1 | ! |
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2 | ! subroutines for PCG or SOR solvers |
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3 | ! (used if the ISML library is not available) |
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4 | ! |
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5 | ! linrg |
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6 | ! gauss |
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7 | ! vmov |
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8 | ! desremopt |
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9 | ! dtrsv |
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10 | ! dger |
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11 | ! xerbla |
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12 | ! lsame |
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13 | ! folr (empty) |
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14 | ! |
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15 | !!---------------------------------------------------------------------- |
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16 | !! OPA 9.0 , LOCEAN-IPSL (2005) |
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17 | !! $Id$ |
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18 | !! This software is governed by the CeCILL licence see modipsl/doc/NEMO_CeCILL.txt |
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19 | !!---------------------------------------------------------------------- |
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20 | SUBROUTINE linrg(kn,pa,klda,painv,kldainv) |
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21 | |
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22 | !! compute inverse matrix |
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23 | |
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24 | IMPLICIT NONE |
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25 | INTEGER kn,klda,kldainv |
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26 | REAL (kind=8) :: pa(kn,kn),painv(kn,kn) |
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27 | REAL (kind=8) :: zb(kn,kn) |
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28 | REAL (kind=8) :: zv(kn) |
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29 | INTEGER iplin(kn) |
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30 | INTEGER ji |
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31 | |
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32 | IF( kn /= klda .OR. kn /= kldainv ) THEN |
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33 | write(0,*)'change your parameters' |
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34 | STOP |
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35 | ENDIF |
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36 | |
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37 | CALL vmov( kn*kn, pa, painv ) |
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38 | |
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39 | CALL gauss( kn, painv, iplin, zv ) |
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40 | |
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41 | zb(:,:) = 0.e0 |
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42 | DO ji = 1, kn |
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43 | zb(ji,ji) = 1.e0 |
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44 | CALL desremopt( kn, painv, iplin, zb(1,ji), zb(1,ji), zv ) |
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45 | END DO |
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46 | CALL vmov( kn*kn, zb, painv ) |
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47 | |
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48 | END SUBROUTINE linrg |
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49 | !--------------------------------------------------------- |
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50 | SUBROUTINE gauss(kn,pa,kplin,pv) |
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51 | |
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52 | IMPLICIT NONE |
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53 | INTEGER kn |
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54 | INTEGER ji,jj,jk |
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55 | INTEGER ik,ipp |
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56 | REAL (kind=8) :: pa(kn,kn),pv(kn) |
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57 | !! REAL (kind=8) :: zpivmax,zalpha |
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58 | REAL (kind=8) :: zalpha |
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59 | INTEGER kplin(kn) |
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60 | INTEGER isamax |
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61 | EXTERNAL isamax |
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62 | |
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63 | ! factorisation de Gauss de la matrice a avec pivot partiel . |
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64 | ! initialisation des pointeurs . |
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65 | DO ji=1,kn |
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66 | kplin(ji)=ji |
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67 | END DO |
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68 | DO jk=1,kn-1 |
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69 | ! recherche du pivot maximal . |
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70 | !! ik=jk |
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71 | !! zpivmax=dabs(pa(jk,jk)) |
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72 | !! DO ji=jk,kn |
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73 | !! IF(dabs(pa(ji,jk)) > zpivmax) THEN |
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74 | !! zpivmax=dabs(pa(ji,jk)) |
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75 | !! ik=ji |
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76 | !! ENDIF |
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77 | !! END DO |
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78 | ik=isamax( kn-jk+1, pa(jk,jk) )+jk-1 |
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79 | ! permutation de la ligne jk et de la ligne ik . |
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80 | IF(jk == 58) THEN |
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81 | PRINT *,'matrix ',(pa(jk,ji),ji=1,kn) |
