1 | C**** |
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2 | C ***************************** |
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3 | C * OASIS MODULE - LEVEL ? * |
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4 | C * ------------- ------- * |
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5 | C ***************************** |
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6 | C |
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7 | C**** remap_bilinear_reduced - calculate reduced grid bilinear remapping |
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8 | C |
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9 | C Purpose: |
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10 | C ------- |
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11 | C Adaptation of SCRIP 1.4 remap_bilinear module to calculate |
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12 | C bilinear remapping for reduced grids. |
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13 | C |
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14 | C** Interface: |
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15 | C --------- |
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16 | C *CALL* *remap_bilin_reduced* |
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17 | C |
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18 | C Input: |
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19 | C ----- |
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20 | C |
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21 | C Output: |
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22 | C ------ |
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23 | C |
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24 | C History: |
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25 | C ------- |
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26 | C Version Programmer Date Description |
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27 | C ------- ---------- ---- ----------- |
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28 | C 2.5 D. Declat 2002/07 created |
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29 | C 2.5 S. Valcke 2002/09 modified |
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30 | C |
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31 | C %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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32 | !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! |
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33 | ! |
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34 | ! this module contains necessary routines for performing an |
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35 | ! bilinear interpolation on reduced grids. |
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36 | ! |
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37 | !----------------------------------------------------------------------- |
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38 | ! |
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39 | ! CVS:$Id: remap_bilinear_reduced.f 2826 2010-12-10 11:14:21Z valcke $ |
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40 | ! |
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41 | ! Copyright (c) 1997, 1998 the Regents of the University of |
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42 | ! California. |
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43 | ! |
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44 | ! This software and ancillary information (herein called software) |
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45 | ! called SCRIP is made available under the terms described here. |
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46 | ! The software has been approved for release with associated |
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47 | ! LA-CC Number 98-45. |
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48 | ! |
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49 | ! Unless otherwise indicated, this software has been authored |
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50 | ! by an employee or employees of the University of California, |
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51 | ! operator of the Los Alamos National Laboratory under Contract |
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52 | ! No. W-7405-ENG-36 with the U.S. Department of Energy. The U.S. |
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53 | ! Government has rights to use, reproduce, and distribute this |
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54 | ! software. The public may copy and use this software without |
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55 | ! charge, provided that this Notice and any statement of authorship |
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56 | ! are reproduced on all copies. Neither the Government nor the |
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57 | ! University makes any warranty, express or implied, or assumes |
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58 | ! any liability or responsibility for the use of this software. |
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59 | ! |
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60 | ! If software is modified to produce derivative works, such modified |
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61 | ! software should be clearly marked, so as not to confuse it with |
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62 | ! the version available from Los Alamos National Laboratory. |
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63 | ! |
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64 | !*********************************************************************** |
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65 | |
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66 | module remap_bilinear_reduced |
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67 | |
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68 | !----------------------------------------------------------------------- |
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69 | |
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70 | use kinds_mod ! defines common data types |
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71 | use constants ! defines common constants |
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72 | use grids ! module containing grid info |
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73 | use remap_vars ! module containing remap info |
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74 | USE mod_oasis_flush |
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75 | |
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76 | implicit none |
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77 | |
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78 | !----------------------------------------------------------------------- |
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79 | |
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80 | integer (kind=int_kind), parameter :: |
