#### Exercise 4

Resume the **previous exercise **(Exercise3) __without using__ the **trace()** method.

#### Solution

`import numpy as np`

def matrix_trace(A):

n = len(A)

# initialization of trace of A

trace = 0

for i in range(0, n):

#trace = trace + aii

trace = trace + A[i][i]

return trace

#Example

A = np.array([[1, 3, 4],

[1, 3, 5],

[3, 2, 2]])

print("Tr(A) = ", matrix_trace(A)) # output: Tr(A) = 6

**Younes Derfoufi**

my-courses.net

my-courses.net