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82 | PRINT *,' pivot ',ik,kplin(ik),kplin(jk) |
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83 | ENDIF |
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84 | ipp=kplin(ik) |
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85 | kplin(ik)=kplin(jk) |
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86 | kplin(jk)=ipp |
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87 | DO jj=1,kn |
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88 | pv(jj)=pa(ik,jj) |
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89 | pa(ik,jj)=pa(jk,jj) |
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90 | pa(jk,jj)=pv(jj) |
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91 | END DO |
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92 | IF(jk == 58) THEN |
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93 | PRINT *,'matrix ',(pa(jk,ji),ji=1,kn) |
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94 | PRINT *,' pivot ',ik,kplin(ik),kplin(jk) |
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95 | ENDIF |
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96 | ! calcul des coefficients de la colonne k ligne a ligne . |
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97 | DO ji=jk+1,kn |
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98 | IF(pa(jk,jk) == 0) THEN |
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99 | PRINT *,'probleme diagonale nulle',jk,pa(jk,jk) |
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100 | pa(ji,jk)=pa(ji,jk)/1.E-20 |
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101 | ENDIF |
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102 | IF(pa(jk,jk) /= 0) pa(ji,jk)=pa(ji,jk)/pa(jk,jk) |
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103 | END DO |
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104 | !! DO ji=jk+1,kn |
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105 | !! DO jj=jk+1,kn |
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106 | !! pa(ji,jj)=pa(ji,jj)-pa(ji,jk)*pa(jk,jj) |
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107 | !! END DO |
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108 | !! END DO |
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109 | zalpha=-1. |
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110 | CALL dger(kn-jk,kn-jk,zalpha,pa(jk+1,jk),1,pa(jk,jk+1),kn, & |
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111 | pa(jk+1,jk+1),kn) |
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112 | END DO |
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113 | |
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114 | END SUBROUTINE gauss |
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115 | !--------------------------------------------------------- |
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116 | FUNCTION isamax( I, X ) |
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117 | DIMENSION X(I) |
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118 | ISAMAX = 0 |
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119 | XMIN = -1e+50 |
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120 | DO N = 1, I |
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121 | IF(ABS(X(N)) > XMIN ) THEN |
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122 | XMIN = X(N) |
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123 | ISAMAX = N |
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124 | ENDIF |
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125 | END DO |
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126 | END FUNCTION isamax |
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127 | !--------------------------------------------------------- |
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128 | SUBROUTINE vmov(kn,px,py) |
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129 | |
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130 | IMPLICIT NONE |
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131 | INTEGER kn |
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132 | REAL (kind=8) :: px(kn),py(kn) |
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133 | INTEGER ji |
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134 | |
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135 | DO ji=1,kn |
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136 | py(ji)=px(ji) |
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137 | END DO |
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138 | |
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139 | END SUBROUTINE vmov |
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140 | !--------------------------------------------------------- |
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141 | subroutine desremopt(n,a,plin,y,x,v) |
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142 | implicit none |
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143 | integer n,i, j0 |
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144 | !! integer n,i,j,j0 |
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145 | real (kind=8) :: a(n,n),x(n),y(n),v(n) |
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146 | integer plin(n) |
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147 | ! descente remontee du systeme . |
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148 | ! initialisation du vecteur resultat . |
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149 | ! prise en compte de la permutation des lignes . |
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150 | do i=1,n |
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151 | v(i)=y(plin(i)) |
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152 | end do |
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153 | do i=1,n |
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154 | if(v(i) /= 0.) then |
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155 | j0=i-1 |
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156 | goto 1 |
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157 | endif |
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158 | end do |
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159 | 1 continue |
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160 | ! descente du systeme L v = v , L est a diagonale unitaire . |
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161 | !! do j=j0+1,n |
