It is sample code from http://softwareandfinance.com/CPP_3D_Dynamic_Arrays.html
for creating dynamic arrays. Hope this helps...!
template<class Type>
int Create3D_Array(Type ****pResult, int x, int y, int z)
{
Type ***p = new Type **[x];
for(int i = 0; i < x; i++)
{
p[i] = new Type *[y];
for(int j = 0; j < y; j++)
p[i][j] = new Type[z];
}
*pResult = p;
return x * y * z;
}
template<class Type>
int Delete3D_Array(Type ****pResult, int x, int y, int z)
{
Type ***p = *pResult;
for(int i = 0; i < x; i++)
for(int j = 0; j < y; j++)
delete p[i][j];
for(int i = 0; i < x; i++)
delete p[i];
delete p;
return 0;
}
void TestFunc()
{
int ***pInt = NULL;
float ***pFloat = NULL;
Create3D_Array(&pInt, 2, 4, 6);
Create3D_Array(&pFloat, 2, 3, 5);
int count = 0;
for(int i = 0; i < 2; i++)
{
for(int j = 0; j < 3; j++)
for(int k = 0; k < 5; k++)
pFloat[i][j][k] = count += 3;
}
for(int i = 0; i < 2; i++)
{
for(int j = 0; j < 3; j++)
{
for(int k = 0; k < 5; k++)
{
char buf[512];
sprintf(buf, "Array[%d][%d][%d] = %.2f\n", i, j, k,
pFloat[i][j][k]);
std::cout << buf;
}
}
}
Delete3D_Array(&pFloat, 2, 3, 5);
Delete3D_Array(&pInt, 2, 4, 6);
}
--- In [email protected], "Gerald Dunn" <dun...@...> wrote:
>
> Admittedly I don't know why it works in one environment and not the other for
> you. My understanding is you can only reserve memory on the stack with
> constant values that are known at compile time. In your example you provided:
>
> int sampleTest = 1;
> Vector3D randomArray[sampleTest];
>
> Rob was suggesting using a #define because that provides a constant value.
> The preprocessor would replace 'SAMPLE_SIZE' with (in his example) '1'. Since
> you've told the compiler where to find the definition of a Vector3D it
> therefore knows its size, knows there's an array of '1' and can therefore
> allocate an array of constant size.
>
> However, it seems your example was just to express what you were trying to
> accomplish. After reading your last post it seems you're really going for
> something more like:
>
> void someFunction(int size) {
> Vector3D randomArray[size];
> }
>
> If you need an array with a dynamic size then you will most likely need:
>
> void someFunction(int size) {
> Vector3D *randomArray = (Vector3D*) malloc(size * sizeof(Vector3D));
>
> // do stuff ...
>
> free((void*) randomArray);
> }
>
> Granted, that doesn't check '0 < size'. My solution was more C. As for C++
> I'm not an expert but if your Vector3D is a class then you will probably need
> to inialize your array somehow using 'new'.
>
> I hope this helps. Thanks. Jerry.
>
> ----- Original Message -----
> From: Jos Timanta Tarigan
> To: [email protected]
> Sent: Tuesday, August 03, 2010 2:18 PM
> Subject: Re: [c-prog] array initialization
>
>
>
> hi,
>
> the problem is the vlaue is not a constant. its an input from a
> SetSampleQuantity(int input) method. so it has to be defined at run time
> (user
> input specifically) . this method called in the beginning whne the program
> is
> called. how can i do that? any way to do that?
> this is very weird considering it works fine on os x environment.
> =================================
> http://www.svnstrk.blogspot.com
>
> ________________________________
> From: Rob Richardson <rob.richard...@...>
> To: [email protected]
> Sent: Tue, August 3, 2010 7:13:55 PM
> Subject: RE: [c-prog] array initialization
>
> Since you have to rebuild this code every time you change the sampleTest
> value, you might as well use a copiler constant instead of a constant
> whose value is not known until run time:
>
> #define SAMPLE_SIZE 1
> Vector3D randomArray[SAMPLE_SIZE];
>
> RobR
>
> [Non-text portions of this message have been removed]
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
