PE_Oudin.R 4.87 KB
Newer Older
1
PE_Oudin <- function(JD, Temp,
2
                     Lat, LatUnit = c("rad", "deg"),
3
4
                     TimeStepIn = "daily", TimeStepOut = "daily",
                     RunFortran = F) {
5
6
7
8
  
  
  ## ---------- check arguments
  
9
10
11
12
13
14
  # if (!missing(LatRad)) {
  #   warning("Deprecated 'LatRad' argument. Please, use 'Lat' instead.")
  #   if (missing(Lat)) {
  #     Lat <- LatRad
  #   }
  # }
15
16
17
18
19
20
21
  if (!(inherits(JD, "numeric") | inherits(JD, "integer"))) {
    stop("'JD' must be of class 'numeric'")
  }
  if (!(inherits(Temp, "numeric") | inherits(Temp, "integer"))) {
    stop("'Temp' must be of class 'numeric'")
  }
  if (length(JD) != length(Temp)) {
22
    stop("'JD' and 'Temp' must have the same length")
23
  }
24
25

  if (!RunFortran & (!inherits(Lat, "numeric") | length(Lat) != 1)) {
26
27
    stop("'Lat' must be a 'numeric' of length one")
  }
28
29
30
31
32
  if (RunFortran & (!inherits(Lat, "numeric") | (!length(Lat) %in% c(1, length(Temp))))) {
    stop("'Lat' must be a 'numeric' of length one or of the same length as 'Temp'")
  }
  LatUnit <- match.arg(LatUnit, choices = c("rad", "deg"))
  if (LatUnit[1L] == "rad" & (all(Lat >= pi/2) | all(Lat <= -pi/2))) {
33
34
    stop("'Lat' must be comprised between -pi/2 and +pi/2 degrees")
  }
35
  if (LatUnit[1L] == "deg" & (all(Lat >= 90) | all(Lat <= -90))) {
36
37
    stop("'Lat' must be  comprised between -90 and +90 degrees")
  }
38
  if (!RunFortran & LatUnit[1L] == "rad") {
39
40
    FI <- Lat
  }
41
  if (!RunFortran & LatUnit[1L] == "deg") {
42
43
44
45
46
    FI <- Lat / (180 / pi)
  }
  if (any(JD < 0) | any(JD > 366)) {
    stop("'JD' must only contain integers from 1 to 366")
  }
47
48
49
  TimeStep <- c("daily", "hourly")
  TimeStepIn  <- match.arg(TimeStepIn , choices = TimeStep)
  TimeStepOut <- match.arg(TimeStepOut, choices = TimeStep)
50
51
52
53
54
55
  rleJD <- rle(JD)
  if (TimeStepIn == "daily" & any(rleJD$lengths != 1)) {
    stop("each day must have only one identical value of julian days")
  }
  if (TimeStepIn == "hourly" & any(rleJD$lengths != 24)) {
    stop("each day must have 24 identical values of julian days (one for each hour)")
56
  }
57
58
59
60
61
62
63
64
65
66
67
68
69
  
  
  ## ---------- hourly inputs aggregation
  
  if (TimeStepIn == "hourly") {
    JD <- rleJD$values
    idJD <- rep(seq_along(JD), each = rleJD$lengths[1L])
    Temp <- as.vector(tapply(X = Temp, INDEX = idJD, FUN = mean))
  }
  
  
  ## ---------- Oudin's formula
  
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
  if (RunFortran)
  {
    if (LatUnit[1L] == "rad") {
      Lat = Lat * 180 / pi
    }
    
    LInputs = as.integer(length(Temp))
    
    if (length(Lat) == 1) {
      Lat = rep(Lat, LInputs)
    }
    
    RESULTS <- .Fortran("frun_etp_oudin", PACKAGE="airGR",
                        ##inputs
                        LInputs = LInputs,
                        InputsLAT = as.double(Lat),
                        InputsTT = as.double(Temp),
                        InputsJJ = as.double(JD),
                        ##outputs                                                               
                        PE_Oudin_D = rep(as.double(-999.999), LInputs)
    )
    PE_Oudin_D = RESULTS$PE_Oudin_D
    
  } else {
    
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
  PE_Oudin_D <- rep(NA, length(Temp))
  COSFI <- cos(FI)
  AFI <- abs(FI / 42) 
  
  for (k in seq_along(Temp)) {
    
    TETA <- 0.4093 * sin(JD[k] / 58.1 - 1.405)
    COSTETA <- cos(TETA)
    COSGZ <- max(0.001, cos(FI - TETA))
    GZ <- acos(COSGZ)
    COSOM <- 1 - COSGZ / COSFI / COSTETA
    
    if (COSOM < -1) {
      COSOM <- -1
    }
    if (COSOM > 1) {
      COSOM <-  1
    }
    
    COSOM2 <- COSOM * COSOM
    
    if (COSOM2 >= 1) {
      SINOM <- 0
    } else {
      SINOM <- sqrt(1 - COSOM2)
    }
    
    OM <- acos(COSOM)
    COSPZ <- COSGZ + COSFI * COSTETA * (SINOM/OM - 1)
    
    if (COSPZ < 0.001) {
      COSPZ <- 0.001
    }
    
    ETA <- 1 + cos(JD[k] / 58.1) / 30
    GE <- 446 * OM * COSPZ * ETA
    
    if (is.na(Temp[k])) {
      PE_Oudin_D[k] <- NA
    } else {
      if (Temp[k] >= -5.0) {
        PE_Oudin_D[k] <- GE * (Temp[k] + 5) / 100 / 28.5
      } else {
        PE_Oudin_D[k] <- 0
      }
    }
    
  }
  
144
  }
145
146
147
148
  
  ## ---------- disaggregate PE from daily to hourly
  
  if (TimeStepOut == "hourly") {
149
    parab_D2H <- c(0.000, 0.000, 0.000, 0.000, 0.000, 0.000,
150
151
                   0.035, 0.062, 0.079, 0.097, 0.110, 0.117,
                   0.117, 0.110, 0.097, 0.079, 0.062, 0.035,
152
                   0.000, 0.000, 0.000, 0.000, 0.000, 0.000)
153
    PE_Oudin_H <- rep(PE_Oudin_D, each = 24) * rep(parab_D2H, times = length(PE_Oudin_D))
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
  }
  
  
  ## ---------- outputs warnings
  
  if (any(is.na(Temp))) {
    if (any(is.na(PE_Oudin_D))) {
      warning("'Temp' time series, and therefore the returned 'PE' time series, contain missing value(s)")
    } else {
      warning("'Temp' time series contains missing value(s)")
    }
  }
  if (!any(is.na(Temp)) & any(is.na(PE_Oudin_D))) {
    warning("returned 'PE' time series contains missing value(s)")
  }
  
  if (TimeStepOut == "daily") {
    PE_Oudin <- PE_Oudin_D
  } else {
    PE_Oudin <- PE_Oudin_H
  }
  return(PE_Oudin)
  
}