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162 | !! do i=j+1,n |
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163 | !! v(i)=v(i)-a(i,j)*v(j) |
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164 | !! end do |
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165 | !! end do |
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166 | call dtrsv('L','N','U',n-j0,a(j0+1,j0+1),n,v(j0+1),1) |
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167 | ! remontee du systeme U v = v . |
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168 | !! do j=n,1,-1 |
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169 | !! v(j)=v(j)/a(j,j) |
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170 | !! do i=1,j-1 |
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171 | !! v(i)=v(i)-a(i,j)*v(j) |
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172 | !! end do |
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173 | !! end do |
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174 | call dtrsv('U','N','N',n,a,n,v,1) |
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175 | ! prise en compte de la permutation des colonnes . |
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176 | do i=1,n |
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177 | x(i)=v(i) |
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178 | end do |
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179 | |
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180 | end SUBROUTINE desremopt |
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181 | !--------------------------------------------------------- |
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182 | SUBROUTINE DTRSV ( UPLO, TRANS, DIAG, N, A, LDA, X, INCX ) |
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183 | !! .. Scalar Arguments .. |
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184 | INTEGER INCX, LDA, N |
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185 | CHARACTER (len=1) :: DIAG, TRANS, UPLO |
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186 | !! .. Array Arguments .. |
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187 | ! DOUBLE PRECISION A( LDA, * ), X( * ) |
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188 | REAL (kind=8) :: A( LDA, * ), X( * ) |
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189 | !! .. |
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190 | |
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191 | !! Purpose |
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192 | !! ======= |
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193 | |
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194 | !! DTRSV solves one of the systems of equations |
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195 | |
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196 | !! A*x = b, or A'*x = b, |
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197 | |
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198 | !! where b and x are n element vectors and A is an n by n unit, or |
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199 | !! non-unit, upper or lower triangular matrix. |
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200 | |
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201 | !! No test for singularity or near-singularity is included in this |
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202 | !! routine. Such tests must be performed before calling this routine. |
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203 | |
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204 | !! Parameters |
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205 | !! ========== |
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206 | |
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207 | !! UPLO - CHARACTER*1. |
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208 | !! On entry, UPLO specifies whether the matrix is an upper or |
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209 | !! lower triangular matrix as follows: |
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210 | |
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211 | !! UPLO = 'U' or 'u' A is an upper triangular matrix. |
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212 | |
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213 | !! UPLO = 'L' or 'l' A is a lower triangular matrix. |
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214 | |
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215 | !! Unchanged on exit. |
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216 | |
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217 | !! TRANS - CHARACTER*1. |
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218 | !! On entry, TRANS specifies the equations to be solved as |
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219 | !! follows: |
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220 | |
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221 | !! TRANS = 'N' or 'n' A*x = b. |
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222 | |
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223 | !! TRANS = 'T' or 't' A'*x = b. |
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224 | |
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225 | !! TRANS = 'C' or 'c' A'*x = b. |
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226 | |
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227 | !! Unchanged on exit. |
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228 | |
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229 | !! DIAG - CHARACTER*1. |
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230 | !! On entry, DIAG specifies whether or not A is unit |
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231 | !! triangular as follows: |
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232 | |
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233 | !! DIAG = 'U' or 'u' A is assumed to be unit triangular. |
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234 | |
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235 | !! DIAG = 'N' or 'n' A is not assumed to be unit |
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236 | !! triangular. |
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237 | |
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238 | !! Unchanged on exit. |
