How to sum 3D matrix along 2 and 3 dimention

There is 20x10x10 matrix how to sum all elements in the 2D slices along the 20 elements.

The end result should be 20x1 vector

B = ones(20,10,10);

Answer 1

[Stephen23]

B = ones(20,10,10);
V = sum(B,2:3)

V = 20×1

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