[#BloombergLP-bdlsta-LineFit-variance] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlsta.adoc[bdlsta]::xref:BloombergLP/bdlsta/LineFit.adoc[LineFit]::variance :relfileprefix: ../../../ :mrdocs: Return the variance of the data set X's. The behavior is undefined unless `2 <= count`. == Synopsis Declared in `<bdlsta_linefit.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- double variance() const; ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#