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239 | |
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240 | !! N - INTEGER. |
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241 | !! On entry, N specifies the order of the matrix A. |
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242 | !! N must be at least zero. |
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243 | !! Unchanged on exit. |
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244 | |
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245 | !! A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). |
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246 | !! Before entry with UPLO = 'U' or 'u', the leading n by n |
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247 | !! upper triangular part of the array A must contain the upper |
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248 | !! triangular matrix and the strictly lower triangular part of |
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249 | !! A is not referenced. |
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250 | !! Before entry with UPLO = 'L' or 'l', the leading n by n |
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251 | !! lower triangular part of the array A must contain the lower |
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252 | !! triangular matrix and the strictly upper triangular part of |
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253 | !! A is not referenced. |
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254 | !! Note that when DIAG = 'U' or 'u', the diagonal elements of |
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255 | !! A are not referenced either, but are assumed to be unity. |
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256 | !! Unchanged on exit. |
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257 | |
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258 | !! LDA - INTEGER. |
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259 | !! On entry, LDA specifies the first dimension of A as declared |
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260 | !! in the calling (sub) program. LDA must be at least |
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261 | !! max( 1, n ). |
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262 | !! Unchanged on exit. |
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263 | |
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264 | !! X - DOUBLE PRECISION array of dimension at least |
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265 | !! ( 1 + ( n - 1 )*abs( INCX ) ). |
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266 | !! Before entry, the incremented array X must contain the n |
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267 | !! element right-hand side vector b. On exit, X is overwritten |
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268 | !! with the solution vector x. |
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269 | |
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270 | !! INCX - INTEGER. |
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271 | !! On entry, INCX specifies the increment for the elements of |
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272 | !! X. INCX must not be zero. |
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273 | !! Unchanged on exit. |
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274 | |
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275 | |
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276 | !! Level 2 Blas routine. |
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277 | |
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278 | !! -- Written on 22-October-1986. |
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279 | !! Jack Dongarra, Argonne National Lab. |
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280 | !! Jeremy Du Croz, Nag Central Office. |
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281 | !! Sven Hammarling, Nag Central Office. |
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282 | !! Richard Hanson, Sandia National Labs. |
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283 | |
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284 | |
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285 | !! .. Parameters .. |
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286 | ! DOUBLE PRECISION ZERO |
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287 | ! PARAMETER ( ZERO = 0.0D+0 ) |
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288 | REAL (kind=8) :: ZERO |
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289 | PARAMETER ( ZERO = 0.0 ) |
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290 | !! .. Local Scalars .. |
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291 | ! DOUBLE PRECISION TEMP |
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292 | REAL (kind=8) :: TEMP |
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293 | INTEGER I, INFO, IX, J, JX, KX |
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294 | LOGICAL NOUNIT |
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295 | !! .. External Functions .. |
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296 | LOGICAL LSAME |
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297 | EXTERNAL LSAME |
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298 | !! .. External Subroutines .. |
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299 | EXTERNAL XERBLA |
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300 | !! .. Intrinsic Functions .. |
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301 | INTRINSIC MAX |
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302 | !! .. |
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303 | !! .. Executable Statements .. |
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304 | |
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305 | !! Test the input parameters. |
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306 | |
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307 | INFO = 0 |
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308 | IF ( .NOT.LSAME( UPLO , 'U' ).AND. & |
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309 | .NOT.LSAME( UPLO , 'L' ) )THEN |
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310 | INFO = 1 |
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311 | ELSE IF( .NOT.LSAME( TRANS, 'N' ).AND. & |
