Removal of 1/(pie^1/2) in dKernel

[Himanshunitrr]

This might be stupid question but why do we not include 1/(pie^1/2) in dKernel? As per my understanding as Gaussians are separable, derivatives of Gaussians are separable, so dKernel are respective zeroth, first and second derivative of Gaussians but I see that for some reason we dont include 1/(pie^1/2) in the prefix (where prefix is the term which we multiply to baseKernel. I am using these features to segment collagen fibres.

https://github.com/GriffinLab/BIFs/blob/b737a5ab3d45c8bde8e52e0ed7c18bb02239a385/Matlab/DtGfiltersBank.m#L18C39-L18C49

baseKernel = exp(-xSquared./(2*sigma^2));
dKernel{1} = (1/(sqrt(2)*sigma)).*baseKernel;
dKernel{2} = -x.*(1/(sqrt(2)*sigma^3)).*baseKernel;
dKernel{3} = (xSquared-sigma^2).*(1/(sqrt(2)*sigma^5)).*baseKernel;

Thanks in advance