def cSelect():
    """
    Return the kernel source of cSelect. 
    """
    R = """
        KERNEL void cSelect(
        GLOBAL_MEM const  int *order1,
        GLOBAL_MEM const  int *order2,
        GLOBAL_MEM const float2 *indata,
        GLOBAL_MEM       float2 *outdata)
        {
        const unsigned int gid=get_global_id(0); 
        outdata[order2[gid]]=
                   indata[order1[gid]];
        };
        """
    return R
