update ffmc coefficient as per email 'If you want the EXACT number it…

…s 250.0*59.5/101.0'

R/Slopecalc.r

@@ -295,7 +295,7 @@ slope_adjustment <- function(
     },
     {
   # Eq. 46 (FCFDG 1992)
-  m <- 147.27723 * (101 - FFMC) / (59.5 + FFMC)
+  m <- FFMC_COEFFICIENT * (101 - FFMC) / (59.5 + FFMC)
   # Eq. 45 (FCFDG 1992) - FFMC function from the ISI equation
   fF <- 91.9 * exp(-.1386 * m) * (1 + (m**5.31) / 4.93e7)
   # Eqs. 44a, 44d (Wotton 2009) - Slope equivalent wind speed

R/back_rate_of_spread.r

@@ -27,7 +27,7 @@ back_rate_of_spread <- function(
     FMC, SFC, PC, PDF, CC, CBH) {
   # Eq. 46 (FCFDG 1992)
   # Calculate the FFMC function from the ISI equation
-  m <- 147.27723 * (101 - FFMC) / (59.5 + FFMC)
+  m <- FFMC_COEFFICIENT * (101 - FFMC) / (59.5 + FFMC)
   # Eq. 45 (FCFDG 1992)
   fF <- 91.9 * exp(-0.1386 * m) * (1.0 + (m**5.31) / 4.93e7)
   # Eq. 75 (FCFDG 1992)

R/fine_fuel_moisture_code.r

@@ -1,3 +1,6 @@
+# used in conversion between FFMC and moisture content
+FFMC_COEFFICIENT <- 250.0 * 59.5 / 101.0
+
 #' Fine Fuel Moisture Code Calculation
 #'
 #' @description Fine Fuel Moisture Code Calculation. All code is based on a C
@@ -26,7 +29,7 @@
 
 fine_fuel_moisture_code <- function(ffmc_yda, temp, rh, ws, prec) {
   # Eq. 1
-  wmo <- 147.27723 * (101 - ffmc_yda) / (59.5 + ffmc_yda)
+  wmo <- FFMC_COEFFICIENT * (101 - ffmc_yda) / (59.5 + ffmc_yda)
   # Eq. 2 Rain reduction to allow for loss in
   #  overhead canopy
   ra <- ifelse(prec > 0.5, prec - 0.5, prec)
@@ -73,7 +76,7 @@ fine_fuel_moisture_code <- function(ffmc_yda, temp, rh, ws, prec) {
   # Eq. 9
   wm <- ifelse(wmo > ed, ed + (wmo - ed) / (10^x), wm)
   # Eq. 10 Final ffmc calculation
-  ffmc1 <- (59.5 * (250 - wm)) / (147.27723 + wm)
+  ffmc1 <- (59.5 * (250 - wm)) / (FFMC_COEFFICIENT + wm)
   # Constraints
   ffmc1 <- ifelse(ffmc1 > 101, 101, ffmc1)
   ffmc1 <- ifelse(ffmc1 < 0, 0, ffmc1)

R/grass_fuel_moisture.r

@@ -18,7 +18,7 @@ grass_fuel_moisture <- function(
     temp, rh, ws, prec,
     isol, GFMCold, roFL=0.3, time.step=1) {
   # Eq. 13 - Calculate previous moisture code
-  MCold <- 147.27723 * ((101 - GFMCold) / (59.5 + GFMCold))
+  MCold <- FFMC_COEFFICIENT * ((101 - GFMCold) / (59.5 + GFMCold))
   # Eq. 11 - Calculate the moisture content of the layer in % after rainfall
   MCr <- ifelse(prec > 0, MCold + 100 * (prec / roFL), MCold)
   # Constrain to 250

R/grass_fuel_moisture_code.r

@@ -12,6 +12,6 @@
 
 grass_fuel_moisture_code <- function(MC0) {
   # Eq. 12 - Calculate GFMC
-  GFMC0 <- 59.5 * ((250 - MC0) / (147.27723 + MC0))
+  GFMC0 <- 59.5 * ((250 - MC0) / (FFMC_COEFFICIENT + MC0))
   return(GFMC0)
 }

