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times, .*

Multiplication

Description

example

C = A.*B multiplies arrays A and B by multiplying corresponding elements. The sizes of A and B must be the same or be compatible.

If the sizes of A and B are compatible, then the two arrays implicitly expand to match each other. For example, if one of A or B is a scalar, then the scalar is combined with each element of the other array. Also, vectors with different orientations (one row vector and one column vector) implicitly expand to form a matrix.

C = times(A,B) is an alternate way to execute A.*B, but is rarely used. It enables operator overloading for classes.

Examples

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Create two vectors, A and B, and multiply them element by element.

A = [1 0 3];
B = [2 3 7];
C = A.*B
C = 1×3

     2     0    21

Create two 3-by-3 arrays, A and B, and multiply them element by element.

A = [1 0 3; 5 3 8; 2 4 6];
B = [2 3 7; 9 1 5; 8 8 3];
C = A.*B
C = 3×3

     2     0    21
    45     3    40
    16    32    18

Create a row vector a and a column vector b, then multiply them. The 1-by-3 row vector and 4-by-1 column vector combine to produce a 4-by-3 matrix.

a = 1:3;
b = (1:4)';
a.*b
ans = 4×3

     1     2     3
     2     4     6
     3     6     9
     4     8    12

The result is a 4-by-3 matrix, where each (i,j) element in the matrix is equal to a(j).*b(i):

a=[a1a2a3],b=[b1b2b3b4],          a.*b=[a1b1a2b1a3b1a1b2a2b2a3b2a1b3a2b3a3b3a1b4a2b4a3b4].

Input Arguments

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Operands, specified as scalars, vectors, matrices, or multidimensional arrays. Inputs A and B must either be the same size or have sizes that are compatible (for example, A is an M-by-N matrix and B is a scalar or 1-by-N row vector). For more information, see Compatible Array Sizes for Basic Operations.

  • Operands with an integer data type cannot be complex.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | logical | char | categorical | duration | calendarDuration
Complex Number Support: Yes

Compatibility Considerations

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Behavior changed in R2016b

Behavior changed in R2020b

Extended Capabilities

Introduced before R2006a