CUBLAS question Need help with some matrix column inner product

Accelerated Computing CUDA CUDA Programming and Performance
1

Hello,

I had posted this on the wrong form. So apologies for that.

I have a simple C function that computes the inner product between the part of a column of a rectangular matrix with the corresponding part of a column of another rectangular matrix.

The code in C is simply as follows:

[codebox]

double inner_mat_col( int l, int u, int i, int j, double a, double b )

{

double s = 0.0;

for (; l < u; ++l) s+= a[l][i] * b[l][j]);

return s;

}

[/codebox]

The code here is very simple. I am just iterating through all the column vector elements in a and the column vector elements in b (the column in a is specified by the index i and the column in b is specified by index j) and accumulating the product.

Is there a simple way to do the equivalant in CUBLAS. I have been tinkering around with CUDA for a few months but I have no experience with CUBLAS and I would be really grateful for some pointers.

Thanks for any help you can give me,

Luca

2

Well, you can use cublasSdot (single precision) or cublasDdot (double precision).

3

Well, you can use cublasSdot (single precision) or cublasDdot (double precision).