R/hourly_fine_fuel_moisture_code.r

@@ -165,7 +165,7 @@
 
 hourly_fine_fuel_moisture_code <- function(temp, rh, ws, prec, Fo, t0) {
   # Eq. 1 (with a more precise multiplier than the daily)
-  mo <- 147.27723 * (101 - Fo) / (59.5 + Fo)
+  mo <- FFMC_COEFFICIENT * (101 - Fo) / (59.5 + Fo)
   rf <- prec
   # Eqs. 3a & 3b (Van Wagner & Pickett 1985)
   mr <- ifelse(
@@ -201,8 +201,8 @@ hourly_fine_fuel_moisture_code <- function(temp, rh, ws, prec, Fo, t0) {
   # Constraints
   m <- ifelse(mo > Ed, md, mw)
   m <- ifelse(Ed >= mo & mo >= Ew, mo, m)
-  # Eq. 6 - Final hffmc calculation (modified 3rd constant to 147.27723)
-  Fo <- 59.5 * (250 - m) / (147.27723 + m)
+  # Eq. 6 - Final hffmc calculation
+  Fo <- 59.5 * (250 - m) / (FFMC_COEFFICIENT + m)
   Fo <- ifelse(Fo <= 0, 0, Fo)
   return(Fo)
 }

R/initial_spread_index.r

@@ -27,7 +27,7 @@ initial_spread_index <- function(
     ws,
     fbpMod = FALSE) {
   # Eq. 10 - Moisture content
-  fm <- 147.27723 * (101 - ffmc) / (59.5 + ffmc)
+  fm <- FFMC_COEFFICIENT * (101 - ffmc) / (59.5 + ffmc)
   # Eq. 24 - Wind Effect
   # the ifelse, also takes care of the ISI modification for the fbp functions
   # This modification is Equation 53a in FCFDG (1992)

tests/testthat/data/BackRateOfSpread.csv

@@ -490,7 +490,7 @@ C6,25.8,218.7,-10,437.4,19683,0,54,27,0,7.675e-11
 M3,47.7,0,427.4,437.4,19683,0,54,27,0,4.969e-15
 M4,67.2,874.8,-10,0,0,27,54,27,0,0.5239
 O1B,89.1,656.1,427.4,0,0,27,54,27,0,2.101e-17
-C1,10.2,656.1,208.7,218.7,0,27,54,27,0,6.548e-51
+C1,10.2,656.1,208.7,218.7,0,27,54,27,0,6.549e-51
 C6,32.1,437.4,-10,437.4,0,27,54,27,0,NA
 M3,54,218.7,427.4,437.4,0,27,54,27,0,1.652e-14
 O1A,75.9,0,208.7,0,6561,27,54,27,0,9.197e-09
@@ -1428,7 +1428,7 @@ C6,25.8,218.7,-10,437.4,19683,0,54,0,72.9,7.675e-11
 M3,47.7,0,427.4,437.4,19683,0,54,0,72.9,4.969e-15
 M4,67.2,874.8,-10,0,0,27,54,0,72.9,0.5239
 O1B,89.1,656.1,427.4,0,0,27,54,0,72.9,1e-06
-C1,10.2,656.1,208.7,218.7,0,27,54,0,72.9,6.548e-51
+C1,10.2,656.1,208.7,218.7,0,27,54,0,72.9,6.549e-51
 C6,32.1,437.4,-10,437.4,0,27,54,0,72.9,1.737e-08
 M3,54,218.7,427.4,437.4,0,27,54,0,72.9,1.652e-14
 O1A,75.9,0,208.7,0,6561,27,54,0,72.9,1e-06
@@ -2366,7 +2366,7 @@ C6,25.8,218.7,-10,437.4,19683,0,54,81,72.9,7.675e-11
 M3,47.7,0,427.4,437.4,19683,0,54,81,72.9,4.969e-15
 M4,67.2,874.8,-10,0,0,27,54,81,72.9,0.5239
 O1B,89.1,656.1,427.4,0,0,27,54,81,72.9,6.216e-16
-C1,10.2,656.1,208.7,218.7,0,27,54,81,72.9,6.548e-51
+C1,10.2,656.1,208.7,218.7,0,27,54,81,72.9,6.549e-51
 C6,32.1,437.4,-10,437.4,0,27,54,81,72.9,1.737e-08
 M3,54,218.7,427.4,437.4,0,27,54,81,72.9,1.652e-14
 O1A,75.9,0,208.7,0,6561,27,54,81,72.9,2.721e-07
@@ -3304,7 +3304,7 @@ C6,25.8,218.7,-10,437.4,19683,0,54,54,145.8,7.675e-11
 M3,47.7,0,427.4,437.4,19683,0,54,54,145.8,4.969e-15
 M4,67.2,874.8,-10,0,0,27,54,54,145.8,0.5239
 O1B,89.1,656.1,427.4,0,0,27,54,54,145.8,1.301e-16
-C1,10.2,656.1,208.7,218.7,0,27,54,54,145.8,6.548e-51
+C1,10.2,656.1,208.7,218.7,0,27,54,54,145.8,6.549e-51
 C6,32.1,437.4,-10,437.4,0,27,54,54,145.8,1.737e-08
 M3,54,218.7,427.4,437.4,0,27,54,54,145.8,1.652e-14
 O1A,75.9,0,208.7,0,6561,27,54,54,145.8,5.694e-08

