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On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks.
That's why I don't have any faith in people that became programmers in university.
Too many people get through it without being able to actually program properly. We currently have two students working as programmers in our company, and one of them is meh, the other would write pretty much the same code as your student and wonder why it doesn't work. Sometimes it takes more work to clean up their mess of 300 line methods and huge classes than to actually write it from scratch myself.
One one hand it's of course a recruiting fail to even employ such a student, on the other you'd expect someone studying to become a programmer to at least know the basics of programming.
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On April 18 2016 16:53 Morfildur wrote:Show nested quote +On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks. That's why I don't have any faith in people that became programmers in university. Too many people get through it without being able to actually program properly. We currently have two students working as programmers in our company, and one of them is meh, the other would write pretty much the same code as your student and wonder why it doesn't work. Sometimes it takes more work to clean up their mess of 300 line methods and huge classes than to actually write it from scratch myself. One one hand it's of course a recruiting fail to even employ such a student, on the other you'd expect someone studying to become a programmer to at least know the basics of programming.
I learnt programming while I was at university, but university sure didn't help a lot with that. The basic math courses are fine (because you learn logic and proof concepts). But the CompSci courses... I can't remember anything worthwhile from those.
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On April 19 2016 02:12 spinesheath wrote:Show nested quote +On April 18 2016 16:53 Morfildur wrote:On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks. That's why I don't have any faith in people that became programmers in university. Too many people get through it without being able to actually program properly. We currently have two students working as programmers in our company, and one of them is meh, the other would write pretty much the same code as your student and wonder why it doesn't work. Sometimes it takes more work to clean up their mess of 300 line methods and huge classes than to actually write it from scratch myself. One one hand it's of course a recruiting fail to even employ such a student, on the other you'd expect someone studying to become a programmer to at least know the basics of programming. I learnt programming while I was at university, but university sure didn't help a lot with that. The basic math courses are fine (because you learn logic and proof concepts). But the CompSci courses... I can't remember anything worthwhile from those.
Algorithms and Data Structures are fairly useful. Other than that, maybe the course on OOMP and Design Patterns was decent. I guess the course on functional programming was probably useful, because it really hammered in how to use recursion (although learning how to build your own parser, and compiler, taught that lesson quite thoroughly too). But most of the CS 101 are things I either knew already (programming) or you look up when you need it (courses on network architectures, databases).
I tend to agree that a university (BSc) degree says very little other than that the prospective employee passes a minimum level of intelligence and persistency. I can attest to the fact that you don't actually need to program at all to get a BSc. with a major in CS. I helped plenty of people in group assignments (who had already passed all the 101 programming courses) who couldn't code to save their lives. On the other hand, I am perfectly happy to admit that some of my friends were infinitely better coders than I was, easily navigating complex C libraries to deal with distributing our code across dozens of cores in a supercomputer (probably one of the hardest programming assignments I did in uni... ironically, it was a math course, and not a CS one).
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On April 19 2016 02:49 Acrofales wrote:Show nested quote +On April 19 2016 02:12 spinesheath wrote:On April 18 2016 16:53 Morfildur wrote:On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks. That's why I don't have any faith in people that became programmers in university. Too many people get through it without being able to actually program properly. We currently have two students working as programmers in our company, and one of them is meh, the other would write pretty much the same code as your student and wonder why it doesn't work. Sometimes it takes more work to clean up their mess of 300 line methods and huge classes than to actually write it from scratch myself. One one hand it's of course a recruiting fail to even employ such a student, on the other you'd expect someone studying to become a programmer to at least know the basics of programming. I learnt programming while I was at university, but university sure didn't help a lot with that. The basic math courses are fine (because you learn logic and proof concepts). But the CompSci courses... I can't remember anything worthwhile from those. Algorithms and Data Structures are fairly useful. Other than that, maybe the course on OOMP and Design Patterns was decent. I guess the course on functional programming was probably useful, because it really hammered in how to use recursion (although learning how to build your own parser, and compiler, taught that lesson quite thoroughly too). But most of the CS 101 are things I either knew already (programming) or you look up when you need it (courses on network architectures, databases). I tend to agree that a university (BSc) degree says very little other than that the prospective employee passes a minimum level of intelligence and persistency. I can attest to the fact that you don't actually need to program at all to get a BSc. with a major in CS. I helped plenty of people in group assignments (who had already passed all the 101 programming courses) who couldn't code to save their lives. On the other hand, I am perfectly happy to admit that some of my friends were infinitely better coders than I was, easily navigating complex C libraries to deal with distributing our code across dozens of cores in a supercomputer (probably one of the hardest programming assignments I did in uni... ironically, it was a math course, and not a CS one).
