Thread: from 2D pointer to 1D array

Hi,

I am trying to assign an array of pointer the values of a pointer to pointer, but can´t get it right.

This is what I have :

float **vars_array coming from the function arguments of size 3 x nnodes. Also nnodes comes as argument of the function.

This is what I have now and is working properly:

Code:

void wrt2VTK_unstr(float **vars_array, int nnodes)
{

	unsigned int i;

	float vars1[nnodes], vars2[nnodes], vars3[nnodes];

	
	//LOOP VARS:
	for(i = 0; i<nnodes; i++){
		vars1[i] = vars_array[i+1][0]; 
		vars2[i] = vars_array[i+1][1]; 
		vars3[i] = vars_array[i+1][2]; 

	}
	
	//vars[]
	float *vars[] = {vars1, vars2, vars3};

return 0;
}

but what I need to do is, INSTEAD of assigning *vars[] with the arrays vars1, vars2, and vars3, I want to assign *vars[] directly with vars_array[1:nnodes][0], vars_array[1:nnodes][1], vars_array[1:nnodes][2].

How can I pass these "2D" pointers to *vars[] ?

thank you in advance,
Best
cfd

Well, this isn't Fortran. vars_array[1:nnodes][0] is not a contiguous bunch of memory; vars_array[0][0:2] would be a contiguous bunch of memory and you could assign vars_array[0] to something if you wished. But you can't get to columns of a matrix, except as you have done.

Hi Tabstop,

thank you for the information

Best regards