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81 | & max_iter = 100 ! max iteration count for i,j iteration |
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82 | |
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83 | real (kind=dbl_kind), parameter :: |
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84 | & converge = 1.e-10_dbl_kind ! convergence criterion |
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85 | |
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86 | !*********************************************************************** |
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87 | |
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88 | contains |
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89 | |
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90 | !*********************************************************************** |
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91 | |
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92 | subroutine remap_bilin_reduced (lextrapdone) |
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93 | |
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94 | !----------------------------------------------------------------------- |
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95 | ! |
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96 | ! this routine computes the weights for a bilinear interpolation. |
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97 | ! |
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98 | !----------------------------------------------------------------------- |
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99 | |
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100 | LOGICAL :: |
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101 | & lextrapdone ! logical, true if EXTRAP done on field |
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102 | LOGICAL :: ll_nnei ! true (default) if extra search is done |
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103 | |
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104 | !----------------------------------------------------------------------- |
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105 | ! |
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106 | ! local variables |
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107 | ! |
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108 | !----------------------------------------------------------------------- |
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109 | |
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110 | integer (kind=int_kind) :: n, icount, i, |
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111 | & dst_add, ! destination address |
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112 | & iter, ! iteration counter |
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113 | & nmap ! index of current map being computed |
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114 | |
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115 | integer (kind=int_kind), dimension(4) :: |
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116 | & src_add ! address for the four source points |
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117 | |
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118 | real (kind=dbl_kind), dimension(4) :: |
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119 | & src_lats, ! latitudes of four bilinear corners |
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120 | & src_lons, ! longitudes of four bilinear corners |
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121 | & wgts ! bilinear weights for four corners |
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122 | |
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123 | real (kind=dbl_kind) :: |
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124 | & plat, plon, ! lat/lon coords of destination point |
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125 | & iguess, jguess, ! current guess for bilinear coordinate |
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126 | & deli, delj, ! corrections to i,j |
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127 | & dth1, dth2, dth3, ! some latitude differences |
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128 | & dph1, dph2, dph3, ! some longitude differences |
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129 | & dthp, dphp, ! difference between point and sw corner |
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130 | & mat1, mat2, mat3, mat4, ! matrix elements |
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131 | & determinant, ! matrix determinant |
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132 | & sum_wgts ! sum of weights for normalization |
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133 | |
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134 | real (kind=dbl_kind) :: |
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135 | & coslat_dst, sinlat_dst, coslon_dst, sinlon_dst, |
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136 | & dist_min, distance, ! for computing dist-weighted avg |
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137 | & src_latsnn, arg |
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138 | |
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139 | integer (kind=int_kind) :: min_add, max_add, srch_add, src_addnn |
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140 | |
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141 | !----------------------------------------------------------------------- |
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142 | ! |
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143 | ! compute mappings from grid1 to grid2 |
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144 | ! |
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145 | !----------------------------------------------------------------------- |
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146 | ! |
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147 | IF (nlogprt .GE. 2) THEN |
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148 | WRITE (UNIT = nulou,FMT = *)' ' |
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149 | WRITE (UNIT = nulou,FMT = *) |
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150 | & 'Entering routine remap_bilin_reduced' |
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151 | CALL OASIS_FLUSH_SCRIP(nulou) |
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152 | ENDIF |
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153 | ! |
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154 | ll_nnei = .true. |
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155 | nmap = 1 |
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156 | if (grid1_rank /= 2) then |
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157 | stop 'Can not do bilinear interpolation when grid_rank /= 2' |
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158 | endif |
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159 | |
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160 | !*** |
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161 | !*** loop over destination grid |