Math be hard man. Programming is something you don't have to learn at the uni (I have bachelor's in sociology for example and did 3 years of history + philosophy beforehand). All I can tell you is that philosophy is actually really good course for programming as it should teach you to think in abstracts (I guess that people who fail at that will also fail at programming). Logic is useful too.
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On April 16 2016 18:44 Ropid wrote:What I wonder is, are you sure you don't want just this here: > echo "%USERPROFILE%\AppData\Roaming\SketchUp\SketchUp 2016\SketchUp\Classifications"
"C:\users\lilwisper\AppData\Roaming\SketchUp\SketchUp 2016\SketchUp\Classifications"
This worked once I took the extra \ out at the end of my script. Thanks for the idea!
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Our university never really taught us "how" to program, just concepts and the best practices kind of stuff was left untouched unless it came up randomly. I'd love it if someone went through and reviewed code for you and told you why it's bad to do X, but you kinda just have to learn that for yourself through reading or fucking up tremendously to where your program won't work.
To my next point though... I'm working on a project which needs to store objects (bitmap images) in a list. This list gets shuffled and I need to know when this list is back in order again after various swaps. What I'm planning on doing is storing each bitmap in a map container with an integer key so <Integer, Bitmap> where the integer represents the index where the image should be in the list to be in correct order. I feel like I might be misusing the map container since I'm actually just storing a value pair rather than storing an object with a key so maybe there's a better data structure I could use. Is this how you guys would go about it?
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On April 19 2016 16:47 Itsmedudeman wrote:
Our university never really taught us "how" to program, just concepts and the best practices kind of stuff was left untouched unless it came up randomly. I'd love it if someone went through and reviewed code for you and told you why it's bad to do X, but you kinda just have to learn that for yourself through reading or fucking up tremendously to where your program won't work.
To my next point though... I'm working on a project which needs to store objects (bitmap images) in a list. This list gets shuffled and I need to know when this list is back in order again after various swaps. What I'm planning on doing is storing each bitmap in a map container with an integer key so <Integer, Bitmap> where the integer represents the index where the image should be in the list to be in correct order. I feel like I might be misusing the map container since I'm actually just storing a value pair rather than storing an object with a key so maybe there's a better data structure I could use. Is this how you guys would go about it?
Depends. If given the key you want access to the bitmap, then yes. But it doesn't really sound like what you want. It sounds like you want a list of bitmaps that you can shuffle (can't shuffle dictionaries), and seperately, a way of recognizing when they're back in the original order. It's worth noting that if your list is large enough and the shuffle is random, this can take a very very very long time. I'd store them in an array (or a linked list, which makes shuffling a bit faster at the cost of retrieval, but this type of optimization can wait til you figure out what are the commonly used operations, and you can profile your app to see if it makes sense), with each object in the list being a tuple (original index, bitmap).
That said, you can easily do this with an array of the bitmaps and your dictionary idea too, but it makes insert and remove operations more costly (and prone to forgetting to maintain both datastructures, introducing bugs).
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On April 19 2016 21:10 Acrofales wrote:Show nested quote +On April 19 2016 16:47 Itsmedudeman wrote:
Our university never really taught us "how" to program, just concepts and the best practices kind of stuff was left untouched unless it came up randomly. I'd love it if someone went through and reviewed code for you and told you why it's bad to do X, but you kinda just have to learn that for yourself through reading or fucking up tremendously to where your program won't work.