tests/testthat/data/HourlyFineFuelMoistureCode.csv

@@ -2,109 +2,109 @@ temp,rh,ws,prec,ffmc_old,time.step,HourlyFineFuelMoistureCode
 -30,-10,0,-10,0,0,NA
 42.9,-10,0,-10,0,0,NA
 25.7,-2.71,0,-10,0,0,NA
-8.5,4.58,0,-10,0,0,0
--8.7,11.87,0,-10,0,0,0
--25.9,19.16,0,-10,0,0,0
-47,19.16,0,-10,0,0,0
-29.8,26.45,0,-10,0,0,0
-12.6,33.74,0,-10,0,0,0
--4.6,41.03,0,-10,0,0,0
--21.8,48.32,0,-10,0,0,0
-51.1,48.32,0,-10,0,0,0
-33.9,55.61,0,-10,0,0,0
-16.7,62.9,0,-10,0,0,0
--0.5,70.19,0,-10,0,0,0
--17.7,77.48,0,-10,0,0,0
-55.2,77.48,0,-10,0,0,0
-38,84.77,0,-10,0,0,0
-20.8,92.06,0,-10,0,0,0
-3.6,99.35,0,-10,0,0,0
--13.6,106.64,0,-10,0,0,0
-59.3,106.64,0,-10,0,0,0
+8.5,4.58,0,-10,0,0,4.257e-15
+-8.7,11.87,0,-10,0,0,4.257e-15
+-25.9,19.16,0,-10,0,0,4.257e-15
+47,19.16,0,-10,0,0,4.257e-15
+29.8,26.45,0,-10,0,0,4.257e-15
+12.6,33.74,0,-10,0,0,4.257e-15
+-4.6,41.03,0,-10,0,0,4.257e-15
+-21.8,48.32,0,-10,0,0,4.257e-15
+51.1,48.32,0,-10,0,0,4.257e-15
+33.9,55.61,0,-10,0,0,4.257e-15
+16.7,62.9,0,-10,0,0,4.257e-15
+-0.5,70.19,0,-10,0,0,4.257e-15
+-17.7,77.48,0,-10,0,0,4.257e-15
+55.2,77.48,0,-10,0,0,4.257e-15
+38,84.77,0,-10,0,0,4.257e-15
+20.8,92.06,0,-10,0,0,4.257e-15
+3.6,99.35,0,-10,0,0,4.257e-15
+-13.6,106.64,0,-10,0,0,4.257e-15
+59.3,106.64,0,-10,0,0,4.257e-15
 42,-10,72.9,-10,0,0,NA
 24.8,-2.71,72.9,-10,0,0,NA
-7.6,4.58,72.9,-10,0,0,0
--9.6,11.87,72.9,-10,0,0,0
+7.6,4.58,72.9,-10,0,0,4.257e-15
+-9.6,11.87,72.9,-10,0,0,4.257e-15
 -26.8,19.16,72.9,-10,0,0,0
-46.1,19.16,72.9,-10,0,0,0
-28.9,26.45,72.9,-10,0,0,0
-11.7,33.74,72.9,-10,0,0,0
--5.5,41.03,72.9,-10,0,0,0
+46.1,19.16,72.9,-10,0,0,4.257e-15
+28.9,26.45,72.9,-10,0,0,4.257e-15
+11.7,33.74,72.9,-10,0,0,4.257e-15
+-5.5,41.03,72.9,-10,0,0,4.257e-15
 -22.7,48.32,72.9,-10,0,0,0
-50.2,48.32,72.9,-10,0,0,0
-33,55.61,72.9,-10,0,0,0
-15.8,62.9,72.9,-10,0,0,0
--1.4,70.19,72.9,-10,0,0,0
--18.6,77.48,72.9,-10,0,0,0
-54.3,77.48,72.9,-10,0,0,0
-37.1,84.77,72.9,-10,0,0,0
-19.9,92.06,72.9,-10,0,0,0
+50.2,48.32,72.9,-10,0,0,4.257e-15
+33,55.61,72.9,-10,0,0,4.257e-15
