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[Big Chungus]

recursion is kicking my ass

D:

 

[toddhunter]

What's OO?

Object oriented. Once you wrap your head around the whats and whys you can adapt it to a lot of languages.

 

[lorebringer]

recursion is kicking my ass

D:

Recursion is the most natural way to think about most problems. What about it is giving you trouble?

Spoiler

I love me some recursion

 

[Fantastical]

recursion is kicking my ass

D:

Yeah, recursion still gets me sometimes.

 

[Onemic]

Object oriented. Once you wrap your head around the whats and whys you can adapt it to a lot of languages.

Is there any resource that teaches that? And isn't that something that's apart of C# and C++?

 

[Jokab]

Is there any resource that teaches that? And isn't that something that's apart of C# and C++?

Any beginner book on an object-oriented language (Java, C++, C# to name a few) will thoroughly teach you OOP. And yes, C# and C++ are definitely very object-oriented.

 

[Slavik81]

Recursion is the most natural way to think about most problems. What about it is giving you trouble?

Spoiler

I love me some recursion

Recursion: easy to write; difficult to write well.

They have only made 6 posts and they've all been spam, going back a year.

I blame m.neogaf for my failings.

 

[pompidu]

Ignore

 

[Onemic]

Any beginner book on an object-oriented language (Java, C++, C# to name a few) will thoroughly teach you OOP. And yes, C# and C++ are definitely very object-oriented.

Well I'm currently going through the Javascript course at codeacademy, would that be enough or would it be best to use more resources?

 

[squidyj]

recursion is kicking my ass

D:

Recursion is a joy!, a joy!

oh Haskell!

But seriously what's troubling you?


pompidu..... It looks like all that happens when you press the search button right now is it grabs whatever is in your text fields into a number of Strings and does nothing with that data.
seems like you want to take that string data, convert it to double or int, use that to build a criteria and use your new criteria to print a selection of houses to. thankfully there's a handy method in the Integer wrapper class and one just as good for doubles.

Integer.parseInt(String s)
Double.parseDouble(String s)

which takes a string and returns its integer value.

I might also add that as per your tester class you don't really need to declare labels for those criteria.

houseList.printHouses(new Criteria (1000, 505000, 100, 5000, 0, 10)); //valid instruction

 

[ComputerMKII]

Well I'm currently going through the Javascript course at codeacademy, would that be enough or would it be best to use more resources?

Just learn Java.

 

[Randolph Freelander]

Well I'm currently going through the Javascript course at codeacademy, would that be enough or would it be best to use more resources?

If Edsger Dijkstra were alive today, he might update his quote to say "It is practically impossible to teach good programming to students that have had a prior exposure to BASIC Javascript: as potential programmers they are mentally mutilated beyond hope of regeneration."

 

[TheFeedingHand]

Well I'm currently going through the Javascript course at codeacademy, would that be enough or would it be best to use more resources?

Start with C. Every other imperative language will seem easy after that.

 

[DUFFMCWALIN]

I've always used VMware, do you prefer virtualbox?

I think vmware is probably better but I've just had nightmares with it over the years. Probably because I have not thrashed it as much, vb has been good to me

parallels if you have a mac is a good option. I have a windows 8 and fedora VM on ML and it works great.

 

[AnathemicOne]

Anyone in C++ know the variable for the value of Pi (3.14....)? The book doesn't have it and I have to use it to do one of the equations/programs in the book.

 

[ComputerMKII]

Anyone in C++ know the variable for the value of Pi (3.14....)? The book doesn't have it and I have to use it to do one of the equations/programs in the book.

Isn't Pi a constant?

 

[Godslay]

Anyone in C++ know the variable for the value of Pi (3.14....)? The book doesn't have it and I have to use it to do one of the equations/programs in the book.

You could define a constant with the double PI = 22/7. It's an approximation, but it will work.

Isn't Pi a constant?

Not in standard C++ or C from what I was able to gather.

 

[smokeandmirrors]

Anyone in C++ know the variable for the value of Pi (3.14....)? The book doesn't have it and I have to use it to do one of the equations/programs in the book.

I think under <math.h> it's listed as M_PI

or use atan(1) * 4 and cache it that way.

 

[Slavik81]

Anyone in C++ know the variable for the value of Pi (3.14....)? The book doesn't have it and I have to use it to do one of the equations/programs in the book.

