import the data, converting to real numbers:
data=N@Import["~/Scratch/optdigits.tes"];
some of these variables are all zeros, for some reason:
zerocolumns=Position[Variance[data],0.]
{{1},{33},{40}}
remove them:
data=Delete[zerocolumns]/@data;
compute the correlations matrix
set those correlations less than 0.35 in magnitude to 0, others to 1.
rtrunc=UnitStep[Abs[r]-0.35];MatrixPlot[rtrunc,ImageSizeSmall]
gtrunc=AdjacencyGraph[rtrunc]
CommunityGraphPlot[gtrunc]
