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times, .*

Symbolic array multiplication

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Syntax

A.*B
times(A,B)

Description

A.*B performs element-wise multiplication of A and B.

example

times(A,B) is equivalent to A.*B.

Examples

Multiply Matrix by Scalar

Create a 2-by-3 matrix.

A = sym('a', [2 3])
A =
[ a1_1, a1_2, a1_3]
[ a2_1, a2_2, a2_3]

Multiply the matrix by the symbolic expression sin(b). Multiplying a matrix by a scalar means multiplying each element of the matrix by that scalar.

syms b
A.*sin(b)
ans =
[ a1_1*sin(b), a1_2*sin(b), a1_3*sin(b)]
[ a2_1*sin(b), a2_2*sin(b), a2_3*sin(b)]

Multiply Two Matrices

Create a 3-by-3 symbolic Hilbert matrix and a 3-by-3 diagonal matrix.

H = sym(hilb(3))
d = diag(sym([1 2 3]))
H =
[   1, 1/2, 1/3]
[ 1/2, 1/3, 1/4]
[ 1/3, 1/4, 1/5]
 
d =
[ 1, 0, 0]
[ 0, 2, 0]
[ 0, 0, 3]

Multiply the matrices by using the element-wise multiplication operator .*. This operator multiplies each element of the first matrix by the corresponding element of the second matrix. The dimensions of the matrices must be the same.

H.*d
ans =
[ 1,   0,   0]
[ 0, 2/3,   0]
[ 0,   0, 3/5]

Multiply Expression by Symbolic Function

Multiply a symbolic expression by a symbolic function. The result is a symbolic function.

syms f(x)
f(x) = x^2;
f1 = (x^2 + 5*x + 6).*f
f1(x) =
x^2*(x^2 + 5*x + 6)

Input Arguments

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Input, specified as a number, or a symbolic number, scalar variable, matrix variable, function, matrix function, expression, or vector, matrix, or array of symbolic scalar variables. Inputs A and B must be the same size unless one is a scalar. A scalar value expands into an array of the same size as the other input.

Input, specified as a number, or a symbolic number, scalar variable, matrix variable, function, matrix function, expression, or vector, matrix, or array of symbolic scalar variables. Inputs A and B must be the same size unless one is a scalar. A scalar value expands into an array of the same size as the other input.

Version History

Introduced before R2006a

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See Also

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