FindTransferAnchors: how do column sums of weights matrix all equal 1?

[danielcgingerich]

Hi,

I am just wondering how this was figured out. From anchor weighting I see that:
D = [1 - dist(c, a)/dist(c, a.kweight) ]*anchor.score
gaussian kernal applied to D
D = 1-exp(-D/(2/sd)^2)
and then normalized by all surrounding anchors for the anchor weight.

How is it that the resulting anchors sum to 1?

[timoast]

We make them sum to 1 by dividing by the column sums: https://github.com/satijalab/seurat/blob/master/src/integration.cpp#L80