tcdf — Evaluate the Student's t cumulative distribution function.
tcdf(x,nu) evaluates the Student's t cumulative distribution function. tcdf(x,nu,"upper") returns the complementary upper-tail probability.
Syntax
p = tcdf(x, nu)
p = tcdf(x, nu, "upper")Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
x | Any | Yes | — | Evaluation point. |
nu | Any | Yes | — | Degrees of freedom parameter. |
Returns
| Name | Type | Description |
|---|---|---|
y | NumericArray | Distribution function value. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:tcdf:InvalidArgument | Inputs are nonnumeric, sizes are incompatible, or too many arguments are supplied. | normal distribution: invalid argument |
RunMat:tcdf:Internal | Internal tensor conversion or allocation fails. | normal distribution: internal error |
How tcdf works
xandnumay be scalars or compatible-size single- or double-precision arrays.- Scalar inputs broadcast over matching-size array inputs.
- Single-precision input produces single-precision output; otherwise the result is double precision.
- In RunMat mode, typed-integer and logical inputs are available as extensions. Integer values must be exactly representable as double before evaluation.
- Nonpositive or
NaNdegrees of freedom produceNaNelementwise. nu = Infuses the standard normal distribution.
Examples
Distribution midpoint
p = tcdf(0, 10)Upper tail
p = tcdf(10, 99, "upper")Using tcdf with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how tcdf changes the result.
Run a small tcdf example, explain the result, then change one input and compare the output.
FAQ
Does tcdf support upper-tail probabilities?⌄
Yes. Pass "upper" as the final argument to compute the complementary tail.
Can I use integer arrays with tcdf?⌄
RunMat mode accepts all eight integer classes when every value is exactly representable as double. MATLAB-compatible mode accepts the documented single- and double-precision forms.
What happens to a GPU result when RunMat uses a host fallback?⌄
The result is copied back to the exact provider that owns the input, with single or double precision preserved.
Related Stats functions
Summary
binocdf · boxplot · cdf · cdfplot · chi2cdf · corr · corrcoef · corrcov · cov · cov2corr · dummyvar · ecdf · filloutliers · fitdist · geomean · grpstats · harmmean · icdf · isoutlier · kstest · kurtosis · lsline · mad · mode · nanmax · normalize · normcdf · norminv · normpdf · onehotdecode · onehotencode · pdf · prctile · quantile · refline · rmse · skewness · tabulate · tiedrank · tinv · tpdf · ttest2 · wblinv
Ml
bayesopt · classify · confusionmat · crossvalind · cvpartition · fitclinear · fitctree · fitlm · kmeans · knnsearch · lasso · lassoglm · linkage · lscov · mnrfit · optimizableVariable · pdist · pdist2 · perfcurve · predict · regress · ridge · squareform · test · training · tsne
Random
binornd · bootstrp · datasample · dividerand · exprnd · gamrnd · lhsdesign · mvnrnd · normrnd · random · randsample · rng · trnd · unidrnd · unifrnd · wblrnd
Hist
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how tcdf is executed, line by line, in Rust.
- View the source for tcdf 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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