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312 | .NOT.LSAME( TRANS, 'T' ).AND. & |
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313 | .NOT.LSAME( TRANS, 'C' ) )THEN |
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314 | INFO = 2 |
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315 | ELSE IF( .NOT.LSAME( DIAG , 'U' ).AND. & |
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316 | .NOT.LSAME( DIAG , 'N' ) )THEN |
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317 | INFO = 3 |
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318 | ELSE IF( N < 0 )THEN |
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319 | INFO = 4 |
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320 | ELSE IF( LDA < MAX( 1, N ) )THEN |
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321 | INFO = 6 |
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322 | ELSE IF( INCX == 0 )THEN |
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323 | INFO = 8 |
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324 | END IF |
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325 | IF( INFO /= 0 )THEN |
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326 | CALL XERBLA( 'DTRSV ', INFO ) |
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327 | RETURN |
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328 | END IF |
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329 | |
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330 | !! Quick return if possible. |
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331 | |
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332 | IF( N == 0 ) RETURN |
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333 | |
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334 | NOUNIT = LSAME( DIAG, 'N' ) |
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335 | |
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336 | !! Set up the start point in X if the increment is not unity. This |
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337 | !! will be ( N - 1 )*INCX too small for descending loops. |
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338 | |
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339 | IF( INCX <= 0 )THEN |
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340 | KX = 1 - ( N - 1 )*INCX |
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341 | ELSE IF( INCX /= 1 )THEN |
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342 | KX = 1 |
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343 | END IF |
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344 | |
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345 | !! Start the operations. In this version the elements of A are |
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346 | !! accessed sequentially with one pass through A. |
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347 | |
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348 | IF( LSAME( TRANS, 'N' ) )THEN |
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349 | |
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350 | !! Form x := inv( A )*x. |
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351 | |
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352 | IF( LSAME( UPLO, 'U' ) )THEN |
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353 | IF( INCX == 1 )THEN |
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354 | DO 20, J = N, 1, -1 |
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355 | IF( X( J ) /= ZERO )THEN |
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356 | IF( NOUNIT ) X( J ) = X( J )/A( J, J ) |
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357 | TEMP = X( J ) |
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358 | DO 10, I = J - 1, 1, -1 |
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359 | X( I ) = X( I ) - TEMP*A( I, J ) |
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360 | 10 CONTINUE |
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361 | END IF |
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362 | 20 CONTINUE |
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363 | ELSE |
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364 | JX = KX + ( N - 1 )*INCX |
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365 | DO 40, J = N, 1, -1 |
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366 | IF( X( JX ) /= ZERO )THEN |
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367 | IF( NOUNIT ) X( JX ) = X( JX )/A( J, J ) |
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368 | TEMP = X( JX ) |
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369 | IX = JX |
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370 | DO 30, I = J - 1, 1, -1 |
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371 | IX = IX - INCX |
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372 | X( IX ) = X( IX ) - TEMP*A( I, J ) |
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373 | 30 CONTINUE |
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374 | END IF |
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375 | JX = JX - INCX |
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376 | 40 CONTINUE |
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377 | END IF |
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378 | ELSE |
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379 | IF( INCX == 1 )THEN |
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380 | DO 60, J = 1, N |
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381 | IF( X( J ) /= ZERO )THEN |
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382 | IF( NOUNIT ) X( J ) = X( J )/A( J, J ) |
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383 | TEMP = X( J ) |
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384 | DO 50, I = J + 1, N |
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385 | X( I ) = X( I ) - TEMP*A( I, J ) |
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386 | 50 CONTINUE |
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387 | END IF |
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388 | 60 CONTINUE |
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389 | ELSE |
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390 | JX = KX |
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391 | DO 80, J = 1, N |
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392 | IF( X( JX ) /= ZERO )THEN |
