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# rms() - Signal Processing

### Syntax

### Example

### Output / Return Value

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### Reference

Y = rms(X) returns the root-mean-square (RMS) level of the input, X. If X is a row or column vector, Y is a real-valued scalar. For matrices, Y contains the RMS levels computed along the first nonsingleton dimension. For example, if X is an N-by-M matrix with N > 1, Y is a 1-by-M row vector containing the RMS levels of the columns of X.Y = rms(X,DIM) computes the RMS level of X along the dimension, DIM.

Y = rms(X)Y = rms(X,DIM)

RMS Level of SinusoidOpen This Example Compute the RMS level of a 100 Hz sinusoid sampled at 1 kHz. t = 0:0.001:1-0.001; x = cos(2*pi*100*t); y = rms(x) y = 0.7071 RMS Levels of 2-D MatrixOpen This Example Create a matrix where 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 RMS levels of the columns.t = 0:0.001:1-0.001; x = cos(2*pi*100*t)'*(1:4); y = rms(x) y = 0.7071 1.4142 2.1213 2.8284 RMS Levels of 2-D Matrix Along Specified DimensionOpen This Example Create a matrix where 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 = rms(x,2) y = 0.7071 1.4142 2.1213 2.8284