Band

Band[{i,j}] represents the sequence of positions on the diagonal band that starts with {i,j} in a sparse array.

Band[{imin,jmin,…},{imax,jmax,…}] represents the positions between {imin,jmin,…} and {imax,jmax,…}.

Band[{imin,jmin,…},{imax,jmax,…},{di,dj,…}] represents positions starting with {imin,jmin,…} and then moving with step {di,dj,…}.

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