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Peak-magnitude-to-RMS ratio



y = peak2rms(x) returns the ratio of the largest absolute value in x to the root-mean-square (RMS) value of x.


y = peak2rms(x,dim) computes the peak-magnitude-to-RMS ratio of x along dimension dim.


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Compute the peak-magnitude-to-RMS ratio of a 100 Hz sinusoid sampled at 1 kHz.

t = 0:0.001:1-0.001;
x = cos(2*pi*100*t);

y = peak2rms(x)
y = 1.4142

Create a complex exponential with a frequency of π/4 rad/sample. Find the peak-magnitude-to-RMS ratio.

n = 0:99;
x = exp(1j*pi/4*n);

y = peak2rms(x)
y = 1

Create a matrix in which each column is a 100 Hz sinusoid sampled at 1 kHz with a different amplitude. The amplitude is equal to the column index.

Compute the peak-magnitude-to-RMS ratios of the columns.

t = 0:0.001:1-0.001;
x = cos(2*pi*100*t)'*(1:4);

y = peak2rms(x)
y = 1×4

    1.4142    1.4142    1.4142    1.4142

Create a matrix in which each row is a 100 Hz sinusoid sampled at 1 kHz with a different amplitude. The amplitude is equal to the row index.

Compute the RMS levels of the rows, specifying the dimension equal to 2 with the dim argument.

t = 0:0.001:1-0.001;
x = (1:4)'*cos(2*pi*100*t);

y = peak2rms(x,2)
y = 4×1


Input Arguments

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Input signal, specified as a vector, matrix, or N-D array.

Data Types: double | single
Complex Number Support: Yes

Dimension to operate along, specified as a positive integer scalar. By default, peak2rms operates along the first array dimension of x with size greater than 1. For example, if x is a row or column vector, y is a real-valued scalar. If x is an N-by-M matrix with N > 1, y is a 1-by-M row vector containing the peak-magnitude-to-RMS levels of the columns of y.

Data Types: double | single

Output Arguments

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Peak-magnitude-to-RMS ratio, specified as a real-valued scalar, matrix, or N-D array.

More About

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Peak-Magnitude-to-RMS Ratio

The peak-magnitude-to-RMS ratio is


where the infinity-norm and RMS values are computed along the specified dimension.


[1] IEEE® Standard on Transitions, Pulses, and Related Waveforms, IEEE Standard 181, 2003.

Extended Capabilities

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

Version History

Introduced in R2012a

See Also

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