Numpy > Masked array > マスクされた箇所に別のarrayの要素を入れる

import numpy as np
import numpy.ma as ma

# checked with PEP8

MASKED_VALUE = -32768
SIZE_X = 3
SIZE_Y = 3

# 1. data preparation
ncep = np.array([[3, 1, 4], [1, 5, 9], [2, 6, 5]])
oisst_unmask = np.array([[2, 7, 1], [8, 2, 8], [1, 8, 2]])
masks = np.array([[1, 0, 1], [1, 0, 1], [1, 0, 1]])
oisst_masked = ma.masked_where(masks, oisst_unmask)
ma.set_fill_value(oisst_masked, MASKED_VALUE)
print(ncep)
print(oisst_unmask)
print(oisst_masked)

# masked.mask = ma.nomask  # unmask > values before masking
print(oisst_masked.mask)

# 2. unmasking by overwriting with ncep data
# flatten_mask = ma.MaskedArray.flatten(oisst_masked)
flatten_mask = oisst_masked.mask.flatten()
flatten_oisst = oisst_masked.flatten()
flatten_ncep = ncep.flatten()
print(flatten_mask)
for idx, elem in enumerate(flatten_oisst):
    if flatten_mask[idx]:
        flatten_oisst[idx] = flatten_ncep[idx]

print(flatten_oisst)
array_oisst = flatten_oisst.reshape([SIZE_X, SIZE_Y])
print(array_oisst)

[[3 1 4]
 [1 5 9]
 [2 6 5]]
[[2 7 1]
 [8 2 8]
 [1 8 2]]
[[-- 7 --]
 [-- 2 --]
 [-- 8 --]]
[[ True False  True]
 [ True False  True]
 [ True False  True]]
[ True False  True  True False  True  True False  True]
[3 7 4 1 2 9 2 8 5]
[[3 7 4]
 [1 2 9]
 [2 8 5]]