github.com/jingcheng-WU/gonum@v0.9.1-0.20210323123734-f1a2a11a8f7b/blas/blas64/conv_symmetric.go (about)

     1  // Copyright ©2015 The Gonum Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package blas64
     6  
     7  import "github.com/jingcheng-WU/gonum/blas"
     8  
     9  // SymmetricCols represents a matrix using the conventional column-major storage scheme.
    10  type SymmetricCols Symmetric
    11  
    12  // From fills the receiver with elements from a. The receiver
    13  // must have the same dimensions and uplo as a and have adequate
    14  // backing data storage.
    15  func (t SymmetricCols) From(a Symmetric) {
    16  	if t.N != a.N {
    17  		panic("blas64: mismatched dimension")
    18  	}
    19  	if t.Uplo != a.Uplo {
    20  		panic("blas64: mismatched BLAS uplo")
    21  	}
    22  	switch a.Uplo {
    23  	default:
    24  		panic("blas64: bad BLAS uplo")
    25  	case blas.Upper:
    26  		for i := 0; i < a.N; i++ {
    27  			for j := i; j < a.N; j++ {
    28  				t.Data[i+j*t.Stride] = a.Data[i*a.Stride+j]
    29  			}
    30  		}
    31  	case blas.Lower:
    32  		for i := 0; i < a.N; i++ {
    33  			for j := 0; j <= i; j++ {
    34  				t.Data[i+j*t.Stride] = a.Data[i*a.Stride+j]
    35  			}
    36  		}
    37  	}
    38  }
    39  
    40  // From fills the receiver with elements from a. The receiver
    41  // must have the same dimensions and uplo as a and have adequate
    42  // backing data storage.
    43  func (t Symmetric) From(a SymmetricCols) {
    44  	if t.N != a.N {
    45  		panic("blas64: mismatched dimension")
    46  	}
    47  	if t.Uplo != a.Uplo {
    48  		panic("blas64: mismatched BLAS uplo")
    49  	}
    50  	switch a.Uplo {
    51  	default:
    52  		panic("blas64: bad BLAS uplo")
    53  	case blas.Upper:
    54  		for i := 0; i < a.N; i++ {
    55  			for j := i; j < a.N; j++ {
    56  				t.Data[i*t.Stride+j] = a.Data[i+j*a.Stride]
    57  			}
    58  		}
    59  	case blas.Lower:
    60  		for i := 0; i < a.N; i++ {
    61  			for j := 0; j <= i; j++ {
    62  				t.Data[i*t.Stride+j] = a.Data[i+j*a.Stride]
    63  			}
    64  		}
    65  	}
    66  }
    67  
    68  // SymmetricBandCols represents a symmetric matrix using the band column-major storage scheme.
    69  type SymmetricBandCols SymmetricBand
    70  
    71  // From fills the receiver with elements from a. The receiver
    72  // must have the same dimensions, bandwidth and uplo as a and
    73  // have adequate backing data storage.
    74  func (t SymmetricBandCols) From(a SymmetricBand) {
    75  	if t.N != a.N {
    76  		panic("blas64: mismatched dimension")
    77  	}
    78  	if t.K != a.K {
    79  		panic("blas64: mismatched bandwidth")
    80  	}
    81  	if a.Stride < a.K+1 {
    82  		panic("blas64: short stride for source")
    83  	}
    84  	if t.Stride < t.K+1 {
    85  		panic("blas64: short stride for destination")
    86  	}
    87  	if t.Uplo != a.Uplo {
    88  		panic("blas64: mismatched BLAS uplo")
    89  	}
    90  	dst := BandCols{
    91  		Rows: t.N, Cols: t.N,
    92  		Stride: t.Stride,
    93  		Data:   t.Data,
    94  	}
    95  	src := Band{
    96  		Rows: a.N, Cols: a.N,
    97  		Stride: a.Stride,
    98  		Data:   a.Data,
    99  	}
   100  	switch a.Uplo {
   101  	default:
   102  		panic("blas64: bad BLAS uplo")
   103  	case blas.Upper:
   104  		dst.KU = t.K
   105  		src.KU = a.K
   106  	case blas.Lower:
   107  		dst.KL = t.K
   108  		src.KL = a.K
   109  	}
   110  	dst.From(src)
   111  }
   112  
   113  // From fills the receiver with elements from a. The receiver
   114  // must have the same dimensions, bandwidth and uplo as a and
   115  // have adequate backing data storage.
   116  func (t SymmetricBand) From(a SymmetricBandCols) {
   117  	if t.N != a.N {
   118  		panic("blas64: mismatched dimension")
   119  	}
   120  	if t.K != a.K {
   121  		panic("blas64: mismatched bandwidth")
   122  	}
   123  	if a.Stride < a.K+1 {
   124  		panic("blas64: short stride for source")
   125  	}
   126  	if t.Stride < t.K+1 {
   127  		panic("blas64: short stride for destination")
   128  	}
   129  	if t.Uplo != a.Uplo {
   130  		panic("blas64: mismatched BLAS uplo")
   131  	}
   132  	dst := Band{
   133  		Rows: t.N, Cols: t.N,
   134  		Stride: t.Stride,
   135  		Data:   t.Data,
   136  	}
   137  	src := BandCols{
   138  		Rows: a.N, Cols: a.N,
   139  		Stride: a.Stride,
   140  		Data:   a.Data,
   141  	}
   142  	switch a.Uplo {
   143  	default:
   144  		panic("blas64: bad BLAS uplo")
   145  	case blas.Upper:
   146  		dst.KU = t.K
   147  		src.KU = a.K
   148  	case blas.Lower:
   149  		dst.KL = t.K
   150  		src.KL = a.K
   151  	}
   152  	dst.From(src)
   153  }