By Viet Nguyen

I’m totally newbie in Python and i’m trying to create a 1280×720 BOOLEAN matrix which is TRUE when x-index and y-index are satisfied in conditions. Specifically, the black area is where i want all values is TRUE, others is FALSE.

This is the image geometry of the matrix

So far i did a code like this:

```
mask_mat = np.zeros((1280,720),np.bool)
for i in np.arange(640,1220):
for j in np.arange(0,360):
if ((j > (-9/16*i + 690))&(j < (-9/16*i + 750))):
mask_mat[i][j] = True;
```

But the loop take up so much time. So please help!

Source: Stack Overflow