construct a band Matrix
BandMatrix(L, n, options)
list of lists of scalars or list of scalars or Vector of scalars; diagonals of the band Matrix
(optional) non-negative integer; the number of subdiagonals
(optional) parameters; for a complete list, see LinearAlgebra[BandMatrix]
The BandMatrix(L) command constructs a band Matrix from the data provided by L.
If L is a list of lists, then each list element in L is used to initialize a diagonal. The n+1st element of L is placed along the main diagonal. (If L has fewer than n+1 elements, it is automatically extended by 's.) The other diagonals are placed in relation to it: Ln−j+1 is placed in the jth subdiagonal for j=1..n and Ln+k+1 is placed in the kth superdiagonal for k=1..nops⁡L−n−1. If any list element is shorter than the length of the diagonal where it is placed, the remaining entries are filled with 0.
If n is omitted in the calling sequence, BandMatrix attempts to place an equal number of sub- and super-diagonals into the resulting Matrix by using n=iquo⁡nops⁡L,2 subdiagonals.
If L is a list or Vector of scalars, its elements are used to initialize all the entries of the corresponding diagonals. In this case, parameter n must be specified in the calling sequence. If the row dimension r is not specified, it defaults to n+1. If the column dimension is not specified, it defaults to the row dimension. The jth subdiagonal is filled with L[n-j+1] for j = 1 .. n. (If L has fewer than n+1 elements, it is automatically 0-extended.) The main diagonal is filled with L[n + 1]. The kth superdiagonal is filled with L[n + k + 1] for k = 1 .. nops(L)- n - 1.
LL ≔ w,w,x,x,x,y,y,y,z,z:
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