1 | MODULE fbgenerate_coords |
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2 | USE obs_fbm |
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3 | USE date_utils |
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4 | |
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5 | CONTAINS |
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6 | |
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7 | REAL(KIND=fbdp) FUNCTION fb_dates(timein,datein) |
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8 | IMPLICIT NONE |
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9 | INTEGER, INTENT(IN) :: timein ! Format: HHMM |
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10 | INTEGER, INTENT(IN) :: datein ! Format: YYYYMMDD |
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11 | INTEGER :: iyea,imon,iday |
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12 | INTEGER :: ihr,imin,isec |
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13 | |
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14 | iyea=datein/10000 |
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15 | imon=datein/100-iyea*100 |
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16 | iday=datein-iyea*10000-imon*100 |
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17 | |
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18 | ihr = timein/100 |
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19 | imin = timein - ihr*100 |
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20 | isec = 0 |
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21 | |
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22 | CALL greg2jul(isec,imin,ihr,iday,imon,iyea,fb_dates) |
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23 | |
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24 | END FUNCTION fb_dates |
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25 | |
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26 | |
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27 | |
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28 | SUBROUTINE set_spatial_coords(lats,lons,n,FillVal) |
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29 | IMPLICIT NONE |
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30 | INTEGER :: i, j, k, p, nlats, nlons, nlats_in_list, nlons_in_list |
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31 | INTEGER, INTENT(IN) :: n |
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32 | REAL(KIND=fbdp), INTENT(INOUT) :: lats(:), lons(:) |
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33 | REAL(KIND=fbdp) :: FillVal |
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34 | |
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35 | ! A single non-FillVal value should be replicated n times |
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36 | ! Three non-FillVal values should be used as the start, end, step in conjunction with n |
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37 | ! unless n is three, in which case treat as list, not bounds. |
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38 | ! A full list of n non-FillVals should be left unaltered. |
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39 | |
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40 | !Find number of lats and lons |
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41 | ! by finding number of non-FillVal entries in arrays |
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42 | ! and expanding bounds if necessary |
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43 | |
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44 | nlats_in_list = last_element(lats,FillVal) |
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45 | nlons_in_list = last_element(lons,FillVal) |
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46 | |
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47 | !Expand bounds only if 3 values given and number obs>3 |
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48 | IF (nlats_in_list == 1) THEN |
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49 | lats(1:nlats) = lats(1) |
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50 | ELSE IF ((nlats_in_list==3).AND.((n>3))) THEN ! Treat as list of three, not bounds |
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51 | CALL expand_bounds(lats, FillVal) |
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52 | END IF |
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53 | |
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54 | IF (nlons_in_list == 1) THEN |
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55 | lons(1:nlons) = lons(1) |
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56 | ELSE IF ((nlons_in_list==3).AND.((n>3))) THEN ! Treat as list of three, not bounds |
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57 | CALL expand_bounds(lons, FillVal) |
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58 | END IF |
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59 | |
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60 | nlats = last_element(lats,FillVal) |
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61 | nlons = last_element(lons,FillVal) |
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62 | |
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63 | IF ((n /= nlats) .AND. (n /= nlons)) THEN |
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64 | WRITE(*,*) "ERROR: Number of lat/lons not equal to nobs", nlats, nlons, n |
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65 | CALL abort |
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66 | END IF |
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67 | |
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68 | END SUBROUTINE set_spatial_coords |
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69 | |
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70 | |
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71 | SUBROUTINE set_spatial_coords_grid(lats,lons,n,nlats,nlons,FillVal) |
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72 | IMPLICIT NONE |
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73 | INTEGER :: i, j, k, p, nlats_in_list, nlons_in_list |
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74 | INTEGER, INTENT(IN) :: n, nlats, nlons |
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75 | REAL(KIND=fbdp), INTENT(INOUT) :: lats(:), lons(:) |
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76 | REAL(KIND=fbdp), ALLOCATABLE :: tmp_lats(:), tmp_lons(:) |
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77 | REAL(KIND=fbdp) :: FillVal |
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78 | |
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79 | ! A single non-FillVal value should be replicated n times |
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80 | ! Three non-FillVal values should be used as the start, end, step in conjunction with n |
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81 | ! unless n is three, in which case treat as list, not bounds. |
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82 | ! A full list of n non-FillVals should be left unaltered. |
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83 | |
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84 | !Find number of lats and lons in list |
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85 | ! by finding number of non-FillVal entries in arrays |
