onehotdecode — Decode one-hot vectors into class labels.
onehotdecode(B,classes,featureDim) chooses the maximum value along featureDim and maps the index to classes.
Syntax
A = onehotdecode(B, classes, featureDim)
A = onehotdecode(B, classes, featureDim, typename)
A = onehotdecode(B, classes, featureDim, Name, Value)Inputs
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
B | Any | Yes | — | One-hot encoded data. |
classes | Any | Yes | — | Class names corresponding to the one-hot feature dimension. |
featureDim | IntegerScalar | Yes | — | Dimension containing or receiving one-hot feature vectors. |
typename | StringScalar | No | — | Requested output type. |
options | Any | Variadic | — | Name-value options such as ClassNames or OutputType. |
Returns
| Name | Type | Description |
|---|---|---|
A | Any | Decoded labels. |
Errors
| Identifier | When | Message |
|---|---|---|
RunMat:onehotdecode:InvalidArgument | Inputs, dimensions, classes, output types, or options are malformed. | encoding: invalid argument |
RunMat:onehotdecode:Internal | Internal conversion or allocation fails. | encoding: internal error |
How onehotdecode works
- The length of
classesmust match the size ofBalongfeatureDim. - The documented encoded array
Baccepts single or double values in[0,1]; a checked integer or logical zero-one array is a declared RunMat extension. - Ties are resolved by the first class along
featureDim, matching MATLAB-style first-maximum behavior. - The decoded output keeps the encoded shape with the feature dimension set to 1.
- By default the decoded output is categorical and preserves the supplied class order as the category order.
- A positional typename can request
double,single, any of the eight integer classes,string, orcategorical. Logical and cell-string output are declared RunMat extensions, as areOutputTypeandTypenamename-value aliases. - Numeric classes retain exact native values through class selection and requested native output conversion, including adjacent 64-bit labels above
flintmax.
Example
Decode logical one-hot rows
A = onehotdecode(logical([0 1; 1 0]), ["blue" "red"], 2, 'string')Expected output:
A is a 2-by-1 string array.Using onehotdecode with coding agents
Open a RunMat example with live inputs, then ask the agent to explain how onehotdecode changes the result.
Run a small onehotdecode example, explain the result, then change one input and compare the output.
FAQ
What happens when a vector contains all zeros?⌄
The first class is selected because all classes tie at zero.
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 · onehotencode · pdf · prctile · quantile · refline · rmse · skewness · tabulate · tcdf · 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 onehotdecode is executed, line by line, in Rust.
- View the source for onehotdecode 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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