Difference between np.dot and np.multiply with np.sum in binary cross-entropy loss calculation

Question

I have tried the following code but didn\'t find the difference between np.dot and np.multiply with np.sum

Here is np.dot

Answer 1

In this example it just not a coincidence. Lets take an example we have two (1,3) and (1,3) matrices. 
// Lets code 

import numpy as np

x1=np.array([1, 2, 3]) // first array
x2=np.array([3, 4, 3]) // second array

//Then 

X_Res=np.sum(np.multiply(x1,x2)) 
// will result 20 as it will be calculated as - (1*3)+(2*4)+(3*3) , i.e element wise
// multiplication followed by sum.

Y_Res=np.dot(x1,x2.T) 

// in order to get (1,1) matrix) from a dot of (1,3) matrix and //(1,3) matrix we need to //transpose second one. 
//Hence|1 2 3| * |3|
//               |4| = |1*3+2*4+3*3| = |20|
//               |3|
// will result 20 as it will be (1*3)+(2*4)+(3*3) , i.e. dot product of two matrices

print X_Res //20

print Y_Res //20