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86 | ! and then expand bounds if necessary |
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87 | |
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88 | nlats_in_list = last_element(lats,FillVal) |
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89 | nlons_in_list = last_element(lons,FillVal) |
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90 | |
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91 | !Expand bounds only if 3 values given and number lats (or lons) not equal to 3 |
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92 | IF (nlats_in_list == 1) THEN |
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93 | lats(1:nlats) = lats(1) |
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94 | ELSE IF ((nlats_in_list==3).AND.((nlats>3))) THEN ! Treat as bounds |
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95 | CALL expand_bounds(lats, FillVal) |
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96 | END IF |
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97 | |
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98 | IF (nlons_in_list == 1) THEN |
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99 | lons(1:nlons) = lons(1) |
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100 | ELSE IF ((nlons_in_list==3).AND.((nlons>3))) THEN ! Treat as bounds |
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101 | CALL expand_bounds(lons, FillVal) |
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102 | END IF |
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103 | |
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104 | nlats_in_list = last_element(lats,FillVal) |
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105 | nlons_in_list = last_element(lons,FillVal) |
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106 | |
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107 | |
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108 | IF ((nlats_in_list * nlons_in_list) == n) THEN |
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109 | ALLOCATE(tmp_lons(n)) |
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110 | ALLOCATE(tmp_lats(n)) |
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111 | k = 0 |
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112 | p = 0 |
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113 | DO i = 1, nlats |
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114 | p = p + 1 |
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115 | DO j = 1, nlons |
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116 | k = k + 1 |
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117 | tmp_lons(k) = lons(j) |
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118 | tmp_lats(k) = lats(p) |
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119 | END DO |
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120 | END DO |
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121 | lats(:) = tmp_lats(:) |
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122 | lons(:) = tmp_lons(:) |
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123 | DEALLOCATE(tmp_lons) |
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124 | DEALLOCATE(tmp_lats) |
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125 | ELSE |
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126 | WRITE(*,*) |
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127 | WRITE(*,*) "ERROR: Number of lat * lon values not equal to nobs", nlats_in_list, nlons_in_list, n |
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128 | CALL abort |
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129 | END IF |
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130 | |
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131 | END SUBROUTINE set_spatial_coords_grid |
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132 | |
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133 | |
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134 | SUBROUTINE set_spatial_coords_physpace(lats,lons,n,FillVal,phys_spacing) |
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135 | IMPLICIT NONE |
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136 | INTEGER :: i, j, k, nlats, nlons |
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137 | INTEGER, INTENT(IN) :: n |
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138 | REAL(KIND=fbdp), INTENT(INOUT) :: lats(:), lons(:) |
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139 | REAL(KIND=fbdp), ALLOCATABLE :: tmp_lats(:) |
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140 | REAL(KIND=fbdp) :: FillVal |
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141 | REAL(KIND=fbdp), PARAMETER :: earth_radius = 6371.0_fbdp ! km |
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142 | REAL(KIND=fbdp), PARAMETER :: pi = 3.141592654_fbdp |
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143 | REAL(KIND=fbdp), INTENT(IN) :: phys_spacing |
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144 | REAL(KIND=fbdp) :: lat_step |
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145 | |
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146 | ! Use physical spacing to set lats and lons |
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147 | |
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148 | nlats = INT(pi * earth_radius / phys_spacing) |
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149 | IF (MOD(nlats,2)==0) nlats=nlats-1 ! Ensure nlats is odd to have even number around equator. |
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150 | |
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151 | ALLOCATE(tmp_lats(nlats)) |
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152 | |
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153 | lat_step = 180.0_fbdp / (nlats-1) |
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154 | |
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155 | tmp_lats(1) = 0.0_fbdp |
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156 | DO i=1,(nlats-1)/2 |
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157 | tmp_lats(i+1) = tmp_lats(i) + lat_step |
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158 | tmp_lats(((nlats-1)/2)+i+1) = tmp_lats(i+1) * (-1.0_fbdp) |
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159 | END DO |
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160 | |
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161 | k = 0 |
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162 | DO i=1,nlats |
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163 | nlons = INT(2.0_fbdp * pi * earth_radius * cos(tmp_lats(i)* (pi/180.0_fbdp)) / phys_spacing) |
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164 | IF (nlons>0) THEN |
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165 | DO j = 1, nlons |
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166 | k = k + 1 |
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167 | lons(k) = REAL(j-1) * 360.0_fbdp / nlons |
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168 | lats(k) = tmp_lats(i) |
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169 | END DO |
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170 | END IF |
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171 | END DO |
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172 | DEALLOCATE(tmp_lats) |