To my next point though... I'm working on a project which needs to store objects (bitmap images) in a list. This list gets shuffled and I need to know when this list is back in order again after various swaps. What I'm planning on doing is storing each bitmap in a map container with an integer key so <Integer, Bitmap> where the integer represents the index where the image should be in the list to be in correct order. I feel like I might be misusing the map container since I'm actually just storing a value pair rather than storing an object with a key so maybe there's a better data structure I could use. Is this how you guys would go about it? Depends. If given the key you want access to the bitmap, then yes. But it doesn't really sound like what you want. It sounds like you want a list of bitmaps that you can shuffle (can't shuffle dictionaries, and seperately, a way of recognizing when they're back in the original order. It's worth noting that if your list is large enough and the shuffle is random, this can take a very very very long time. I'd store them in an array (or a linked list, which makes shuffling a bit faster at the cost of retrieval, but this type of optimization can wait til you figure out what are the commonly used operations, and you can profile your app to see if it makes sense), with each object in the list being a tuple (original index, bitmap). That said, you can easily do this with an array of the bitmaps and your dictionary idea too, but it makes insert and remove operations more costly (and prone to forgetting to maintain both datastructures, introducing bugs).
I actually misused the word Map to mean an entry of Map, so just a key, value container rather than something like a hashmap. In java there's an AbstractMap.SimpleEntry class I can use so I was planning on using that and using them as my array elements rather than building my own class container from scratch just to hold an extra integer. It'd basically be what you were suggesting. I'm just not entirely sure if it'd be better practice to go ahead and build that class in this scenario.
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Why don't you add a pointer to the next bitmap in each entry instead of an index?
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On April 19 2016 21:10 Acrofales wrote:Show nested quote +On April 19 2016 16:47 Itsmedudeman wrote:
Our university never really taught us "how" to program, just concepts and the best practices kind of stuff was left untouched unless it came up randomly. I'd love it if someone went through and reviewed code for you and told you why it's bad to do X, but you kinda just have to learn that for yourself through reading or fucking up tremendously to where your program won't work.
To my next point though... I'm working on a project which needs to store objects (bitmap images) in a list. This list gets shuffled and I need to know when this list is back in order again after various swaps. What I'm planning on doing is storing each bitmap in a map container with an integer key so <Integer, Bitmap> where the integer represents the index where the image should be in the list to be in correct order. I feel like I might be misusing the map container since I'm actually just storing a value pair rather than storing an object with a key so maybe there's a better data structure I could use. Is this how you guys would go about it? Depends. If given the key you want access to the bitmap, then yes. But it doesn't really sound like what you want. It sounds like you want a list of bitmaps that you can shuffle (can't shuffle dictionaries, and seperately, a way of recognizing when they're back in the original order. It's worth noting that if your list is large enough and the shuffle is random, this can take a very very very long time. I'd store them in an array (or a linked list, which makes shuffling a bit faster at the cost of retrieval, but this type of optimization can wait til you figure out what are the commonly used operations, and you can profile your app to see if it makes sense), with each object in the list being a tuple (original index, bitmap). That said, you can easily do this with an array of the bitmaps and your dictionary idea too, but it makes insert and remove operations more costly (and prone to forgetting to maintain both datastructures, introducing bugs).
That would probably be my solution as well. I'd stick with an array since you can shuffle in place and so still get a constant time when switching two elements.
Have a list like
[
{
originalIndex: 0,
bitmap: bitmapdata
},
{
originalIndex: 1,
bitmap: bitmapdata2
}
]
Then you can easily check if it's ordered with
bool isOrdered = true;
for (int i = 0; i < bitmaps.length; ++i)
{
if (bitmaps[i].originalIndex != i)
{
isOrdered = false;
break;
}
}
Not sure which language you are using, but C# has a class "System.Tuple<A, B>" that can store two values in one variable without requiring a new class. However, fear of creating classes is a bad thing, so don't be afraid to create a class just for one purpose, no matter how small.
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I'm getting a weird error in some php code of mine for a hobby project.
