core/org.jetbrains.kotlinx.dataframe.math/quantileIndex

quantileIndex

internal fun <T : Comparable<T & Any>?> Sequence<T>.quantileIndex(p: Double, type: KType, skipNaN: Boolean, method: QuantileEstimationMethod.Selecting, name: String = "quantile"): Int

Returns the index of the p-quantile in the unsorted sequence this, selected using method.

-1 if empty or all null (or all NaN if skipNaN)
index of the first NaN if !skipNaN and this contains NaN
index of the selected value else

NaN values are detected at runtime when type could hold them, including erased types like Comparable<Any>, used by the column: String overloads.