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173 | |
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174 | END SUBROUTINE set_spatial_coords_physpace |
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175 | |
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176 | |
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177 | SUBROUTINE expand_bounds(array, fillval) |
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178 | ! |
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179 | ! Checks if there are three entries and expands bounds. |
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180 | ! |
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181 | IMPLICIT NONE |
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182 | INTEGER :: i, nentries |
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183 | REAL(KIND=fbdp), INTENT(INOUT) :: array(:) |
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184 | REAL(KIND=fbdp), INTENT(IN) :: fillval |
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185 | REAL(KIND=fbdp) :: nsteps, start, step |
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186 | |
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187 | ! Find number of elements given in list |
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188 | nentries = last_element(array, fillval) |
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189 | |
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190 | IF (nentries==3) THEN ! Bounds given |
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191 | nsteps = (array(2) - array(1)) / array(3) |
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192 | IF ((array(2) < array(1)) .AND. (array(3) >= 0.0)) THEN |
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193 | WRITE(*,*) "Error: if upper bound is less than lower bound, step must be negative.", array |
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194 | CALL abort |
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195 | ELSE IF ( NINT(nsteps)+1 > SIZE(array) ) THEN |
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196 | WRITE(*,*) "Error: bounds not compatible with length of array.", array |
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197 | WRITE(*,*) "Error: bounds not compatible with length of array.", nsteps |
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198 | CALL abort |
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199 | END IF |
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200 | start = array(1) |
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201 | step = array(3) |
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202 | DO i=1,NINT(nsteps)+1 |
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203 | array(i) = start + (i-1)*step |
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204 | END DO |
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205 | END IF |
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206 | |
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207 | END SUBROUTINE expand_bounds |
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208 | |
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209 | |
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210 | |
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211 | INTEGER FUNCTION last_element(array,fillval) |
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212 | ! |
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213 | ! Returns index of the last non-fill value element in a list |
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214 | ! Will return 1, even in first element is the FillValue |
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215 | ! |
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216 | IMPLICIT NONE |
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217 | REAL(KIND=fbdp), INTENT(IN) :: array(:), fillval |
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218 | INTEGER :: i |
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219 | |
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220 | last_element = 1 |
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221 | IF (SIZE(array) > 1) THEN |
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222 | DO i=2, SIZE(array) |
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223 | IF (array(i) /= fillval) THEN |
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224 | last_element = i |
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225 | END IF |
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226 | END DO |
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227 | END IF |
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228 | |
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229 | END FUNCTION last_element |
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230 | |
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231 | |
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232 | |
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233 | SUBROUTINE set_depths(array,n,FillVal) |
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234 | IMPLICIT NONE |
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235 | INTEGER :: i |
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236 | INTEGER, INTENT(IN) :: n |
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237 | REAL(KIND=fbdp), INTENT(INOUT) :: array(:) |
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238 | REAL(KIND=fbdp) :: FillVal |
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239 | REAL(KIND=fbdp) :: start, step, nstep |
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240 | ! Top bound not necessarily inclusive - will use start, step and number of obs |
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241 | |
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242 | ! A single non-FillVal value should be replicated n times |
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243 | ! Three non-FillVal values should be used as the start, end, step in conjunction with n |
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244 | ! unless n is three, in which case treat as list, not bounds. |
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245 | ! A full list of n non-FillVals should be left unaltered. |
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246 | IF (n==1) THEN |
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247 | array(:) = array(1) |
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248 | ELSE IF ((n > 1) .AND. (array(2)==FillVal)) THEN |
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249 | array(:) = array(1) |
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250 | ELSE IF ((n==2) .AND. (array(2)/=FillVal)) THEN |
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251 | array(:) = array(:) |
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252 | ELSE IF (n==3) THEN ! Treat as list of three, not bounds |
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253 | array(:) = array(:) |
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254 | ELSE IF ((n>=4) .AND. (array(4)==FillVal)) THEN ! Assume start, stop, step |
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255 | nstep = (array(2) - array(1)) / array(3) |
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256 | IF ((array(2) < array(1)) .AND. (array(3) >= 0.0)) THEN |
