MacResearch

Good Evening,

I try to write a simple program which will sum up all numbers of a matrix and return the number. So far I know that OpenCL Kernels can not return itself a value, so I thought of this:

__kernel void sum(__global float *inputmatrix,int N,__global float *summe){
int i;
float test;
test = 0.0f;
for(i=0;i.lt.N*N;i++){
test = test + inputmatrix[i];
}
summe = test;}

but now, which arguments should I fill in in my main for this.
More precisley I´m confused about cl_mem vs cl_float, I tried (very naive I know) a cl_float variable for my summe but it didn´t work.
Please can someone explain the cl_mem vs cl_float in more detail ? (I need sums of matrixes in a further program and there I also have to calculate with these numbers in main again ...)

best regards