MATLAB Function Reference    

Sum of array elements



B = sum(A) returns sums along different dimensions of an array.

If A is a vector, sum(A) returns the sum of the elements.

If A is a matrix, sum(A) treats the columns of A as vectors, returning a row vector of the sums of each column.

If A is a multidimensional array, sum(A) treats the values along the first non-singleton dimension as vectors, returning an array of row vectors.

B = sum(A,dim) sums along the dimension of A specified by scalar dim.


sum(diag(X)) is the trace of X.


The magic square of order 3 is

This is called a magic square because the sums of the elements in each column are the same.

as are the sums of the elements in each row, obtained by transposing:

See Also

cumsum, diff, prod, trace

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