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257 | WRITE(*,*) "Error: if upper bound is less than lower bound, step must be negative.", array |
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258 | CALL abort |
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259 | ELSE IF ( ( nstep < (0.99 * real(n-1)) ) .OR. & |
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260 | ( nstep > (1.01 * real(n-1)) ) ) THEN |
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261 | WRITE(*,*) "Error: depth bounds not compatible.", array |
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262 | WRITE(*,*) "Error: depth bounds not compatible.", nstep |
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263 | CALL abort |
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264 | END IF |
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265 | start = array(1) |
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266 | step = array(3) |
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267 | DO i=1,n |
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268 | array(i) = start + (i-1)*step |
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269 | END DO |
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270 | END IF |
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271 | |
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272 | END SUBROUTINE set_depths |
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273 | |
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274 | |
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275 | |
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276 | |
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277 | |
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278 | SUBROUTINE set_datetime(date,time,julian_date,n,FillVal) |
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279 | ! |
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280 | ! Transform input array from m values describing n dates to a list of n dates. |
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281 | ! |
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282 | IMPLICIT NONE |
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283 | INTEGER :: i |
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284 | INTEGER, INTENT(IN) :: n |
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285 | INTEGER, INTENT(INOUT) :: date(:), time(:) |
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286 | INTEGER :: FillVal |
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287 | REAL(KIND=fbdp), INTENT(INOUT) :: julian_date(:) |
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288 | REAL(KIND=fbdp) :: start, step, finish |
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289 | |
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290 | ! Check if user has supplied start and end times to be split amongst number of obs |
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291 | ! (i.e. more than 2 obs, but only 2 dates and 2 times given.) |
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292 | IF ((n>2) .AND. (date(2)/=FillVal) .AND. (date(3)==FillVal) & |
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293 | & .AND. (time(2)/=FillVal) .AND. (time(3)==FillVal)) THEN |
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294 | |
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295 | !work out JD of each |
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296 | start = fb_dates(time(1),date(1)) |
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297 | finish = fb_dates(time(2),date(2)) |
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298 | |
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299 | ! use info to calc step |
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300 | step = ( finish - start ) / n |
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301 | ! calc all JDs and put output in dates |
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302 | DO i=1,n |
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303 | ! Could make this an elemental function if dateutils were pure funcs |
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304 | julian_date(i)= start + (i-1)*step |
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305 | END DO |
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306 | |
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307 | ELSE |
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308 | CALL set_date(date,n,FillVal) |
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309 | CALL set_time(time,n,FillVal) |
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310 | ! Replace dates with JD including time info |
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311 | DO i=1,n |
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312 | ! Could make this an elemental function if dateutils were pure funcs |
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313 | julian_date(i)= fb_dates(time(i),date(i)) |
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314 | END DO |
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315 | END IF |
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316 | |
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317 | |
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318 | END SUBROUTINE set_datetime |
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319 | |
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320 | |
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321 | SUBROUTINE set_date(array,n,FillVal) |
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322 | ! |
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323 | ! Transform input array from m values describing n dates to a list of n dates. |
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324 | ! |
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325 | IMPLICIT NONE |
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326 | INTEGER :: i |
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327 | INTEGER, INTENT(IN) :: n |
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328 | INTEGER, INTENT(INOUT) :: array(:) |
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329 | INTEGER :: FillVal |
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330 | INTEGER :: start, step, diff |
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331 | ! Top bound not necessarily inclusive - will use start, step and number of obs |
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332 | |
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333 | ! A single non-FillVal value should be replicated n times |
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334 | ! Three non-FillVal values should be used as the start, end, step in conjunction with n |
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335 | ! unless n is three, in which case treat as list, not bounds. |
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336 | ! A full list of n non-FillVals should be left unaltered. |
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337 | IF (n==1) THEN |
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338 | array(:) = array(1) |
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339 | ELSE IF ((n > 1) .AND. (array(2)==FillVal)) THEN |
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340 | array(:) = array(1) |
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341 | ELSE IF ((n==2) .AND. (array(2)/=FillVal)) THEN |
