I am trying to create 3 numpy arrays/lists using data from another array called mean_data as follows:
---> 39 R = np.array(mean_data[:,0]) 40 P = np.
np.append needs the array as the first argument and the list you want to append as the second:
mean_data = np.append(mean_data, [ur, ua, np.mean(data[samepoints,-1])])