Numpy I want to add numbers to my for loops when it reaches row 5-CodePudding

I am trying to add 1,2,3,4,5 after the fourth role which means I want to add numbers starting from row 5 of my 10x10 arrays. Below Attached with my code.

big_arr = np.zeros((10,10),dtype=np.uint8)
count = 0
for x in range(0,10):
    for y in range(0,10):
        if big_arr[x,y] > 50:
            big_arr[x,y] = count   1
            count  = 1

Im not sure why the value of big_arr[x,y] is 0 and if i switch the operator to < it will then add 1 continuously. Aren't the value will be adding after the row and columns reach 50? Thank you

CodePudding user response：

If you're working on numpy, and doing for loops, you're most likely doing something wrong.

The speed of numpy achieved through slicing .

import numpy as np

my_array=np.zeros((10,10))
print(my_array)

#[[0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]
# [0. 0. 0. 0. 0. 0. 0. 0. 0. 0.]]

fill_array = np.arange(1,51).reshape(5,10)
print(fill_array)

#[[ 1  2  3  4  5  6  7  8  9 10]
# [11 12 13 14 15 16 17 18 19 20]
# [21 22 23 24 25 26 27 28 29 30]
# [31 32 33 34 35 36 37 38 39 40]
# [41 42 43 44 45 46 47 48 49 50]]

my_array[5:,:] = fill_array
print(my_array)


#[[ 0.  0.  0.  0.  0.  0.  0.  0.  0.  0.]
# [ 0.  0.  0.  0.  0.  0.  0.  0.  0.  0.]
# [ 0.  0.  0.  0.  0.  0.  0.  0.  0.  0.]
# [ 0.  0.  0.  0.  0.  0.  0.  0.  0.  0.]
# [ 0.  0.  0.  0.  0.  0.  0.  0.  0.  0.]
# [ 1.  2.  3.  4.  5.  6.  7.  8.  9. 10.]
# [11. 12. 13. 14. 15. 16. 17. 18. 19. 20.]
# [21. 22. 23. 24. 25. 26. 27. 28. 29. 30.]
# [31. 32. 33. 34. 35. 36. 37. 38. 39. 40.]
# [41. 42. 43. 44. 45. 46. 47. 48. 49. 50.]]

CodePudding user response：

Hello I just found out the answer.

big_arr = np.zeros((10,10),dtype=np.uint8)
count = 0
for x in range(5,10):
    for y in range(0,10):
        big_arr[x,y] = count   1
        count  = 1

All I did was changing the range in x to 5 and the value starts kicking in. Thank you.