typo

Author: Jonathan Rocher

py_open_cl_demo.py

@@ -19,7 +19,7 @@
 # Just in Time compiler. 
 # Notice the way we index into the array a: get_global_id
 prg = cl.Program(ctx, """
-    __kernel void twice(_global float *a)
+    __kernel void twice(__global float *a)
     { a[ get_global_id (0)] *= 2;}
     """).build()