[FIXED] How to accessing indices in an array at transition in an array from one to another value (python)

Issue

I have an array like:

val=[[1,1,1,0,0,1,1,0,0,0], [0,1,1,1,0,1,1,0,0,0]]

I would like to access the indices where the value changes from 1 to 0.

Expected output is like:

    [[(2,3),(4,5),(6,7)],[(0,1),(3,4),(4,5),(6,7)]]

I tried with np.gradient function, and able to find the gradient value. Instead of this is any better method:

X=np.gradient(val,axis=1)
Y=np.gradient(val,axis=0)
         
trans_YX = np.array(list(zip(Y.ravel(),X.ravel())),dtype('f4,f4')).reshape(Y.shape)

Current output:

[[(-1.,  0. ) ( 0.,  0. ) ( 0., -0.5) ( 1., -0.5) ( 0.,  0.5) ( 0.,  0.5)
  ( 0., -0.5) ( 0., -0.5) ( 0.,  0. ) ( 0.,  0. )]
 [(-1.,  1. ) ( 0.,  0.5) ( 0.,  0. ) ( 1., -0.5) ( 0.,  0. ) ( 0.,  0.5)
  ( 0., -0.5) ( 0., -0.5) ( 0.,  0. ) ( 0.,  0. )]]

Solution

If pure python works for our solution. you can apply the methodology to each row:

[(i, i + 1) for i in range(len((val_row)) - 1) if val_row[i] != val_row[i+1]]

Answered By - Muhammad Ahsan