A = size 16 by 16 SparseMatrix of double (64 nz):
A(:,j0) = 3 nz [ i0,3 i1,-1 i4,-1 ]
A(:,j1) = 4 nz [ i0,-1 i1,4 i2,-1 i5,-1 ]
A(:,j2) = 4 nz [ i1,-1 i2,4 i3,-1 i6,-1 ]
A(:,j3) = 3 nz [ i2,-1 i3,3 i7,-1 ]
A(:,j4) = 4 nz [ i0,-1 i4,4 i5,-1 i8,-1 ]
A(:,j5) = 5 nz [ i1,-1 i4,-1 i5,5 i6,-1 i9,-1 ]
A(:,j6) = 5 nz [ i2,-1 i5,-1 i6,5 i7,-1 i10,-1 ]
A(:,j7) = 4 nz [ i3,-1 i6,-1 i7,4 i11,-1 ]
A(:,j8) = 4 nz [ i4,-1 i8,4 i9,-1 i12,-1 ]
A(:,j9) = 5 nz [ i5,-1 i8,-1 i9,5 i10,-1 i13,-1 ]
A(:,j10) = 5 nz [ i6,-1 i9,-1 i10,5 i11,-1 i14,-1 ]
A(:,j11) = 4 nz [ i7,-1 i10,-1 i11,4 i15,-1 ]
A(:,j12) = 3 nz [ i8,-1 i12,3 i13,-1 ]
A(:,j13) = 4 nz [ i9,-1 i12,-1 i13,4 i14,-1 ]
A(:,j14) = 4 nz [ i10,-1 i13,-1 i14,4 i15,-1 ]
A(:,j15) = 3 nz [ i11,-1 i14,-1 i15,3 ]

A.pattern() = size 16 by 16 Pattern:
[ x x - - x - - - - - - - - - - - ]
[ x x x - - x - - - - - - - - - - ]
[ - x x x - - x - - - - - - - - - ]
[ - - x x - - - x - - - - - - - - ]
[ x - - - x x - - x - - - - - - - ]
[ - x - - x x x - - x - - - - - - ]
[ - - x - - x x x - - x - - - - - ]
[ - - - x - - x x - - - x - - - - ]
[ - - - - x - - - x x - - x - - - ]
[ - - - - - x - - x x x - - x - - ]
[ - - - - - - x - - x x x - - x - ]
[ - - - - - - - x - - x x - - - x ]
[ - - - - - - - - x - - - x x - - ]
[ - - - - - - - - - x - - x x x - ]
[ - - - - - - - - - - x - - x x x ]
[ - - - - - - - - - - - x - - x x ]

A.left(10) = size 16 by 10 Pattern:
[sliced]
[ x x - - x - - - - - ]
[ x x x - - x - - - - ]
[ - x x x - - x - - - ]
[ - - x x - - - x - - ]
[ x - - - x x - - x - ]
[ - x - - x x x - - x ]
[ - - x - - x x x - - ]
[ - - - x - - x x - - ]
[ - - - - x - - - x x ]
[ - - - - - x - - x x ]
[ - - - - - - x - - x ]
[ - - - - - - - x - - ]
[ - - - - - - - - x - ]
[ - - - - - - - - - x ]
[ - - - - - - - - - - ]
[ - - - - - - - - - - ]

A.top(5) = size 5 by 16 Pattern:
[sliced]
[ x x - - x - - - - - - - - - - - ]
[ x x x - - x - - - - - - - - - - ]
[ - x x x - - x - - - - - - - - - ]
[ - - x x - - - x - - - - - - - - ]
[ x - - - x x - - x - - - - - - - ]

A.bottom(6).right(6) = size 6 by 6 Pattern:
[sliced]
[ x x - - x - ]
[ x x - - - x ]
[ - - x x - - ]
[ - - x x x - ]
[ x - - x x x ]
[ - x - - x x ]

A(3,3) = 0 .. size 16 by 16 SparseMatrix of double (64 nz):
A(:,j0) = 3 nz [ i0,6 i1,-2 i4,-1 ]
A(:,j1) = 4 nz [ i0,-2 i1,8 i2,-1 i5,-1 ]
A(:,j2) = 4 nz [ i1,-2 i2,4 i3,-1 i6,-1 ]
A(:,j3) = 3 nz [ i2,-1 i3,0 i7,-1 ]
A(:,j4) = 4 nz [ i0,-2 i4,4 i5,-1 i8,-1 ]
A(:,j5) = 5 nz [ i1,-2 i4,-1 i5,5 i6,-1 i9,-1 ]
A(:,j6) = 5 nz [ i2,-1 i5,-1 i6,5 i7,-1 i10,-1 ]
A(:,j7) = 4 nz [ i3,-1 i6,-1 i7,4 i11,-1 ]
A(:,j8) = 4 nz [ i4,-1 i8,4 i9,-1 i12,-1 ]
A(:,j9) = 5 nz [ i5,-1 i8,-1 i9,5 i10,-1 i13,-1 ]
A(:,j10) = 5 nz [ i6,-1 i9,-1 i10,5 i11,-1 i14,-1 ]
A(:,j11) = 4 nz [ i7,-1 i10,-1 i11,4 i15,-1 ]
A(:,j12) = 3 nz [ i8,-1 i12,3 i13,-1 ]
A(:,j13) = 4 nz [ i9,-1 i12,-1 i13,4 i14,-1 ]
A(:,j14) = 4 nz [ i10,-1 i13,-1 i14,4 i15,-1 ]
A(:,j15) = 3 nz [ i11,-1 i14,-1 i15,3 ]

A.erase(3,3) .. size 16 by 16 SparseMatrix of double (63 nz):
A(:,j0) = 3 nz [ i0,6 i1,-2 i4,-1 ]
A(:,j1) = 4 nz [ i0,-2 i1,8 i2,-1 i5,-1 ]
A(:,j2) = 4 nz [ i1,-2 i2,4 i3,-1 i6,-1 ]
A(:,j3) = 2 nz [ i2,-1 i7,-1 ]
A(:,j4) = 4 nz [ i0,-2 i4,4 i5,-1 i8,-1 ]
A(:,j5) = 5 nz [ i1,-2 i4,-1 i5,5 i6,-1 i9,-1 ]
A(:,j6) = 5 nz [ i2,-1 i5,-1 i6,5 i7,-1 i10,-1 ]
A(:,j7) = 4 nz [ i3,-1 i6,-1 i7,4 i11,-1 ]
A(:,j8) = 4 nz [ i4,-1 i8,4 i9,-1 i12,-1 ]
A(:,j9) = 5 nz [ i5,-1 i8,-1 i9,5 i10,-1 i13,-1 ]
A(:,j10) = 5 nz [ i6,-1 i9,-1 i10,5 i11,-1 i14,-1 ]
A(:,j11) = 4 nz [ i7,-1 i10,-1 i11,4 i15,-1 ]
A(:,j12) = 3 nz [ i8,-1 i12,3 i13,-1 ]
A(:,j13) = 4 nz [ i9,-1 i12,-1 i13,4 i14,-1 ]
A(:,j14) = 4 nz [ i10,-1 i13,-1 i14,4 i15,-1 ]
A(:,j15) = 3 nz [ i11,-1 i14,-1 i15,3 ]

