Hi all,

I have ran my code to simulate cell growth diffusing a cross a thin rectangular domain of length 0.6 with a initial condition of c = exp(-75 x) over time t = 9.8. This seems to work perfectly fine. but when I scale the model down to a domain length 0.06, t = 0.98 and c = exp(-750 x), I get errors saying there is a singular matrix.

dt was also scaled from dt = 0.002 to dt = 0.0002

does anyone know why this might be and how to fix it?

thanks