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342 | array(:) = array(:) |
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343 | ELSE IF (n==3) THEN ! Treat as list of three, not bounds |
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344 | array(:) = array(:) |
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345 | ELSE IF ((n>=4) .AND. (array(4)==FillVal)) THEN ! Assume start, stop, step |
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346 | diff = diffdate(array(2),array(1)) ! in number of days |
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347 | IF ((array(2) < array(1)) .AND. (array(3) >= 0)) THEN |
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348 | WRITE(*,*) "Error: if upper bound is less than lower bound, step must be negative.", array |
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349 | CALL abort |
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350 | ELSE IF ( ( diff / ABS(array(3)) ) /= (n-1) ) THEN |
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351 | WRITE(*,*) "Error: date bounds not compatible.", array |
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352 | CALL abort |
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353 | END IF |
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354 | start = array(1) |
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355 | step = array(3) |
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356 | DO i=1,n |
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357 | CALL add_days_to_date(start,(i-1)*step,array(i)) |
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358 | END DO |
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359 | END IF |
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360 | |
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361 | END SUBROUTINE set_date |
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362 | |
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363 | |
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364 | |
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365 | SUBROUTINE set_time(array,n,FillVal) |
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366 | ! |
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367 | ! Transform input array from m (m<=n) values describing n times to a list of n times. |
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368 | ! |
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369 | IMPLICIT NONE |
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370 | INTEGER :: i |
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371 | INTEGER, INTENT(IN) :: n |
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372 | INTEGER, INTENT(INOUT) :: array(:) |
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373 | INTEGER :: FillVal |
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374 | INTEGER :: start, step, nstep |
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375 | ! Top bound not necessarily inclusive - will use start, step and number of obs |
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376 | |
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377 | ! A single non-FillVal value should be replicated n times |
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378 | ! Three non-FillVal values should be used as the start, end, step in conjunction with n |
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379 | ! unless n is three, in which case treat as list, not bounds. |
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380 | ! A full list of n non-FillVals should be left unaltered. |
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381 | IF (n==1) THEN |
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382 | array(:) = array(1) |
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383 | ELSE IF ((n > 1) .AND. (array(2)==FillVal)) THEN |
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384 | array(:) = array(1) |
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385 | ELSE IF ((n==2) .AND. (array(2)/=FillVal)) THEN |
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386 | array(:) = array(:) |
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387 | ELSE IF (n==3) THEN ! Treat as list of three, not bounds |
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388 | array(:) = array(:) |
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389 | ELSE IF ((n>=4) .AND. (array(4)==FillVal)) THEN ! Assume start, stop, step |
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390 | IF (array(3)<0) nstep = difftime(array(2),array(1)) / ABS(array(3)) |
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391 | IF (array(3)>=0) nstep = difftime(array(1),array(2)) / ABS(array(3)) |
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392 | IF ( nstep /= (n-1) ) THEN |
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393 | WRITE(*,*) "Error: time bounds not compatible.", array |
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394 | CALL abort |
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395 | END IF |
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396 | start = array(1) |
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397 | step = array(3) |
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398 | DO i=1,n |
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399 | array(i) = add_mins_to_time(start,(i-1)*step) |
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400 | END DO |
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401 | END IF |
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402 | |
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403 | END SUBROUTINE set_time |
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404 | |
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405 | |
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406 | |
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407 | SUBROUTINE set_obs_values(array,p,n,m,FillVal) |
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408 | ! |
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409 | ! n profiles at m depths |
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410 | ! |
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411 | IMPLICIT NONE |
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412 | INTEGER :: i, j, k |
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413 | INTEGER, INTENT(IN) :: n, m, p |
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414 | REAL(KIND=fbdp), INTENT(INOUT) :: array(:,:,:) ! (nlevels, nprofiles, nvars) = (m,n,p) |
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415 | REAL(KIND=fbdp) :: FillVal |
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416 | |
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417 | |
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418 | DO k=1,p |
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419 | IF ((k > 1) .AND. (array(1,1,k) == FillVal)) THEN ! set to same values as first variable |
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420 | array(:,:,k) = array(:,:,1) |
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421 | ELSE |
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422 | IF ((n==1).AND.(m==1)) THEN |
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423 | array(:,:,k) = array(1,1,k) |
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424 | |
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425 | ! If mult depths, but not specified, set all to one value |