There's no official constant for it, but you might find M_PI in math.h

On Windows with Microsoft's headers there's a define you need to enable, too: _USE_MATH_DEFINES

 

[AnathemicOne]

You could define a constant with the double PI = 22/7. It's an approximation, but it will work.



Not in standard C++ or C from what I was able to gather.

I think under <math.h> it's listed as M_PI

or use atan(1) * 4 and cache it that way.

There's no official constant for it, but you might find M_PI in math.h

On Windows with Microsoft's headers there's a define you need to enable, too: _USE_MATH_DEFINES

Thanks for the replies, since there's no variable I can draw off from predetermined library I just decided to set it as a constant double at 3.14159, hopefully that works.

 

[Memento_Mori15]

Noob question incoming:
Do I always have to initialize a new scanner if I want to read a different input from the user or can I use the same one?
Example:

Scanner sc = new Scanner(System.in);
System.out.println("How many items do you want?");
order= sc.nextInt();
System.out.println("would you like express shipping?");
Scanner ans = new Scanner(System.in);
answer=ans.nextLine();
if (answer.equals("yes")){
//rest of code

I had to add the second scanner because it wouldn't let me type something in before in the command prompt.

And the main methods can't access instance variables? Only locals, right? Just want to be sure.

 

[Lkr]

we're making a cash register program as an assignment. anyway, my problem is that when making a case for store credit, i set tax to 0, price and total are the same value for this. everything is fine. everything is a double stored in the array. when i go to print, it prints out price and tax just fine, but it prints total as say 10.00 and then prints a memory address right next to it. only happens here, if i do a normal item everything is fine. setprecision doesn't help either. i know this is very vague, but i'm pretty upset about this

 

[Godslay]

we're making a cash register program as an assignment. anyway, my problem is that when making a case for store credit, i set tax to 0, price and total are the same value for this. everything is fine. everything is a double stored in the array. when i go to print, it prints out price and tax just fine, but it prints total as say 10.00 and then prints a memory address right next to it. only happens here, if i do a normal item everything is fine. setprecision doesn't help either. i know this is very vague, but i'm pretty upset about this

Show us some code. Sounds like you are outputting the address rather than the value at the address.

 

[Lkr]

Show us some code. Sounds like you are outputting the address rather than the value at the address.

is there a reason it would only happen with the credit option though? its the same exact code for every other type of item, the only difference being that if it is credit that the tax is 0 and the total and price variables have the same value. i'm just printing it through a for loop

for(int i = 0; i < Size; i++
{
  cout << MyArray.Price() << " " << MyArray.Total();
}

Price and Total are just functions that return the value of a private variable

 

[Lasthope106]

is there a reason it would only happen with the credit option though? its the same exact code for every other type of item, the only difference being that if it is credit that the tax is 0 and the total and price variables have the same value. i'm just printing it through a for loop

for(int i = 0; i < Size; i++
{
  cout << MyArray.Price() << " " << MyArray.Total();
}

Price and Total are just functions that return the value of a private variable

We need more code than that. What is MyArray storing? Is it an array of objects that you are using to store a transaction?

 

[DragonSworne]

is there a reason it would only happen with the credit option though? its the same exact code for every other type of item, the only difference being that if it is credit that the tax is 0 and the total and price variables have the same value. i'm just printing it through a for loop

for(int i = 0; i < Size; i++
{
  cout << MyArray.Price() << " " << MyArray.Total();
}

Price and Total are just functions that return the value of a private variable

Is that an actual code snippet? Because you are missing an ending parenthesis in the for loop after i++ and you aren't even using the variable to traverse the array. Don't you need MyArray.Price() and so on...

 

[DragonSworne]

We need more code than that. What is MyArray storing? Is it an array of objects that you are using to store a transaction?

I'm assuming so since he is calling a function

Plus he said function not method. Is this C or C++?

 

[Godslay]

Is that an actual code snippet? Because you are missing an ending parenthesis in the for loop after i++ and you aren't even using the variable to traverse the array. Don't you need MyArray.Price() and so on...

In addition to this, how are you storing the size for the loop? Just to make sure it is looping through all the items.

