# API Reference


## Main function


Run the high-frequency PCA algorithm


[pca_high_freq()](pca_high_freq.md#hfpca.pca_high_freq)  
Run high-frequency PCA on a data matrix.

[pca_start_evectors()](pca_start_evectors.md#hfpca.pca_start_evectors)  
Calculate the starting eigenvectors for the high-frequency PCA routine.


## Analysis functions


Analyze the results


[plot_loadings()](plot_loadings.md#hfpca.plot_loadings)  
Plot the loading contribution between variables and principal components over time.

[plot_pcs()](plot_pcs.md#hfpca.plot_pcs)  
Plot the principal component trajectories colored by explained variance.

[quantiles_cut()](quantiles_cut.md#hfpca.quantiles_cut)  
Compute the fraction of values above the PCA cutoff per feature.