title" content="Plot long-term hydrograph variable changes — gr_plot_periods"><meta property="og:description" content="This function generates boxplots of the hydrograph separation variables produced by gr_summarize(). The data for each variable is divided into two samples: before and after the change year either set by year parameter or extracted from tests (statistically estimated). Different background fill colors are used to differentiate seasons types."><!-- mathjax --><script src="https://cdnjs.clou