+15.8,62.9,72.9,-10,0,0,4.257e-15
+-1.4,70.19,72.9,-10,0,0,8.513e-15
+-18.6,77.48,72.9,-10,0,0,4.257e-15
+54.3,77.48,72.9,-10,0,0,4.257e-15
+37.1,84.77,72.9,-10,0,0,4.257e-15
+19.9,92.06,72.9,-10,0,0,4.257e-15
 2.7,99.35,72.9,-10,0,0,0
--14.5,106.64,72.9,-10,0,0,0
-58.4,106.64,72.9,-10,0,0,0
+-14.5,106.64,72.9,-10,0,0,4.257e-15
+58.4,106.64,72.9,-10,0,0,4.257e-15
 41.1,-10,145.8,-10,0,0,NA
 23.9,-2.71,145.8,-10,0,0,NA
-6.7,4.58,145.8,-10,0,0,0
--10.5,11.87,145.8,-10,0,0,0
--27.7,19.16,145.8,-10,0,0,0
-45.2,19.16,145.8,-10,0,0,0
-28,26.45,145.8,-10,0,0,0
-10.8,33.74,145.8,-10,0,0,0
--6.4,41.03,145.8,-10,0,0,0
--23.6,48.32,145.8,-10,0,0,0
-49.3,48.32,145.8,-10,0,0,0
-32.1,55.61,145.8,-10,0,0,0
-14.9,62.9,145.8,-10,0,0,0
--2.3,70.19,145.8,-10,0,0,0
--19.5,77.48,145.8,-10,0,0,0
-53.4,77.48,145.8,-10,0,0,0
-36.2,84.77,145.8,-10,0,0,0
+6.7,4.58,145.8,-10,0,0,4.257e-15
+-10.5,11.87,145.8,-10,0,0,4.257e-15
+-27.7,19.16,145.8,-10,0,0,4.257e-15
+45.2,19.16,145.8,-10,0,0,4.257e-15
+28,26.45,145.8,-10,0,0,4.257e-15
+10.8,33.74,145.8,-10,0,0,4.257e-15
+-6.4,41.03,145.8,-10,0,0,4.257e-15
+-23.6,48.32,145.8,-10,0,0,4.257e-15
+49.3,48.32,145.8,-10,0,0,4.257e-15
+32.1,55.61,145.8,-10,0,0,4.257e-15
+14.9,62.9,145.8,-10,0,0,4.257e-15
+-2.3,70.19,145.8,-10,0,0,4.257e-15
+-19.5,77.48,145.8,-10,0,0,4.257e-15
+53.4,77.48,145.8,-10,0,0,4.257e-15
+36.2,84.77,145.8,-10,0,0,4.257e-15
 19,92.06,145.8,-10,0,0,0
-1.8,99.35,145.8,-10,0,0,0
--15.4,106.64,145.8,-10,0,0,0
-57.5,106.64,145.8,-10,0,0,0
+1.8,99.35,145.8,-10,0,0,4.257e-15
+-15.4,106.64,145.8,-10,0,0,4.257e-15
+57.5,106.64,145.8,-10,0,0,4.257e-15
 40.2,-10,218.7,-10,0,0,NA
 23,-2.71,218.7,-10,0,0,NA
-5.8,4.58,218.7,-10,0,0,0
--11.4,11.87,218.7,-10,0,0,0
--28.6,19.16,218.7,-10,0,0,0
-44.3,19.16,218.7,-10,0,0,0
-27.1,26.45,218.7,-10,0,0,0
-9.9,33.74,218.7,-10,0,0,0
--7.3,41.03,218.7,-10,0,0,0
--24.5,48.32,218.7,-10,0,0,0
+5.8,4.58,218.7,-10,0,0,4.257e-15
+-11.4,11.87,218.7,-10,0,0,4.257e-15
+-28.6,19.16,218.7,-10,0,0,4.257e-15
+44.3,19.16,218.7,-10,0,0,4.257e-15
