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 // Copyright ©2015 The Gonum Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package gonum import "gonum.org/v1/gonum/blas" // Dlacpy copies the elements of A specified by uplo into B. Uplo can specify // a triangular portion with blas.Upper or blas.Lower, or can specify all of the // elements with blas.All. // // Dlacpy is an internal routine. It is exported for testing purposes. func (impl Implementation) Dlacpy(uplo blas.Uplo, m, n int, a []float64, lda int, b []float64, ldb int) { switch { case uplo != blas.Upper && uplo != blas.Lower && uplo != blas.All: panic(badUplo) case m < 0: panic(mLT0) case n < 0: panic(nLT0) case lda < max(1, n): panic(badLdA) case ldb < max(1, n): panic(badLdB) } if m == 0 || n == 0 { return } switch { case len(a) < (m-1)*lda+n: panic(shortA) case len(b) < (m-1)*ldb+n: panic(shortB) } switch uplo { case blas.Upper: for i := 0; i < m; i++ { for j := i; j < n; j++ { b[i*ldb+j] = a[i*lda+j] } } case blas.Lower: for i := 0; i < m; i++ { for j := 0; j < min(i+1, n); j++ { b[i*ldb+j] = a[i*lda+j] } } case blas.All: for i := 0; i < m; i++ { for j := 0; j < n; j++ { b[i*ldb+j] = a[i*lda+j] } } } }