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393 | IF( NOUNIT ) X( JX ) = X( JX )/A( J, J ) |
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394 | TEMP = X( JX ) |
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395 | IX = JX |
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396 | DO 70, I = J + 1, N |
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397 | IX = IX + INCX |
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398 | X( IX ) = X( IX ) - TEMP*A( I, J ) |
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399 | 70 CONTINUE |
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400 | END IF |
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401 | JX = JX + INCX |
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402 | 80 CONTINUE |
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403 | END IF |
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404 | END IF |
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405 | ELSE |
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406 | |
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407 | !! Form x := inv( A' )*x. |
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408 | |
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409 | IF( LSAME( UPLO, 'U' ) )THEN |
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410 | IF( INCX == 1 )THEN |
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411 | DO 100, J = 1, N |
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412 | TEMP = X( J ) |
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413 | DO 90, I = 1, J - 1 |
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414 | TEMP = TEMP - A( I, J )*X( I ) |
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415 | 90 CONTINUE |
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416 | IF( NOUNIT ) TEMP = TEMP/A( J, J ) |
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417 | X( J ) = TEMP |
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418 | 100 CONTINUE |
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419 | ELSE |
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420 | JX = KX |
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421 | DO 120, J = 1, N |
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422 | TEMP = X( JX ) |
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423 | IX = KX |
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424 | DO 110, I = 1, J - 1 |
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425 | TEMP = TEMP - A( I, J )*X( IX ) |
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426 | IX = IX + INCX |
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427 | 110 CONTINUE |
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428 | IF( NOUNIT ) TEMP = TEMP/A( J, J ) |
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429 | X( JX ) = TEMP |
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430 | JX = JX + INCX |
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431 | 120 CONTINUE |
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432 | END IF |
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433 | ELSE |
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434 | IF( INCX == 1 )THEN |
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435 | DO 140, J = N, 1, -1 |
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436 | TEMP = X( J ) |
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437 | DO 130, I = N, J + 1, -1 |
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438 | TEMP = TEMP - A( I, J )*X( I ) |
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439 | 130 CONTINUE |
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440 | IF( NOUNIT ) TEMP = TEMP/A( J, J ) |
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441 | X( J ) = TEMP |
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442 | 140 CONTINUE |
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443 | ELSE |
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444 | KX = KX + ( N - 1 )*INCX |
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445 | JX = KX |
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446 | DO 160, J = N, 1, -1 |
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447 | TEMP = X( JX ) |
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448 | IX = KX |
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449 | DO 150, I = N, J + 1, -1 |
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450 | TEMP = TEMP - A( I, J )*X( IX ) |
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451 | IX = IX - INCX |
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452 | 150 CONTINUE |
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453 | IF( NOUNIT ) TEMP = TEMP/A( J, J ) |
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454 | X( JX ) = TEMP |
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455 | JX = JX - INCX |
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456 | 160 CONTINUE |
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457 | END IF |
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458 | END IF |
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459 | END IF |
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460 | |
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461 | END SUBROUTINE DTRSV |
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462 | !--------------------------------------------------------- |
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463 | SUBROUTINE DGER ( M, N, ALPHA, X, INCX, Y, INCY, A, LDA ) |
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464 | !! .. Scalar Arguments .. |
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465 | ! DOUBLE PRECISION ALPHA |
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466 | REAL (kind=8) :: ALPHA |
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467 | INTEGER INCX, INCY, LDA, M, N |
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468 | !! .. Array Arguments .. |
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469 | ! DOUBLE PRECISION A( LDA, * ), X( * ), Y( * ) |
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470 | REAL (kind=8) :: A( LDA, * ), X( * ), Y( * ) |
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471 | !! .. |
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472 | |
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473 | !! Purpose |
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474 | !! ======= |
