# DidaWiki

### Strumenti Sito

magistraleinformaticanetworking:spm:skepu-map

### SKEPU map sample code

skepu_map.cpp
#include <iostream>

#define SKEPU_CUDA

#include "skepu/vector.h"
#include "skepu/matrix.h"
#include "skepu/map.h"

using namespace std;

// definition of functions to be used in the map and reduce

UNARY_FUNC(inc,  int, a, return(a+1); )
UNARY_FUNC(dec,  int, a, return(a-1); )
UNARY_FUNC(sq,   int, a, return(a*a); )
BINARY_FUNC(add, int, a, b, return(a+b); )
BINARY_FUNC(sub, int, a, b, return(a-b); )
BINARY_FUNC(mul, int, a, b, return(a*b); )
BINARY_FUNC(div, int, a, b, return(a/b); )

#define N 4

int main()
{
// declare vectors
skepu::Vector<float> v0(N);
skepu::Vector<float> v1(N);
skepu::Vector<float> v2(N);

// initialize the vector(s) to some meaningful value
for(int i=0; i<N;i++) {
v0[i]=i+1;
v1[i]=-(i+1);
}
cout << "Initial array: " << v0 << endl;

// one input map: forall i compute f(v0[i])
skepu::Map<sq> sqmap(new sq);
sqmap(v0,v2);
cout << "After sqmap:   " << v2 << endl;

// two input map: forall i compute f(v0[i],v1[i])
// same as: alpha(f) o zip
}