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downsample

Decrease sampling rate by integer factor

Syntax

y = downsample(x,n)
y = downsample(x,n,phase)

Description

y = downsample(x,n) decreases the sampling rate of x by keeping every nth sample starting with the first sample. x can be a vector or a matrix. If x is a matrix, each column is considered a separate sequence.

y = downsample(x,n,phase) specifies the number of samples by which to offset the downsampled sequence. phase must be an integer from 0 to n – 1.

Examples

collapse all

Decrease the sampling rate of a sequence by 3.

x = [1 2 3 4 5 6 7 8 9 10];
y = downsample(x,3)
y = 

     1     4     7    10

Decrease the sampling rate of the sequence by 3 and add a phase offset of 2.

y = downsample(x,3,2)
y = 

     3     6     9

Decrease the sampling rate of a matrix by 3.

x = [1  2  3;
     4  5  6;
     7  8  9;
    10 11 12];
y = downsample(x,3)
y = 

     1     2     3
    10    11    12

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Introduced before R2006a

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