 

[Lkr]

Is that an actual code snippet? Because you are missing an ending parenthesis in the for loop after i++ and you aren't even using the variable to traverse the array. Don't you need MyArray.Price() and so on...

no, i just typed an example of my code. i really can't post it because they'll scan for plagarism crap. basically i call everything fine in the program.
there are four types of transactions that can be made. for the other three, everything works fine using the same method. for this fourth one, it just randomly prints a memory address after it prints the correct value. i'll probably have my teacher look at it tomorrow, it is just driving me crazy, sorry
c++, and the CurrentSize stores the size of the array(it is dynamic)

 

[toddhunter]

Noob question incoming:
Do I always have to initialize a new scanner if I want to read a different input from the user or can I use the same one?
Example:

You can generally use the same one...however nextInt and nextLine do not mix well. Basically nextInt does not consume the whole line (the carriage return at the end).

A good practice is to only use nextLine (and turn it into an int if required), or to have two scanners, one for lines and one for ints. Otherwise it all gets pretty messy .

And the main methods can't access instance variables? Only locals, right? Just want to be sure.

Locals and static variables.

 

[Vic]

Finally figured out how to run a basic C++ program on Linux. This is promising!

 

[Godslay]

no, i just typed an example of my code. i really can't post it because they'll scan for plagarism crap. basically i call everything fine in the program.
there are four types of transactions that can be made. for the other three, everything works fine using the same method. for this fourth one, it just randomly prints a memory address after it prints the correct value. i'll probably have my teacher look at it tomorrow, it is just driving me crazy, sorry
c++, and the CurrentSize stores the size of the array(it is dynamic)

What is the memory address it is outputting? I wonder if you are going one too far on your array?

For example, this:

int myArray [3];

	for (int i= 0; i < 3; i++)
	{
		myArray[i] = i;
	}

	for (int i = 0; i < 4; i++)
	{
		cout << " " << myArray[i];
	}

Will output this:

 

[DragonSworne]

no, i just typed an example of my code. i really can't post it because they'll scan for plagarism crap. basically i call everything fine in the program.
there are four types of transactions that can be made. for the other three, everything works fine using the same method. for this fourth one, it just randomly prints a memory address after it prints the correct value. i'll probably have my teacher look at it tomorrow, it is just driving me crazy, sorry
c++, and the CurrentSize stores the size of the array(it is dynamic)

Did you overload your transaction class constructor?

Can you post examples of the signatures and what you are passing in when creating a credit transaction?

Edit - try setting tax to 0.0 instead of 0

 

[Godslay]

Did you overload your transaction class constructor?

Can you post examples of the signatures and what you are passing in when creating a credit transaction?

Edit - try setting tax to 0.0 instead of 0

I think we lost him! I agree though something is either not getting initialized, or he is going looping beyond the bounds of the array and outputting garbage. At least that would be my guess without being able to see the actual innards.

 

[Why would you do that?]

For the first time, I am almost completed with a game in Java (yay), but after this, I really want to learn C.

For some strange reason, Java is easy, Python is easy, and (6502) ASM is easy and fun from my limited time with it, but I am having problems learning C and especially C++. I have no idea what it is that bothers me about those languages...

Did/does anyone else feel that way?

 

[DragonSworne]

For the first time, I am almost completed with a game in Java (yay), but after this, I really want to learn C.

For some strange reason, Java is easy, Python is easy, and (6502) ASM is easy and fun from my limited time with it, but I am having problems learning C and especially C++. I have no idea what it is that bothers me about those languages...

Did/does anyone else feel that way?

Nope, I found both C ad C++ straight forward and simple while programming languages like Java to be bloated.

Although I'm now a Java programmer for a living, still prefer C++.

 

[toddhunter]

Nope, I found both C ad C++ straight forward and simple while programming languages like Java to be bloated.

Although I'm now a Java programmer for a living, still prefer C++.

Did you start with Java? If you did I think C and C++ are quite difficult to wrap your head around. Pointers especially are a stumbling block for people going back.

 

[DragonSworne]

Did you start with Java? If you did I think C and C++ are quite difficult to wrap your head around. Pointers especially are a stumbling block for people going back.

No, I started with C then moved on to C++

What frustrated me when learning Java are all the hoops you have to jump through to get things accomplished, especially things that are relatively easy to do in C or C++.

Once you understand and get use to how things are done in Java, it's an awesome language.

 

[Why would you do that?]

I understand the pointers. I haven't had much hands-on time with C, so I'm no expert, but... I guess there's just something about the language and the way people use it that seems intimidating and complicated.

 

[rooflapimp]

Nope, I found both C ad C++ straight forward and simple while programming languages like Java to be bloated.

Although I'm now a Java programmer for a living, still prefer C++.

Say what you will about Java vs C++, but the latter is definitely an extremely bloated language.