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162 | !*** |
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163 | |
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164 | grid_loop1: do dst_add = 1, grid2_size |
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165 | |
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166 | if (.not. grid2_mask(dst_add)) cycle grid_loop1 |
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167 | |
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168 | plat = grid2_center_lat(dst_add) |
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169 | plon = grid2_center_lon(dst_add) |
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170 | |
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171 | !*** |
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172 | !*** find nearest square of grid points on source grid |
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173 | !*** |
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174 | |
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175 | call grid_search_bilin_rd(src_add, src_lats, src_lons, |
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176 | & min_add, max_add, |
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177 | & plat, plon, grid1_dims, |
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178 | & grid1_center_lat, grid1_center_lon, |
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179 | & lextrapdone) |
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180 | if (src_add(1) > 0) THEN |
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181 | |
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182 | !*** |
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183 | !*** if the 4 surrounding points have been found and are |
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184 | !*** non-masked, do bilinear interpolation |
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185 | !*** |
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186 | |
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187 | grid2_frac(dst_add) = one |
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188 | |
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189 | !*** |
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190 | !*** iterate to find i,j for bilinear approximation |
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191 | !*** |
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192 | |
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193 | dth1 = src_lats(2) - src_lats(1) |
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194 | dth2 = src_lats(4) - src_lats(1) |
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195 | dth3 = src_lats(3) - src_lats(2) - dth2 |
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196 | |
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197 | dph1 = src_lons(2) - src_lons(1) |
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198 | dph2 = src_lons(4) - src_lons(1) |
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199 | dph3 = src_lons(3) - src_lons(2) |
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200 | |
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201 | if (dph1 > three*pih) dph1 = dph1 - pi2 |
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202 | if (dph2 > three*pih) dph2 = dph2 - pi2 |
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203 | if (dph3 > three*pih) dph3 = dph3 - pi2 |
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204 | if (dph1 < -three*pih) dph1 = dph1 + pi2 |
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205 | if (dph2 < -three*pih) dph2 = dph2 + pi2 |
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206 | if (dph3 < -three*pih) dph3 = dph3 + pi2 |
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207 | |
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208 | dph3 = dph3 - dph2 |
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209 | |
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210 | iguess = half |
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211 | jguess = half |
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212 | |
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213 | iter_loop1: do iter=1,max_iter |
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214 | |
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215 | dthp = plat - src_lats(1) - dth1*iguess - |
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216 | & dth2*jguess - dth3*iguess*jguess |
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217 | dphp = plon - src_lons(1) |
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218 | |
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219 | if (dphp > three*pih) dphp = dphp - pi2 |
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220 | if (dphp < -three*pih) dphp = dphp + pi2 |
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221 | |
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222 | dphp = dphp - dph1*iguess - dph2*jguess - |
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223 | & dph3*iguess*jguess |
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224 | |
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225 | mat1 = dth1 + dth3*jguess |
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226 | mat2 = dth2 + dth3*iguess |
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227 | mat3 = dph1 + dph3*jguess |
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228 | mat4 = dph2 + dph3*iguess |
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229 | |
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230 | determinant = mat1*mat4 - mat2*mat3 |
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231 | |
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232 | deli = (dthp*mat4 - mat2*dphp)/determinant |
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233 | delj = (mat1*dphp - dthp*mat3)/determinant |
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234 | |
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235 | if (abs(deli) < converge .and. |
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236 | & abs(delj) < converge) exit iter_loop1 |
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237 | |
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238 | iguess = iguess + deli |
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239 | jguess = jguess + delj |
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240 | |
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241 | end do iter_loop1 |
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242 | |
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243 | if (iter <= max_iter) then |
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244 | |
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245 | !*** |
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246 | !*** successfully found i,j - compute weights |
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247 | !*** |
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248 | |
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249 | wgts(1) = (one-iguess)*(one-jguess) |
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250 | wgts(2) = iguess*(one-jguess) |
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251 | wgts(3) = iguess*jguess |
