With multidimensional arrays greater than 150x150, I get a range violation at
run time: "core.exception.RangeError@pweight(54): Range violation"
Is this a bug? Is there a work-around?

On Mon, 28 Feb 2011 16:07:41 +0000, Dr.Smith wrote:

> With multidimensional arrays greater than 150x150, I get a range violation at run time: "core.exception.RangeError@pweight(54): Range violation" Is this a bug? Is there a work-around?

Can you show some code or a test case?

My sample below seems to work fine (but I'm still using an older dmd - v2.049):

	int[151][151] x;

	x[150][150] = 7;
	writeln(x[150][150]);

For example:

double [string] data;
double [200][1000] data2;

for(int i = 0; i < 200; i++) {
    for(int j = 0; j < 1000; j++) {

      // fake multi-dim works
      string str = to!string(i) ~ "," ~ to!string(j);
      data[str] = someNumber;

      // real multi-dim does not work
      data2[i][j] = someNumber;
    }
}

Dr.Smith:

> For example:
> 
> double [string] data;
> double [200][1000] data2;
> 
> for(int i = 0; i < 200; i++) {
>     for(int j = 0; j < 1000; j++) {
> 
>       // fake multi-dim works
>       string str = to!string(i) ~ "," ~ to!string(j);
>       data[str] = someNumber;
> 
>       // real multi-dim does not work
>       data2[i][j] = someNumber;
>     }
> }

You receive the same stack overflow error with this simpler code:

void main() {
    double[200][1000] a;
}

Keep in mind this is a fixed-sized array, so it's allocated on the stack.

On Windows with DMD if you add a switch like this, to increase max stack size, that code works: -L/STACK:10000000

Bye,
bearophile

That's because data2 has length 1000, each of which has an array of length 200. Not the other way around. This works:

double[200][1000] data2;

void main()
{
    for(int i = 0; i < 1000; i++) {
        for(int j = 0; j < 200; j++) {
         data2[i][j] = 4.0;
       }
    }
}