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Copy file name to clipboardExpand all lines: lib/node_modules/@stdlib/lapack/base/README.md
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@@ -30,13 +30,13 @@ Many LAPACK routines work with banded matrices, which are stored compactly in tw
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### General Band Matrix Storage
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A general band matrix of size `M`-by-`N` with `KL` subdiagonals and `KU` superdiagonals is stored in a two-dimensional array `AB` with `KL+KU+1` rows and `N` columns.
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A general band matrix of size `M`-by-`N` with `KL` subdiagonals and `KU` superdiagonals is stored in a two-dimensional array `A` with `KL+KU+1` rows and `N` columns.
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**Storage Mapping:**
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- Columns of the original matrix are stored in corresponding columns of the array `AB`.
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- Diagonals of the matrix are stored in rows of the array `AB`.
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- Element `A[i, j]` from the original matrix is stored in `AB[KU+1+i-j, j]`.
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- Columns of the original matrix are stored in corresponding columns of the array `A`.
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- Diagonals of the matrix are stored in rows of the array `A`.
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- Element `A[i, j]` from the original matrix is stored in `A[KU+1+i-j, j]`.
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- Valid range for `i`: `max(1, j-KU) <= i <= min(M, j+KL)`.
`AB` is a 4×5 matrix as `KL+KU+1 = 2+1+1 = 4`. Elements marked `*` need not be set and are not referenced by LAPACK routines.
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`A` is a 4×5 matrix as `KL+KU+1 = 2+1+1 = 4`. Elements marked `*` need not be set and are not referenced by LAPACK routines.
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**Note:** When a band matrix is supplied for LU factorization, space must be allowed to store an additional `KL` superdiagonals, which are generated by fill-in as a result of row interchanges. This means that the matrix is stored according to the above scheme, but with `KL + KU` superdiagonals.
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@@ -93,12 +93,12 @@ For symmetric or Hermitian band matrices with `KD` subdiagonals or superdiagonal
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**Upper Triangle Storage (UPLO = 'U'):**
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- Element `A[i, j]` is stored in `AB[KD+1+i-j, j]`.
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- Element `A[i, j]` is stored in `A[KD+1+i-j, j]`.
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- Valid range for `i`: `max(1, j-KD) <= i <= j`.
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**Lower Triangle Storage (UPLO = 'L'):**
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- Element `A[i, j]` is stored in `AB[1+i-j, j]`.
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- Element `A[i, j]` is stored in `A[1+i-j, j]`.
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- Valid range for `i`: `j <= i <= min(N, j+KD)`.
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#### Example
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<!-- </equation> -->
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the band storage matrix `AB` when `UPLO = 'U'` (i.e., upper triangle) is
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the band storage matrix `A` when `UPLO = 'U'` (i.e., upper triangle) is
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