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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/lapack"
// Implementation is the native Go implementation of LAPACK routines. It
// is built on top of calls to the return of blas64.Implementation(), so while
// this code is in pure Go, the underlying BLAS implementation may not be.
type Implementation struct{}
var _ lapack.Float64 = Implementation{}
func min(a, b int) int {
if a < b {
return a
}
return b
}
func max(a, b int) int {
if a > b {
return a
}
return b
}
func abs(a int) int {
if a < 0 {
return -a
}
return a
}
const (
// dlamchE is the machine epsilon. For IEEE this is 2^{-53}.
dlamchE = 0x1p-53
// dlamchB is the radix of the machine (the base of the number system).
dlamchB = 2
// dlamchP is base * eps.
dlamchP = dlamchB * dlamchE
// dlamchS is the "safe minimum", that is, the lowest number such that
// 1/dlamchS does not overflow, or also the smallest normal number.
// For IEEE this is 2^{-1022}.
dlamchS = 0x1p-1022
)