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252 | wgts(4) = (one-iguess)*jguess |
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253 | call store_link_bilin(dst_add, src_add, wgts, nmap) |
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254 | else |
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255 | write(nulou,*) 'Point coords: ',plat,plon |
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256 | write(nulou,*) 'Dest grid lats: ',src_lats |
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257 | write(nulou,*) 'Dest grid lons: ',src_lons |
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258 | write(nulou,*) 'Dest grid addresses: ',src_add |
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259 | write(nulou,*) 'Current i,j : ',iguess, jguess |
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260 | write(nulou,*) |
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261 | & 'Iteration for i,j exceed max iteration count' |
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262 | stop |
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263 | endif |
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264 | |
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265 | else if (src_add(1) < 0) THEN |
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266 | |
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267 | !*** |
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268 | !*** We are in the first or last bin or at least one of the 4 |
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269 | !*** neighbours was masked. Do distance-weighted average using |
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270 | !*** the non-masked points among the 4 closest ones. |
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271 | |
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272 | IF (nlogprt .eq. 2) then |
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273 | WRITE(nulou,*) ' ' |
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274 | WRITE(nulou,*) |
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275 | & 'WARNING: Cannot make bilinear interpolation for target point' |
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276 | & ,dst_add |
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277 | WRITE(nulou,*) |
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278 | & 'Using non-masked points among 4 nearest neighbors.' |
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279 | CALL OASIS_FLUSH_SCRIP(nulou) |
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280 | ENDIF |
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281 | |
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282 | !*** |
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283 | !*** Find the 4 closest points |
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284 | !*** |
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285 | |
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286 | coslat_dst = cos(plat) |
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287 | sinlat_dst = sin(plat) |
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288 | coslon_dst = cos(plon) |
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289 | sinlon_dst = sin(plon) |
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290 | src_add = 0 |
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291 | dist_min = bignum |
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292 | src_lats = bignum |
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293 | IF (min_add == 0) min_add = 1 |
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294 | IF (max_add > grid1_size) max_add = grid1_size |
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295 | do srch_add = min_add,max_add |
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296 | arg = coslat_dst*cos(grid1_center_lat(srch_add))* |
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297 | & (coslon_dst*cos(grid1_center_lon(srch_add)) + |
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298 | & sinlon_dst*sin(grid1_center_lon(srch_add)))+ |
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299 | & sinlat_dst*sin(grid1_center_lat(srch_add)) |
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300 | IF (arg < -1.0d0) THEN |
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301 | arg = -1.0d0 |
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302 | ELSE IF (arg > 1.0d0) THEN |
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303 | arg = 1.0d0 |
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304 | END IF |
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305 | distance=acos(arg) |
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306 | |
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307 | if (distance < dist_min) then |
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308 | sort_loop: do n=1,4 |
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309 | if (distance < src_lats(n)) then |
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310 | do i=4,n+1,-1 |
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311 | src_add (i) = src_add (i-1) |
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312 | src_lats(i) = src_lats(i-1) |
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313 | end do |
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314 | src_add (n) = srch_add |
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315 | src_lats(n) = distance |
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316 | dist_min = src_lats(4) |
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317 | exit sort_loop |
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318 | endif |
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319 | end do sort_loop |
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320 | endif |
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321 | end do |
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322 | |
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323 | src_lons = one/(src_lats + tiny) |
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324 | distance = sum(src_lons) |
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325 | src_lats = src_lons/distance |
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326 | |
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327 | !*** |
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328 | !*** Among 4 closest points, keep only the non-masked ones |
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329 | !*** |
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330 | |
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331 | icount = 0 |
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332 | do n=1,4 |
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333 | if (grid1_mask(src_add(n)) .or. |
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334 | & (.not. grid1_mask(src_add(n)) .and. lextrapdone)) then |
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335 | icount = icount + 1 |
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336 | else |
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337 | src_lats(n) = zero |
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338 | endif |