+27.1,26.45,218.7,-10,0,0,4.257e-15
+9.9,33.74,218.7,-10,0,0,4.257e-15
+-7.3,41.03,218.7,-10,0,0,8.513e-15
+-24.5,48.32,218.7,-10,0,0,4.257e-15
 48.4,48.32,218.7,-10,0,0,0
-31.2,55.61,218.7,-10,0,0,0
-14,62.9,218.7,-10,0,0,0
+31.2,55.61,218.7,-10,0,0,4.257e-15
+14,62.9,218.7,-10,0,0,8.513e-15
 -3.2,70.19,218.7,-10,0,0,0
--20.4,77.48,218.7,-10,0,0,0
-52.5,77.48,218.7,-10,0,0,0
-35.3,84.77,218.7,-10,0,0,0
-18.1,92.06,218.7,-10,0,0,0
-0.9,99.35,218.7,-10,0,0,0
--16.3,106.64,218.7,-10,0,0,0
+-20.4,77.48,218.7,-10,0,0,4.257e-15
+52.5,77.48,218.7,-10,0,0,4.257e-15
+35.3,84.77,218.7,-10,0,0,4.257e-15
+18.1,92.06,218.7,-10,0,0,4.257e-15
+0.9,99.35,218.7,-10,0,0,4.257e-15
+-16.3,106.64,218.7,-10,0,0,8.513e-15
 56.6,106.64,218.7,-10,0,0,0
 39.3,-10,291.6,-10,0,0,NA
 22.1,-2.71,291.6,-10,0,0,NA
-4.9,4.58,291.6,-10,0,0,0
--12.3,11.87,291.6,-10,0,0,0
--29.5,19.16,291.6,-10,0,0,0
-43.4,19.16,291.6,-10,0,0,0
-26.2,26.45,291.6,-10,0,0,0
-9,33.74,291.6,-10,0,0,0
--8.2,41.03,291.6,-10,0,0,0
--25.4,48.32,291.6,-10,0,0,0
-47.5,48.32,291.6,-10,0,0,0
-30.3,55.61,291.6,-10,0,0,0
-13.1,62.9,291.6,-10,0,0,0
--4.1,70.19,291.6,-10,0,0,0
--21.3,77.48,291.6,-10,0,0,0
-51.6,77.48,291.6,-10,0,0,0
+4.9,4.58,291.6,-10,0,0,4.257e-15
+-12.3,11.87,291.6,-10,0,0,4.257e-15
+-29.5,19.16,291.6,-10,0,0,4.257e-15
+43.4,19.16,291.6,-10,0,0,4.257e-15
+26.2,26.45,291.6,-10,0,0,4.257e-15
+9,33.74,291.6,-10,0,0,8.513e-15
+-8.2,41.03,291.6,-10,0,0,4.257e-15
+-25.4,48.32,291.6,-10,0,0,4.257e-15
+47.5,48.32,291.6,-10,0,0,4.257e-15
+30.3,55.61,291.6,-10,0,0,4.257e-15
+13.1,62.9,291.6,-10,0,0,4.257e-15
+-4.1,70.19,291.6,-10,0,0,4.257e-15
+-21.3,77.48,291.6,-10,0,0,4.257e-15
+51.6,77.48,291.6,-10,0,0,4.257e-15
 34.4,84.77,291.6,-10,0,0,0
-17.2,92.06,291.6,-10,0,0,0
-0,99.35,291.6,-10,0,0,0
--17.2,106.64,291.6,-10,0,0,0
-55.7,106.64,291.6,-10,0,0,0
+17.2,92.06,291.6,-10,0,0,4.257e-15
+0,99.35,291.6,-10,0,0,4.257e-15
+-17.2,106.64,291.6,-10,0,0,4.257e-15
+55.7,106.64,291.6,-10,0,0,4.257e-15
 37.5,-10,0,55.61,0,0,NA
 20.3,-2.71,0,55.61,0,0,NA
 3.1,4.58,0,55.61,0,0,0