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475 | |
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476 | !! DGER performs the rank 1 operation |
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477 | |
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478 | !! A := alpha*x*y' + A, |
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479 | |
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480 | !! where alpha is a scalar, x is an m element vector, y is an n element |
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481 | !! vector and A is an m by n matrix. |
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482 | |
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483 | !! Parameters |
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484 | !! ========== |
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485 | |
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486 | !! M - INTEGER. |
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487 | !! On entry, M specifies the number of rows of the matrix A. |
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488 | !! M must be at least zero. |
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489 | !! Unchanged on exit. |
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490 | |
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491 | !! N - INTEGER. |
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492 | !! On entry, N specifies the number of columns of the matrix A. |
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493 | !! N must be at least zero. |
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494 | !! Unchanged on exit. |
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495 | |
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496 | !! ALPHA - DOUBLE PRECISION. |
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497 | !! On entry, ALPHA specifies the scalar alpha. |
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498 | !! Unchanged on exit. |
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499 | |
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500 | !! X - DOUBLE PRECISION array of dimension at least |
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501 | !! ( 1 + ( m - 1 )*abs( INCX ) ). |
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502 | !! Before entry, the incremented array X must contain the m |
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503 | !! element vector x. |
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504 | !! Unchanged on exit. |
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505 | |
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506 | !! INCX - INTEGER. |
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507 | !! On entry, INCX specifies the increment for the elements of |
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508 | !! X. INCX must not be zero. |
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509 | !! Unchanged on exit. |
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510 | |
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511 | !! Y - DOUBLE PRECISION array of dimension at least |
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512 | !! ( 1 + ( n - 1 )*abs( INCY ) ). |
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513 | !! Before entry, the incremented array Y must contain the n |
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514 | !! element vector y. |
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515 | !! Unchanged on exit. |
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516 | |
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517 | !! INCY - INTEGER. |
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518 | !! On entry, INCY specifies the increment for the elements of |
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519 | !! Y. INCY must not be zero. |
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520 | !! Unchanged on exit. |
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521 | |
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522 | !! A - DOUBLE PRECISION array of DIMENSION ( LDA, n ). |
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523 | !! Before entry, the leading m by n part of the array A must |
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524 | !! contain the matrix of coefficients. On exit, A is |
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525 | !! overwritten by the updated matrix. |
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526 | |
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527 | !! LDA - INTEGER. |
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528 | !! On entry, LDA specifies the first dimension of A as declared |
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529 | !! in the calling (sub) program. LDA must be at least |
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530 | !! max( 1, m ). |
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531 | !! Unchanged on exit. |
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532 | |
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533 | |
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534 | !! Level 2 Blas routine. |
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535 | |
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536 | !! -- Written on 22-October-1986. |
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537 | !! Jack Dongarra, Argonne National Lab. |
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538 | !! Jeremy Du Croz, Nag Central Office. |
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539 | !! Sven Hammarling, Nag Central Office. |
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540 | !! Richard Hanson, Sandia National Labs. |
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541 | |
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542 | |
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543 | !! .. Parameters .. |
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544 | ! DOUBLE PRECISION ZERO |
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545 | ! PARAMETER ( ZERO = 0.0D+0 ) |
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546 | REAL (kind=8) :: ZERO |
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547 | PARAMETER ( ZERO = 0.0 ) |
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548 | !! .. Local Scalars .. |
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549 | ! DOUBLE PRECISION TEMP |
