What is the different between Texture and Constant memory?

[Amir_Baruh]

and How can I use double in Texture memory?
Thanks

[jph4599]

You can convert the double to an int2 as suggested in the CUDA 2.1 FAQ post.

Can I read double precision floats from texture?

The hardware doesn’t support double precision float as a texture format, but it is possible to use int2 and cast it to double as long as you don’t need interpolation:

texture<int2,1> my_texture;

static inline device double fetch_double(texture<int2, 1> t, int i)

{

int2 v = tex1Dfetch(t,i);

return __hiloint2double(v.y, v.x);

}

You can use a union on the host side to convert double to int2:

union doubleToint2

{

	double	 d;

	signed int i[2];

};