I've created a sort function inside a class, but I get the following error whenever I try to run the codeFatal error: Cannot redeclare card_compare() (previously declared in E:\xampp\htdocs\ML\Deck.php:62) in E:\xampp\htdocs\ML\Deck.php on line 62 This is the code for the function: private function board_sort(&$board) {
function card_compare($a, $b) {
if(Deck::type_enum($a[3]) === Deck::type_enum($b[3])) {
return 0;
}
return Deck::type_enum($a[3]) < Deck::type_enum($b[3]) ? -1 : 1;
}
return usort($board, 'card_compare');
}At the moment, the only time I'm calling board_sort is twice in my class constructor. The only time card_compare is mentioned is on line 62 where I declare it and on line 68 where I call it as a parameter for usort. type_enum() is a simple workaround for enumerating strings to integers since enums aren't built into php. I am including the Deck.php file, used exclusively for defining the class, in single other php file, where I'm using require_once to include it, then creating a number of instances of the class through a loop.
I've tried google for the solution, but I've only been able to find cases where there was another function named the same, which does not seem to be the case here. I honestly how no idea what is going on, considering it how it complaining about it already being declared in the same file and line as where I am actually declaring it.
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Don't create named functions inside other functions. I didn't even knew it was possible anyways. I assume it tries to create a new function with that name every time that method is called and so on the second call it fails.
Just use
private function board_sort(&$board) {
return usort(
$board,
function($a, $b) {
if(Deck::type_enum($a[3]) === Deck::type_enum($b[3])) {
return 0;
}
return Deck::type_enum($a[3]) < Deck::type_enum($b[3]) ? -1 : 1;
}
);
}
or
private function board_sort(&$board) {
return usort($board, [$this, 'card_compare']);
}
private function card_compare($a, $b) {
if(Deck::type_enum($a[3]) === Deck::type_enum($b[3])) {
return 0;
}
return Deck::type_enum($a[3]) < Deck::type_enum($b[3]) ? -1 : 1;
}
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That was the issue. I didn't know php had anonymous functions, so now I know that as well.
Thanks for the quick answer 
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On April 19 2016 22:00 Itsmedudeman wrote:Show nested quote +On April 19 2016 21:10 Acrofales wrote:On April 19 2016 16:47 Itsmedudeman wrote:
Our university never really taught us "how" to program, just concepts and the best practices kind of stuff was left untouched unless it came up randomly. I'd love it if someone went through and reviewed code for you and told you why it's bad to do X, but you kinda just have to learn that for yourself through reading or fucking up tremendously to where your program won't work.
To my next point though... I'm working on a project which needs to store objects (bitmap images) in a list. This list gets shuffled and I need to know when this list is back in order again after various swaps. What I'm planning on doing is storing each bitmap in a map container with an integer key so <Integer, Bitmap> where the integer represents the index where the image should be in the list to be in correct order. I feel like I might be misusing the map container since I'm actually just storing a value pair rather than storing an object with a key so maybe there's a better data structure I could use. Is this how you guys would go about it? Depends. If given the key you want access to the bitmap, then yes. But it doesn't really sound like what you want. It sounds like you want a list of bitmaps that you can shuffle (can't shuffle dictionaries, and seperately, a way of recognizing when they're back in the original order. It's worth noting that if your list is large enough and the shuffle is random, this can take a very very very long time. I'd store them in an array (or a linked list, which makes shuffling a bit faster at the cost of retrieval, but this type of optimization can wait til you figure out what are the commonly used operations, and you can profile your app to see if it makes sense), with each object in the list being a tuple (original index, bitmap). That said, you can easily do this with an array of the bitmaps and your dictionary idea too, but it makes insert and remove operations more costly (and prone to forgetting to maintain both datastructures, introducing bugs). I actually misused the word Map to mean an entry of Map, so just a key, value container rather than something like a hashmap. In java there's an AbstractMap.SimpleEntry class I can use so I was planning on using that and using them as my array elements rather than building my own class container from scratch just to hold an extra integer. It'd basically be what you were suggesting. I'm just not entirely sure if it'd be better practice to go ahead and build that class in this scenario.
A Map is a Map is a Map. Don't confuse your conceptual datastructures with your implemented datastructures (although i guess my original post kinda invited that by going into the details of what list implementation is better). A Map, inherently, is a datastructure that has two sets, and a surjective function between them. In (mathematical) theory, the surjection is not required (any function will do), but in computing, it'd be extremely weird for your map to not be surjective (often, in fact, your map will be bijective, as is the case in your example).