Come to think of it, I believe this is the first time I have ever heard anyone call C++ "straight forward and simple" compared to Java.

 

[Slavik81]

For the first time, I am almost completed with a game in Java (yay), but after this, I really want to learn C.

For some strange reason, Java is easy, Python is easy, and (6502) ASM is easy and fun from my limited time with it, but I am having problems learning C and especially C++. I have no idea what it is that bothers me about those languages...

Did/does anyone else feel that way?

The things I had trouble with:
- symbol linkage
- implicit type promotions
- special rules for c-style arrays
- poor compiler error messages, especially for templates

Years later I still think a lot of these are the fault of the language and the tools. Clang and C++11 are fixing some things, but a lot of it runs deep into the language.

Still I do like them. I've learned the idiosyncrasies now, so I've paid that cost. I feel like I mostly understand what is happening when I use C++, so I'll likely use it for a long time to come.

 

[Anson225]

i'm trying to teach myself programming, but i don't have any previous experience. which would be an appropriate language for me to start with and lay a good foundation? thanks

 

[toddhunter]

i'm trying to teach myself programming, but i don't have any previous experience. which would be an appropriate language for me to start with and lay a good foundation? thanks

What is the driver behind you learning?

 

[Lonely1]

I suddenly found myself giving a class on programing and I fell that my performance is less than satisfactory.

They are third year students on CS, so they are supposed to know their way around programming by know. So, the approach I took was to prepare examples on how to do things that I consider that are relevant in order to understand the language and paradigm (functional). I even code some traps inside my code in order to ask them questions like "Can anyone tell my why doing that is a bad idea? How can we improve it?" Yet, I barely get any feedback. I feel trapped in dull monologue, reading and trying to explaining line of code after line of code, without any hint if my explanation terrible.

Doesn't help that I didn't payed attention to my programing courses when I was a student, since I preferred a hands on approach. You can say I considered the courses I took almost as dull as my own.

Any tips, programming GAF?

 

[Anson225]

What is the driver behind you learning?

just hobby, was thinking it is a great skill to have

 

[EekumBokum]

In C, does anyone know how to make a void type function return a reversed string to main? I just can't get this working properly. And I can't use any string functions.

 

[Salsa]

ive been learning Java wich I knew nothing of on codecademy for the last day or two

what a fantastic tool

 

[rooflapimp]

In C, does anyone know how to make a void type function return a reversed string to main? I just can't get this working properly. And I can't use any string functions.

I haven't tested this, but something like this should work.

void reverse(char* s)
{
	char* p = s;
	int len = 0;
	char c;

	while (*p++)
	    len++;
			
	for (int i = 0, j = len-1; i < j; ++i, --j) {
	    c = s[i];
	    s[i] = s[j];
	    s[j] = c;
	}
}

 

[squidyj]

I suddenly found myself giving a class on programing and I fell that my performance is less than satisfactory.

They are third year students on CS, so they are supposed to know their way around programming by know. So, the approach I took was to prepare examples on how to do things that I consider that are relevant in order to understand the language and paradigm (functional). I even code some traps inside my code in order to ask them questions like "Can anyone tell my why doing that is a bad idea? How can we improve it?" Yet, I barely get any feedback. I feel trapped in dull on a monologue, reading and trying to explaining line of code after line of code, without any hint if my explanation terrible.

Doesn't help that I didn't payed attention to my programing courses when I was a student, since I preferred a hands on approach. You can say I considered the courses I took almost as dull as my own.

Any tips, programming GAF?

I have seen first hand some attempts to get students involved. It always turned out awkward and embarrassing. Personally I wouldn't mind learning from lectures if it wasn't so goddamn slow, I read a good set of lecture notes in 15 minutes, maybe there's a problem in there I work out and I already know the lecture better than I would have if I had sat in the class and listened to the professor talk for an hour.

I know why I don't want to say shit in class, First of all I don't want to be wrong, second of all I don't want to be that guy with all the answers, third, I'm probably not even paying attention to your lecture and am currently browsing NeoGAF on my laptop, sorry.

-Signed, 3rd Year Comp Sci student currently taking Paradigms.

 

[EekumBokum]

I haven't tested this, but something like this should work.

void reverse(char* s)
{
	char* p = s;
	int len = 0;
	char c;

	while (*p++)
	    len++;
			
	for (int i = 0, j = len-1; i < j; ++i, --j) {
	    c = s[i];
	    s[i] = s[j];
	    s[j] = c;
	}
}

It worked! Thank you!