rms — Compute root mean square values.
rms(X) computes sqrt(mean(abs(X).^2)) along the first non-singleton dimension. Dimension, vector-dimension, "all", "includenan", "omitnan", "includemissing", and "omitmissing" forms are supported.
Syntax
Y = rms(X)
Y = rms(X, dim)
Y = rms(X, dim, nanflag)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
X | Any | Yes | — | Input data array. |
dim | Any | No | — | Dimension, dimension vector, or "all" selector. |
options | Any | Variadic | — | Optional dimension and missing-value arguments. |
Returns
| Name | Type | Description |
|---|---|---|
Y | NumericArray | Computed statistic. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:rms:InvalidArgument | Inputs, flags, dimensions, or options are malformed. | descriptive statistics: invalid argument |
RunMat:rms:Internal | Internal tensor conversion or allocation fails. | descriptive statistics: internal error |
How rms works
- NaNs are included by default.
"omitnan"skips NaNs in each slice; empty slices returnNaN.- Logical and integer inputs are promoted to double precision before reduction.
- Complex inputs are reduced using magnitude.
Example
Root mean square of a vector
r = rms([1 2 4], "all")Using rms with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how rms changes the result.
Run a small rms example, explain the result, then change one input and compare the output.
FAQ
Is rms the same as norm divided by sqrt(n)?⌄
For a vector without omitted values, yes: rms(x) equals norm(x)/sqrt(numel(x)).
Related Math functions
Reduction
all · any · bounds · cummax · cummin · cumprod · cumsum · cumtrapz · diff · gradient · max · maxk · mean · median · min · mink · movmax · movmean · movmedian · movmin · movprod · movstd · movsum · movvar · nnz · prod · std · sum · trapz · var
Elementwise
abs · angle · bsxfun · complex · conj · double · erf · erfcinv · exp · expm1 · factorial · flintmax · gamma · gammaln · heaviside · hypot · idivide · imag · intmax · intmin · ldivide · log · log10 · log1p · log2 · minus · nextpow2 · plus · pow2 · power · rdivide · real · realmax · realmin · realsqrt · rescale · sign · single · sqrt · swapbytes · times · uint32
Trigonometry
acos · acosh · asin · asinh · atan · atan2 · atanh · cos · cosd · cosh · cospi · deg2rad · pol2cart · rad2deg · sin · sind · sinh · sinpi · tan · tand · tanh
Structure
bandwidth · isdiag · ishermitian · issymmetric · istril · istriu · symrcm
Signal
blackman · butter · buttord · cheb2ord · conv · conv2 · deconv · downsample · envelope · filter · filtfilt · fir1 · freqz · gauspuls · hamming · hann · hilbert · periodogram · pulstran · pwelch · rectpuls · resample · sawtooth · sinc · spectrogram · square · tripuls · unwrap · upsample · zplane
Optim
coneprog · fminbnd · fminunc · fsolve · fzero · integral · linprog · lsqcurvefit · lsqnonlin · optimset · quad · secondordercone
Ops
cross · ctranspose · dot · mldivide · mpower · mrdivide · mtimes · pagemtimes · pagetranspose · trace · transpose
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how rms is executed, line by line, in Rust.
- View the source for rms in Rust on GitHub
- Learn how the RunMat runtime works
- Found a bug? Open an issue with a minimal reproduction.
About RunMat
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