# Reference: isSemimagicSquare

isSemimagicSquare(M), where M is a real matrix, returns true if and only if M is a semi-magic square, i.e. a N×N matrix such that the sum of all elements in every row and column equals the same number, the so-called "magic number" of the semi-magic square. The diagonals need not sum up to the magic number (if they do, the square is also a magic square). See also isNormalSemimagicSquare, isMagicSquare, and isNormalMagicSquare.