Learning NumPy Array

Fancy indexing

Fancy indexing is indexing that does not involve integers or slices, which is normal indexing. In this section, we will apply fancy indexing to set the diagonal values of the Lena image to 0. This will draw black lines along the diagonals, crossing it through, not because there is something wrong with the image, but just as an exercise. Perform the following steps for fancy indexing:

1. Set the values of the first diagonal to 0. To set the diagonal values to 0, we need to define two different ranges for the x and y values as follows:

   lena[range(xmax), range(ymax)] = 0

2. Now, set the values of the other diagonal to 0. To set the values of the other diagonal, we require a different set of ranges, but the principles stay the same, as follows: ...