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339 | end do |
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340 | |
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341 | if (icount > 0) then |
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342 | !*** renormalize weights |
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343 | sum_wgts = sum(src_lats) |
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344 | wgts(1) = src_lats(1)/sum_wgts |
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345 | wgts(2) = src_lats(2)/sum_wgts |
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346 | wgts(3) = src_lats(3)/sum_wgts |
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347 | wgts(4) = src_lats(4)/sum_wgts |
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348 | |
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349 | grid2_frac(dst_add) = one |
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350 | call store_link_bilin(dst_add, src_add, wgts, nmap) |
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351 | ELSE |
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352 | IF (ll_nnei .eqv. .true. ) then |
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353 | IF (nlogprt .ge. 2) THEN |
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354 | WRITE(nulou,*) ' ' |
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355 | WRITE(nulou,*) |
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356 | & 'All 4 surrounding source grid points are masked' |
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357 | WRITE(nulou,*) 'for target point ',dst_add |
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358 | WRITE(nulou,*) 'with longitude and latitude', |
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359 | & plon, plat |
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360 | WRITE(nulou,*) |
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361 | & 'Using the nearest non-masked neighbour.' |
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362 | CALL OASIS_FLUSH_SCRIP(nulou) |
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363 | ENDIF |
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364 | src_latsnn = bignum |
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365 | !cdir novector |
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366 | do srch_add = min_add,max_add |
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367 | if (grid1_mask(srch_add) .or. |
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368 | & (.not. grid1_mask(srch_add) .and. lextrapdone)) THEN |
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369 | arg = coslat_dst*cos(grid1_center_lat(srch_add))* |
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370 | & (coslon_dst*cos(grid1_center_lon(srch_add)) + |
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371 | & sinlon_dst*sin(grid1_center_lon(srch_add)))+ |
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372 | & sinlat_dst*sin(grid1_center_lat(srch_add)) |
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373 | IF (arg < -1.0d0) THEN |
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374 | arg = -1.0d0 |
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375 | ELSE IF (arg > 1.0d0) THEN |
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376 | arg = 1.0d0 |
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377 | END IF |
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378 | distance=acos(arg) |
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379 | |
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380 | if (distance < src_latsnn) then |
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381 | src_addnn = srch_add |
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382 | src_latsnn = distance |
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383 | endif |
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384 | endif |
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385 | end DO |
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386 | IF (nlogprt .ge. 2) THEN |
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387 | WRITE(nulou,*) |
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388 | & 'Nearest non masked neighbour is source point ' |
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389 | & ,src_addnn |
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390 | WRITE(nulou,*) 'with longitude and latitude', |
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391 | & grid1_center_lon(src_addnn), |
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392 | & grid1_center_lat(src_addnn) |
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393 | WRITE(nulou,*) ' ' |
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394 | CALL OASIS_FLUSH_SCRIP(nulou) |
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395 | ENDIF |
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396 | wgts(1) = 1. |
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397 | wgts(2) = 0. |
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398 | wgts(3) = 0. |
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399 | wgts(4) = 0. |
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400 | src_add(1) = src_addnn |
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401 | src_add(2) = 0 |
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402 | src_add(3) = 0 |
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403 | src_add(4) = 0 |
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404 | |
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405 | grid2_frac(dst_add) = one |
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406 | call store_link_bilin(dst_add, src_add, wgts, nmap) |
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407 | endif |
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408 | ENDIF |
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409 | ENDIF |
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410 | end do grid_loop1 |
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411 | ! |
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412 | !----------------------------------------------------------------------- |
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413 | |
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414 | end subroutine remap_bilin_reduced |
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415 | |
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416 | !*********************************************************************** |
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417 | |
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418 | subroutine grid_search_bilin_rd(src_add, src_lats, src_lons, |
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419 | & min_add, max_add, |
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420 | & plat, plon, src_grid_dims, |
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421 | & src_center_lat, src_center_lon, |
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422 | & lextrapdone) |
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423 | |
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424 | !----------------------------------------------------------------------- |
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425 | ! |
