Hello,
I want to write a function that should return 2 arrays of size 10 and type double i.e a[10] and b[10]. Is that even possible. If yes, can somebody show me an example? A very rough prototype of my requirement is shown below:


Thanks,
prads

I am pretty sure it is possible (forgive my ignorance, I don't program in C/C++ much), just not the way you are attempting it. When you call a return it exits the function right after the return is complete, meaning that right now your code it returning a[] and not the second line. What I would try (If I was you) is to combine the 2 arrays into a single, multidimensional array so that it can be returned in a single line of code, then split them apart afterwards.

Something like so:



Then you can split them outside of the function lik eos:


(Or however it works in C)

As I said, I am not a pro at C/C++, but that is the basic idea that I would use.

Hope that helps.

I don't think you can return 2 objects from a function.

You could concatanate them and return a single array and split it at a later point. Assuming they're arrays of the same type.

A better option might be to make a struct that contains 2 array and return that struct type.

As beta said you can't return two things back to main. However when you create arrays the name is a pointer:

double nums[10];

nums is a constant double pointer, and its pointing to the first element in the array. If you need to input values into the array in your function you need to pass the "array" to your function. When you pass the name of the array to the function your actually passing a pointer. This gives you the power to change the array.

I'm assuming this is what you are trying to do. Declare your two arrays in main and pass them to your functions so you can populate them maybe this will get you started:

void populateArray(double [], double[], ....);

of course your prototype may not look like this because I don't know exatcly what you're trying to do. But that is what your prototype should look like if your passing arrays.

Mallstrops idea is good too, might be the best option, but if it's for a homework assignment you should do exactly what the problem asks. If your doing it just for you, then I'd say a structure would be the best option.

This post has been edited by tortillaboy05: 3 Jul, 2008 - 09:28 AM

Concatenate the two arrays, and add a token to seperate them.

For example, if array1 = "Danny" and array2 = "gabehabe" then array3 = "Danny|gabehabe"

Then, split it again after returning (in your main)

Also, if you only want to edit the actual values stored in that array, you could pass a pointer to array1 and change the actual values being stored, and then your function could return void.

Honestly I would say the easiest way to do it would be to pass two arrays in as parameters and do it that way. For example, if you didn't want to edit the arrays that you send if just send in two empty arrays:

void myfunc(double array1[], double array2[], double result1[], double result2[])

And I believe in C/C++ arrays are automatically pass by reference so this should work? Hopefully

Any code after a call to "return" will not be executed, because "return" exits the function.

Depending on which compiler (and which compiler flags you're using), you should be warned about "unreachable code".

A "double" is a kind of number btw, which stands for double precision. It doesn't mean two variables.

If you want to modify two arrays, pass pointers to them as parameters to the function.