Now your map has to be implemented in some way. The usual Java implementation is with a hash table (Hashmap), but as you say, there are many other ways of doing this. For instance, you could create a horribly inefficient Map by storing your keys in one array, and your objects in another array. Your lookup could then find the key in the first array, and return the element at the same index in the object array. This has an O(n) average efficiency for search and for delete, whereas a hash table has O(1) average efficiency for those operations.
Now I realize this is all a tangent, as it seems you weren't interested in Map at all, but some nested class of the Java SDK's AbstractMap. You can obviously do this, but it seems rather silly. The reason why is best explained by referring to a recent fubar concerning Node.js libraries (and while the Java SDK is a lot better maintained than Node.js random assortment of libraries, the philosophy is similar):
http://www.haneycodes.net/npm-left-pad-have-we-forgotten-how-to-program/
Every package that you use adds yet another dependency to your project. Dependencies, by their very name, are things you need in order for your code to function. The more dependencies you take on, the more points of failure you have. Not to mention the more chance for error: have you vetted any of the programmers who have written these functions that you depend on daily?
Take on a dependency for any complex functionality that would take a lot of time, money, and/or debugging to write yourself. Things like a database access layer (ORM) or caching client should be dependencies because they’re complicated and the risk of the dependency is well worth the savings and efficiency.
Not to mention, the confusion that this adds for someone debugging or extending the code (probably you in 6 months time). You'll be looking at the code asking yourself where the Map is that makes use of these AbstractMap.SimpleEntry objects, and how you can extend this to not only store a bitmap, but also a textual descriptor of the image. If, however, you write your own nested class with about 10 lines of code (most of it autogenerated by your IDE), and give it a sensible name (e.g. OrderedBitmap), then you won't have to worry about this. You also won't have to worry about Oracle deprecating AbstractMap.SimpleEntry in a future Java version (not that that seems likely to happen, but presumably the programmers using the padleft "library" didn't expect that to get removed from github either).
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On April 19 2016 22:32 Blitzkrieg0 wrote:
Why don't you add a pointer to the next bitmap in each entry instead of an index?
While that will obviously work too to maintain the original order (there's more than one way to skin a cat), I don't see the advantage?
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On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks.
Someone correct me if I am wrong, but to be pedantic the code you supplied could work and depends entirely on the context, such as the modifiers of the method. If
Classname1.doSomethingWhichAccessesAttributes();
is static and is correctly written (i.e. uses static attributes only) then it is correct. This means that this line:
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
could also work if this same static method returns a ClassType of Classname1.
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GRAND OLD AMERICA16375 Posts
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On April 20 2016 00:38 carmon wrote:Show nested quote +On April 18 2016 05:32 waffelz wrote:...Here I sit, explaining a 4.th semester computer science student why
Classname1.doSomethingWhichAccessesAttributes();
doesn't work, only to get asked by the same student just a bit later why
Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes();
doesn’t work... I am not a big fan of java myself, but at least it saves me from always answering the same questions regarding pointers and references... and this particularly mistake has nothing to do with any of javas quirks. Someone correct me if I am wrong, but to be pedantic the code you supplied could work and depends entirely on the context, such as the modifiers of the method. If Classname1.doSomethingWhichAccessesAttributes(); is static and is correctly written (i.e. uses static attributes only) then it is correct. This means that this line: Classname1 myClass = Classname2.doSomethingWhichAccessesAttributes(); could also work if this same static method returns a ClassType of Classname1.
Yes. But unfortunately this was neither the reason for said student to make this mistake, nor did he understood the situation like you. And in both cases said student was just plain wrong.
I wish I had more people like you in the groups I oversee 
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On April 19 2016 23:46 Acrofales wrote:Show nested quote +On April 19 2016 22:32 Blitzkrieg0 wrote:
Why don't you add a pointer to the next bitmap in each entry instead of an index? While that will obviously work too to maintain the original order (there's more than one way to skin a cat), I don't see the advantage?
Simplicity mainly. I think shuffling my solution kinda loses its meaning though.
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How to gain experience without job?
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EPT