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426 | ! this routine finds the location of the search point plat, plon |
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427 | ! in the source grid and returns the corners needed for a bilinear |
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428 | ! interpolation. The target grid is a reduced grid. |
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429 | ! |
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430 | !----------------------------------------------------------------------- |
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431 | |
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432 | !----------------------------------------------------------------------- |
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433 | ! |
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434 | ! output variables |
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435 | ! |
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436 | !----------------------------------------------------------------------- |
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437 | |
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438 | integer (kind=int_kind), dimension(4), intent(out) :: |
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439 | & src_add ! address of each corner point enclosing P |
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440 | |
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441 | real (kind=dbl_kind), dimension(4), intent(out) :: |
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442 | & src_lats, ! latitudes of the four corner points |
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443 | & src_lons ! longitudes of the four corner points |
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444 | |
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445 | integer (kind=int_kind) :: min_add, max_add |
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446 | |
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447 | !----------------------------------------------------------------------- |
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448 | ! |
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449 | ! input variables |
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450 | ! |
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451 | !----------------------------------------------------------------------- |
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452 | |
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453 | real (kind=dbl_kind), intent(in) :: |
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454 | & plat, ! latitude of the search point |
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455 | & plon ! longitude of the search point |
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456 | |
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457 | integer (kind=int_kind), dimension(2), intent(in) :: |
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458 | & src_grid_dims ! size of each src grid dimension |
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459 | |
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460 | real (kind=dbl_kind), dimension(:), intent(in) :: |
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461 | & src_center_lat, ! latitude of each src grid center |
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462 | & src_center_lon ! longitude of each src grid center |
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463 | |
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464 | LOGICAL :: |
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465 | & lextrapdone ! logical, true if EXTRAP done on field |
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466 | |
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467 | !----------------------------------------------------------------------- |
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468 | ! |
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469 | ! local variables |
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470 | ! |
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471 | !----------------------------------------------------------------------- |
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472 | |
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473 | integer (kind=int_kind) :: n, next_n, srch_add, ni, ! dummy indices |
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474 | & nx, ny, ntotmask, ! dimensions of src grid |
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475 | & inter_add ! add for restricting search |
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476 | ! |
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477 | integer (kind=int_kind), DIMENSION(4) :: src_bid |
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478 | |
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479 | !----------------------------------------------------------------------- |
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480 | ! |
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481 | ! restrict search first using bins |
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482 | ! |
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483 | !----------------------------------------------------------------------- |
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484 | |
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485 | nx = src_grid_dims(1) |
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486 | inter_add = 0 |
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487 | |
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488 | src_add = 0 |
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489 | |
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490 | min_add = size(src_center_lat) + 1 |
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491 | max_add = 1 |
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492 | if (plat >= bin_lats_r(1,1)) then |
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493 | min_add = 0 |
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494 | max_add = bin_addr1_r(4,1) |
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495 | inter_add = bin_addr1_r(3,1) |
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496 | else if (plat <= bin_lats_r(1,num_srch_red)) then |
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497 | max_add = nx + 1 |
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498 | min_add = bin_addr1_r(1,num_srch_red) |
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499 | inter_add = bin_addr1_r(3,num_srch_red) |
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500 | else |
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501 | srch_loopred: do n=1,num_srch_red |
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502 | if (plat <= bin_lats_r(1,n) |
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503 | & .and. plat >= bin_lats_r(2,n)) then |
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504 | min_add = bin_addr1_r(1,n) |
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505 | max_add = bin_addr1_r(4,n) |
---|
506 | inter_add = bin_addr1_r(3,n) |
