How To Save Subarray In Npy File?

My data tracks has following shape : (13044,) Its data types are tracks.dtype.names ('frame_num','mean_x','mean_y','var_x','var_y', 'length', 'scale', 'x_pos','y_pos', 't_pos',

Solution 1:

You can save a numpy array of all of your (16,2) y's:

ys = []
for i in range(len(tracks)):
    y=tracks['coords'][i]
    ys.append(y)
    print(y)
np.save('test.npy',np.array(ys))

Also note that you are traversing along tracks with i, but reading tracks['coord'][i] each time (could be different lengths). In addition, if not all y's are in the same length than it would be a problem to create a numpy array out of them, but you can still save a list through np.save and when loading them use np.load('test.npy').item() (again, if you're not saving them as np.array).