%python from numba import jit from numpy import arange # jit decorator tells Numba to compile this function. # The argument types will be inferred by Numba when function is called. @jit def sum2d(arr): M, N = arr.shape result = 0.0 for i in range(M): for j in range(N): result += arr[i,j] return result a = arange(9).reshape(3,3) print(sum2d(a))

36.0