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550 | REAL (kind=8) :: TEMP |
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551 | INTEGER I, INFO, IX, J, JY, KX |
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552 | !! .. External Subroutines .. |
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553 | EXTERNAL XERBLA |
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554 | !! .. Intrinsic Functions .. |
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555 | INTRINSIC MAX |
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556 | !! .. |
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557 | !! .. Executable Statements .. |
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558 | |
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559 | !! Test the input parameters. |
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560 | |
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561 | INFO = 0 |
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562 | IF ( M < 0 )THEN |
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563 | INFO = 1 |
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564 | ELSE IF( N < 0 )THEN |
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565 | INFO = 2 |
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566 | ELSE IF( INCX == 0 )THEN |
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567 | INFO = 5 |
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568 | ELSE IF( INCY == 0 )THEN |
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569 | INFO = 7 |
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570 | ELSE IF( LDA < MAX( 1, M ) )THEN |
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571 | INFO = 9 |
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572 | END IF |
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573 | IF( INFO /= 0 )THEN |
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574 | CALL XERBLA( 'DGER ', INFO ) |
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575 | RETURN |
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576 | END IF |
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577 | |
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578 | !! Quick return if possible. |
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579 | |
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580 | IF( ( M == 0 ).OR.( N == 0 ).OR.( ALPHA == ZERO ) ) & |
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581 | RETURN |
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582 | |
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583 | !! Start the operations. In this version the elements of A are |
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584 | !! accessed sequentially with one pass through A. |
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585 | |
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586 | IF( INCY > 0 )THEN |
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587 | JY = 1 |
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588 | ELSE |
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589 | JY = 1 - ( N - 1 )*INCY |
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590 | END IF |
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591 | IF( INCX == 1 )THEN |
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592 | DO 20, J = 1, N |
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593 | IF( Y( JY ) /= ZERO )THEN |
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594 | TEMP = ALPHA*Y( JY ) |
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595 | DO 10, I = 1, M |
---|
596 | A( I, J ) = A( I, J ) + X( I )*TEMP |
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597 | 10 CONTINUE |
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598 | END IF |
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599 | JY = JY + INCY |
---|
600 | 20 CONTINUE |
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601 | ELSE |
---|
602 | IF( INCX > 0 )THEN |
---|
603 | KX = 1 |
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604 | ELSE |
---|
605 | KX = 1 - ( M - 1 )*INCX |
---|
606 | END IF |
---|
607 | DO 40, J = 1, N |
---|
608 | IF( Y( JY ) /= ZERO )THEN |
---|
609 | TEMP = ALPHA*Y( JY ) |
---|
610 | IX = KX |
---|
611 | DO 30, I = 1, M |
---|
612 | A( I, J ) = A( I, J ) + X( IX )*TEMP |
---|
613 | IX = IX + INCX |
---|
614 | 30 CONTINUE |
---|
615 | END IF |
---|
616 | JY = JY + INCY |
---|
617 | 40 CONTINUE |
---|
618 | END IF |
---|
619 | |
---|
620 | END SUBROUTINE DGER |
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621 | !--------------------------------------------------------- |
---|
622 | SUBROUTINE XERBLA ( SRNAME, INFO ) |
---|
623 | !! .. Scalar Arguments .. |
---|
624 | INTEGER INFO |
---|
625 | CHARACTER (len=6) :: SRNAME |
---|
626 | !! .. |
---|
627 | |
---|
628 | !! Purpose |
---|
629 | !! ======= |
---|
630 | |
---|
631 | !! XERBLA is an error handler for the Level 2 BLAS routines. |
---|
632 | |
---|
633 | !! It is called by the Level 2 BLAS routines if an input parameter is |
---|
634 | !! invalid. |
---|
635 | |
---|
636 | !! Installers should consider modifying the STOP statement in order to |
---|
637 | !! call system-specific exception-handling facilities. |
---|
638 | |
---|
639 | !! Parameters |
---|
640 | !! ========== |
---|
641 | |
---|
642 | !! SRNAME - CHARACTER*6. |
---|
643 | !! On entry, SRNAME specifies the name of the routine which |
---|
644 | !! called XERBLA. |
---|
645 | |
---|
646 | !! INFO - INTEGER. |
---|
647 | !! On entry, INFO specifies the position of the invalid |
---|
648 | !! parameter in the parameter-list of the calling routine. |
---|
649 | |
---|
650 | |
---|
651 | !! Auxiliary routine for Level 2 Blas. |
---|
652 | |
---|
653 | !! Written on 20-July-1986. |
---|
654 | |
---|
655 | !! .. Executable Statements .. |
---|
656 | |
---|
657 | WRITE (*,99999) SRNAME, INFO |
---|
658 | |
---|
659 | STOP |
---|
660 | |
---|
661 | 99999 FORMAT ( ' ** On entry to ', A6, ' parameter number ', I2, & |
---|
662 | ' had an illegal value' ) |
---|
663 | |
---|
664 | END SUBROUTINE XERBLA |
---|
665 | !----------------------------------------------------------- |
---|
666 | FUNCTION lsame( c1, c2 ) |
---|
667 | logical lsame |
---|
668 | CHARACTER (len=*), INTENT(in) :: c1, c2 |
---|
669 | IF( c1 == c2 ) THEN |
---|
670 | lsame=.TRUE. |
---|
671 | ELSE |
---|
672 | lsame=.FALSE. |
---|
673 | ENDIF |
---|
674 | END FUNCTION lsame |
---|