int func() {
int err;
struct foo *a = alloc_foo();
if (!a) return;
err = init_foo(a);
if (err) {
free_foo(a);
return err;
}
err = do_something_with_foo(a);
if (err) {
free_foo(a);
return err;
}
return 0;
}
vs.
int func() {
int err;
struct foo *a = alloc_foo();
if (!a) goto fail;
err = init_foo(a);
if (err) goto fail;
err = do_something_with_foo(a);
if (err) goto fail;
return 0;
fail:
free_foo(a);
return err;
}
I mean, maybe a pretty trivial example, but there are places in the Linux kernel where this style of error handling reduces code duplication by a really significant amount.
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On April 28 2016 04:33 Cyx. wrote:Show nested quote +On April 27 2016 16:49 Morfildur wrote:
Well, it was written when disk space actually still mattered. Saving 500 bytes on variable names made all the difference.
That said, someone should really at least fix the variable names to something easier to understand and add a few braces where they've been omitted.
Strongly disagree... don't touch code that works Among the worst sins you can commit as a programmer is breaking things for the sake of pretty code. Show nested quote +On April 27 2016 16:49 Morfildur wrote:
The gotos are probably there to stay since C that close to the system often has those for performance reasons. I'd expect a modern compiler to optimize better without them, but Linux system and kernel programmers, do love their gotos since back in the day you could save a few processor cycles with them.
All in all, it's another example for why I don't engage in open source projects. All the projects I checked out have too many programmers with too little real world experience that write "clever" instead of good code, legacy code that the project creator wrote half-drunk 10 years ago that no one dares to touch for fear of breaking everything and too many people that have a hard-on for micro-optimizations while writing slow algorithms.
Also somewhat disagree that the gotos are for performance reasons. They're significantly more readable than the alternative. Using gotos properly in C can save you a ton of duplicated cleanup code, which is why those C programmers (Linux devs, GCC devs, BSD devs...) like them so much. eg:
int func() {
int err;
struct foo *a = alloc_foo();
if (!a) return;
err = init_foo(a);
if (err) {
free_foo(a);
return err;
}
err = do_something_with_foo(a);
if (err) {
free_foo(a);
return err;
}
return 0;
}
vs.
int func() {
int err;
struct foo *a = alloc_foo();
if (!a) goto fail;
err = init_foo(a);
if (err) goto fail;
err = do_something_with_foo(a);
if (err) goto fail;
return 0;
fail:
free_foo(a);
return err;
}
I mean, maybe a pretty trivial example, but there are places in the Linux kernel where this style of error handling reduces code duplication by a really significant amount.
Can do that just fine without gotos.
int func() {
int err;
struct foo *a = alloc_foo();
if (!a) return fail(a, err);
err = init_foo(a);
if (err) return fail(a, err);
err = do_something_with_foo(a);
if (err) return fail(a, err);
return 0;
}
int fail(foo *a, int err) {
free_foo(a);
return err;
}
And the advantage of this is that your code will never ever enter the fail code by mistake because you forgot a corner case in which there is no return statement above your label.
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[..]
int err;
[..]
brrrrrr......
int err;
struct foo *a = alloc_foo();
if (!a) return fail(a, err);
What will this return? Same question for the goto implementation.
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On April 28 2016 05:22 Khalum wrote:
[..]
int err;
[..]
brrrrrr......
It's not that bad if you need more than just true/false. C doesn't have exceptions, so you have to work with what you have, and error as return value is a pretty common approach (probably the most common, in fact).
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EPT
