GPU Computing with Python: PyOpenCL and PyCUDA Updated

2011/07/04 JeGX

GPU Computing with Python

PyOpenCL and PyCUDA, two wrappers for OpenCL and CUDA APIs, have been updated. These wrappers allow to call OpenCL and CUDA functions from a Python code.

PyOpenCL: OpenCL + Python

PyCUDA: CUDA + Python

PyOpenCL sample:

import pyopencl as cl
import numpy
import numpy.linalg as la
 
a = numpy.random.rand(50000).astype(numpy.float32)
b = numpy.random.rand(50000).astype(numpy.float32)
 
ctx = cl.create_some_context()
queue = cl.CommandQueue(ctx)
 
mf = cl.mem_flags
a_buf = cl.Buffer(ctx, mf.READ_ONLY | mf.COPY_HOST_PTR, hostbuf=a)
b_buf = cl.Buffer(ctx, mf.READ_ONLY | mf.COPY_HOST_PTR, hostbuf=b)
dest_buf = cl.Buffer(ctx, mf.WRITE_ONLY, b.nbytes)
 
prg = cl.Program(ctx, """
    __kernel void sum(__global const float *a,
    __global const float *b, __global float *c)
    {
      int gid = get_global_id(0);
      c[gid] = a[gid] + b[gid];
    }
    """).build()
 
prg.sum(queue, a.shape, None, a_buf, b_buf, dest_buf)
 
a_plus_b = numpy.empty_like(a)
cl.enqueue_copy(queue, a_plus_b, dest_buf)
 
print la.norm(a_plus_b - (a+b))