Spearman correlation of value ranks with chronological order, times 100.
Tied values receive their average rank. A constant or one-value window is
NaN, as is warmup before a full period including the current bar. Missing
values propagate by default; skip ranks the last period finite observations
and holds across gaps. Invalid periods throw RangeError; unknown policies
throw TypeError.
Spearman correlation of value ranks with chronological order, times 100. Tied values receive their average rank. A constant or one-value window is NaN, as is warmup before a full period including the current bar. Missing values propagate by default;
skipranks the last period finite observations and holds across gaps. Invalid periods throw RangeError; unknown policies throw TypeError.