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426 | ELSE IF ((m > 1) .AND. (array(2,1,k) == FillVal)) THEN |
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427 | array(:,:,k) = array(1,1,k) |
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428 | |
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429 | ! If mult profiles and mult depths and only one value set in first profile |
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430 | ELSE IF ((n > 1) .AND. (m > 1) .AND. (array(2,1,k) == FillVal)) THEN |
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431 | array(:,:,k) = array(1,1,k) |
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432 | |
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433 | ! If mult profiles and mult depths and only one first profile set |
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434 | ELSE IF ((n > 1) .AND. (m > 1) .AND. (array(1,2,k) == FillVal)) THEN |
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435 | DO j=1,m |
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436 | array(j,:,k) = array(j,1,k) |
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437 | END DO |
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438 | |
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439 | ELSE |
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440 | array(:,:,k) = array(:,:,k) |
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441 | END IF |
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442 | END IF |
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443 | END DO |
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444 | |
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445 | END SUBROUTINE set_obs_values |
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446 | |
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447 | |
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448 | ! Unbiased shuffle of array |
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449 | SUBROUTINE shuffle(a) |
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450 | REAL(KIND=fbdp), INTENT(INOUT) :: a(:) |
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451 | INTEGER :: i, randpos |
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452 | REAL(KIND=fbdp) :: r, temp |
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453 | |
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454 | CALL random_seed() |
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455 | DO i = SIZE(a), 2, -1 |
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456 | CALL random_number(r) |
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457 | randpos = int(r * i) + 1 |
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458 | temp = a(randpos) |
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459 | a(randpos) = a(i) |
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460 | a(i) = temp |
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461 | END DO |
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462 | |
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463 | END SUBROUTINE shuffle |
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464 | |
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465 | |
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466 | ! Add a random perturbation to the lats and lons |
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467 | ! Perturbation is sampled from a uniform distribution +/-perturb_limit |
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468 | SUBROUTINE perturb_positions(lats,lons,perturb_limit) |
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469 | INTEGER :: i |
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470 | REAL(KIND=fbdp), INTENT(INOUT) :: lats(:), lons(:) |
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471 | REAL(KIND=fbdp), INTENT(IN) :: perturb_limit |
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472 | REAL(KIND=fbdp) :: randpos, lat_perturb, lon_perturb |
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473 | REAL(KIND=fbdp), PARAMETER :: earth_radius = 6371.0_fbdp |
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474 | REAL(KIND=fbdp), PARAMETER :: pi = 3.141592654_fbdp |
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475 | |
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476 | IF ( SIZE(lats) /= SIZE(lons) ) THEN |
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477 | WRITE(*,*) "Error: different number of lat and lon elements", SIZE(lats), SIZE(lons) |
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478 | CALL abort |
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479 | END IF |
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480 | |
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481 | CALL random_seed() |
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482 | |
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483 | ! Convert physical sep into a latidue sep in degrees |
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484 | lat_perturb = 360.0_fbdp * perturb_limit / (2.0_fbdp * pi * earth_radius) |
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485 | |
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486 | DO i=1,SIZE(lats) |
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487 | |
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488 | ! Perturb lats first, as lon conversion uses lat |
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489 | CALL random_number(randpos) |
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490 | lats(i) = lats(i) + randpos*lat_perturb |
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491 | IF (lats(i) > 90.0_fbdp) lats(i) = 180.0_fbdp - lats(i) |
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492 | IF (lats(i) < -90.0_fbdp) lats(i) = (lats(i) + 180.0_fbdp) * (-1.0_fbdp) |
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493 | |
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494 | ! Use lat to convert physical size to delta_longitude |
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495 | IF (ABS(lats(i)) == 90.0_fbdp) THEN |
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496 | lon_perturb = 0.0_fbdp |
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497 | ELSE |
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498 | lon_perturb = 360.0_fbdp * perturb_limit / (2.0_fbdp * pi * earth_radius * cos(lats(i)*(pi/180.0_fbdp))) |
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499 | END IF |
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500 | CALL random_number(randpos) |
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501 | lons(i) = lons(i) + randpos*lon_perturb |
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502 | IF (lons(i) >= 360.0_fbdp) lons(i) = lons(i) - 360.0_fbdp |
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503 | IF (lons(i) < 0.0_fbdp) lons(i) = lons(i) + 360.0_fbdp |
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504 | |
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505 | END DO |
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506 | |
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507 | END SUBROUTINE perturb_positions |
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508 | |
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509 | END MODULE fbgenerate_coords |
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