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507 | exit srch_loopred |
---|
508 | endif |
---|
509 | end DO srch_loopred |
---|
510 | ENDIF |
---|
511 | |
---|
512 | !----------------------------------------------------------------------- |
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513 | ! |
---|
514 | ! now perform a more detailed search |
---|
515 | ! |
---|
516 | !----------------------------------------------------------------------- |
---|
517 | if (min_add .ne. 0 .and. max_add .ne. nx+1) THEN |
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518 | !*** The concerned bins are not the top north or south ones. |
---|
519 | !*** We should be able to find the four corners |
---|
520 | !*** for the bilinear interpolation. |
---|
521 | |
---|
522 | IF ( plon <= src_center_lon(min_add) ) THEN |
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523 | src_add(1) = inter_add-1 |
---|
524 | src_add(2) = min_add |
---|
525 | ELSE IF ( plon > src_center_lon(inter_add-1) ) then |
---|
526 | src_add(1) = inter_add-1 |
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527 | src_add(2) = min_add |
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528 | else |
---|
529 | srch_loop2: do srch_add = min_add, inter_add-2 |
---|
530 | if ( (plon > src_center_lon(srch_add)) .and. |
---|
531 | & (plon <= src_center_lon(srch_add+1)) )then |
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532 | src_add(1) = srch_add |
---|
533 | src_add(2) = srch_add+1 |
---|
534 | exit srch_loop2 |
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535 | endif |
---|
536 | end do srch_loop2 |
---|
537 | ENDIF |
---|
538 | IF ( plon <= src_center_lon(inter_add) ) THEN |
---|
539 | src_add(3) = max_add |
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540 | src_add(4) = inter_add |
---|
541 | ELSE IF ( plon >= src_center_lon(max_add) ) then |
---|
542 | src_add(3) = max_add |
---|
543 | src_add(4) = inter_add |
---|
544 | else |
---|
545 | srch_loop3: do srch_add = inter_add, max_add |
---|
546 | if ( (plon >= src_center_lon(srch_add)) .and. |
---|
547 | & (plon <= src_center_lon(srch_add+1)) )then |
---|
548 | src_add(3) = srch_add |
---|
549 | src_add(4) = srch_add+1 |
---|
550 | exit srch_loop3 |
---|
551 | endif |
---|
552 | enddo srch_loop3 |
---|
553 | ENDIF |
---|
554 | src_lats(1) = src_center_lat(src_add(3)) |
---|
555 | src_lats(2) = src_center_lat(src_add(4)) |
---|
556 | src_lats(3) = src_center_lat(src_add(2)) |
---|
557 | src_lats(4) = src_center_lat(src_add(1)) |
---|
558 | |
---|
559 | src_lons(1) = src_center_lon(src_add(3)) |
---|
560 | src_lons(2) = src_center_lon(src_add(4)) |
---|
561 | src_lons(3) = src_center_lon(src_add(2)) |
---|
562 | src_lons(4) = src_center_lon(src_add(1)) |
---|
563 | |
---|
564 | src_bid=src_add |
---|
565 | |
---|
566 | src_add(1) = src_bid(3) |
---|
567 | src_add(2) = src_bid(4) |
---|
568 | src_add(3) = src_bid(2) |
---|
569 | src_add(4) = src_bid(1) |
---|
570 | |
---|
571 | ! Check if one point is masked; IF so, nearest-neighbour |
---|
572 | ! interpolation will be used |
---|
573 | |
---|
574 | ntotmask = 0 |
---|
575 | do ni=1,4 |
---|
576 | if (.not. grid1_mask(src_add(ni)).and. |
---|
577 | & .not. lextrapdone) |
---|
578 | & ntotmask = ntotmask + 1 |
---|
579 | end DO |
---|
580 | IF (ntotmask .gt. 0) src_add(1) = -src_add(1) |
---|
581 | |
---|
582 | ELSE |
---|
583 | |
---|
584 | !*** We are in the first or last bin. Put src_add = -1 so that |
---|
585 | !*** distance-weighted average of the 4 non-masked closest points |
---|
586 | !*** is done in calling routine. |
---|
587 | |
---|
588 | src_add = -1 |
---|
589 | |
---|
590 | ENDIF |
---|
591 | |
---|
592 | !----------------------------------------------------------------------- |
---|
593 | |
---|
594 | end subroutine grid_search_bilin_rd |
---|
595 | |
---|
596 | !*********************************************************************** |
---|
597 | |
---|
598 | subroutine store_link_bilin(dst_add, src_add, weights, nmap) |
---|
599 | |
---|
600 | !----------------------------------------------------------------------- |
---|
601 | ! |
---|
602 | ! this routine stores the address and weight for four links |
---|
603 | ! associated with one destination point in the appropriate address |
---|
604 | ! and weight arrays and resizes those arrays if necessary. |
---|
605 | ! |
---|
606 | !----------------------------------------------------------------------- |
---|
607 | |
---|
608 | !----------------------------------------------------------------------- |
---|
609 | ! |
---|
610 | ! input variables |
---|
611 | ! |
---|
612 | !----------------------------------------------------------------------- |
---|
613 | |
---|
614 | integer (kind=int_kind), intent(in) :: |
---|
615 | & dst_add, ! address on destination grid |
---|
616 | & nmap ! identifies which direction for mapping |
---|
617 | |
---|
618 | integer (kind=int_kind), dimension(4), intent(in) :: |
---|
619 | & src_add ! addresses on source grid |
---|
620 | |
---|
621 | real (kind=dbl_kind), dimension(4), intent(in) :: |
---|
622 | & weights ! array of remapping weights for these links |
---|
623 | |
---|
624 | !----------------------------------------------------------------------- |
---|
625 | ! |
---|
626 | ! local variables |
---|
627 | ! |
---|
628 | !----------------------------------------------------------------------- |
---|
629 | |
---|
630 | integer (kind=int_kind) :: n, ! dummy index |
---|
631 | & num_links_old ! placeholder for old link number |
---|
632 | |
---|
633 | !----------------------------------------------------------------------- |
---|
634 | ! |
---|
635 | ! increment number of links and check to see if remap arrays need |
---|
636 | ! to be increased to accomodate the new link. then store the |
---|
637 | ! link. |
---|
638 | ! |
---|
639 | !----------------------------------------------------------------------- |
---|
640 | |
---|
641 | select case (nmap) |
---|
642 | case(1) |
---|
643 | |
---|
644 | num_links_old = num_links_map1 |
---|
645 | num_links_map1 = num_links_old + 4 |
---|
646 | |
---|
647 | if (num_links_map1 > max_links_map1) |
---|
648 | & call resize_remap_vars(1,resize_increment) |
---|
649 | |
---|
650 | do n=1,4 |
---|
651 | grid1_add_map1(num_links_old+n) = src_add(n) |
---|
652 | grid2_add_map1(num_links_old+n) = dst_add |
---|
653 | wts_map1 (1,num_links_old+n) = weights(n) |
---|
654 | end do |
---|
655 | |
---|
656 | case(2) |
---|
657 | |
---|
658 | num_links_old = num_links_map2 |
---|
659 | num_links_map2 = num_links_old + 4 |
---|
660 | |
---|
661 | if (num_links_map2 > max_links_map2) |
---|
662 | & call resize_remap_vars(2,resize_increment) |
---|
663 | |
---|
664 | do n=1,4 |
---|
665 | grid1_add_map2(num_links_old+n) = dst_add |
---|
666 | grid2_add_map2(num_links_old+n) = src_add(n) |
---|
667 | wts_map2 (1,num_links_old+n) = weights(n) |
---|
668 | end do |
---|
669 | |
---|
670 | end select |
---|
671 | |
---|
672 | !----------------------------------------------------------------------- |
---|
673 | |
---|
674 | end subroutine store_link_bilin |
---|
675 | |
---|
676 | !*********************************************************************** |
---|
677 | |
---|
678 | end module remap_bilinear_reduced |
---|
679 | |
---|
680 | !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! |
---|