Hi, today i wrote a function in R of the type: index.refraction <- function(Temp,Press, RH, CO2) When i try to plug a negative number in Temp, i got this type of error: " n <- index.refraction(Temp= -40,100,80,CO2) Messages d'avis : 1: In Ops.ordered(left, right) : '-' is not meaningful for ordered factors 2: In Ops.factor(left, right) : - not meaningful for factors 3: In Ops.factor(left, right) : - not meaningful for factors 4: In Ops.ordered(left, right) : '-' is not meaningful for ordered factors 5: In Ops.factor(left, right) : - not meaningful for factors 6: In Ops.factor(left, right) : - not meaningful for factors " Do you have any idea what can be the reason? Thanks Simon -- View this message in context: http://r.789695.n4.nabble.com/Cannot-use-negative-argument-in-function-tp4430667p4430667.html Sent from the R help mailing list archive at Nabble.com.
On 29-02-2012, at 07:03, lidaky wrote:> Hi, > > today i wrote a function in R of the type: > > index.refraction <- function(Temp,Press, RH, CO2) > > When i try to plug a negative number in Temp, i got this type of error: > > " > n <- index.refraction(Temp= -40,100,80,CO2) > Messages d'avis : > 1: In Ops.ordered(left, right) : '-' is not meaningful for ordered factors > 2: In Ops.factor(left, right) : - not meaningful for factors > 3: In Ops.factor(left, right) : - not meaningful for factors > 4: In Ops.ordered(left, right) : '-' is not meaningful for ordered factors > 5: In Ops.factor(left, right) : - not meaningful for factors > 6: In Ops.factor(left, right) : - not meaningful for factors > "Without the code of your function we can only guess. Please follow the posting guide. Berend
Do an str() on the data. It looks like temp is a factor and I doubt that factors can be negative. John Kane Kingston ON Canada> -----Original Message----- > From: svfilhol at alaska.edu > Sent: Tue, 28 Feb 2012 22:03:19 -0800 (PST) > To: r-help at r-project.org > Subject: [R] Cannot use negative argument in function > > Hi, > > today i wrote a function in R of the type: > > index.refraction <- function(Temp,Press, RH, CO2) > > When i try to plug a negative number in Temp, i got this type of error: > > " > n <- index.refraction(Temp= -40,100,80,CO2) > Messages d'avis : > 1: In Ops.ordered(left, right) : '-' is not meaningful for ordered > factors > 2: In Ops.factor(left, right) : - not meaningful for factors > 3: In Ops.factor(left, right) : - not meaningful for factors > 4: In Ops.ordered(left, right) : '-' is not meaningful for ordered > factors > 5: In Ops.factor(left, right) : - not meaningful for factors > 6: In Ops.factor(left, right) : - not meaningful for factors > " > > Do you have any idea what can be the reason? > Thanks > Simon > > -- > View this message in context: > http://r.789695.n4.nabble.com/Cannot-use-negative-argument-in-function-tp4430667p4430667.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.____________________________________________________________ FREE ONLINE PHOTOSHARING - Share your photos online with your friends and family! Visit http://www.inbox.com/photosharing to find out more!
here is the code:
index.refraction <- function(Temp,Press, RH, CO2)
{
#define constant
lambda <- 531 #nm
Co <- 299792458 #m/s
ww <- c(295.235,2.6422,-0.03238,0.004028)
kk <- c( 238.0185 ,5792105 ,57.362 ,167917)
aa <- c( 1.58123 * 10^(-6) , -2.9331 * 10^(-8) , 1.1043 * 10^(-10))
bb <- c( 5.707 * 10^(-6) , -2.051 * 10^(-8))
cc <- c(1.9898 * 10^(-4) , -2.376 * 10^(-6))
dd <- 1.83 * 10^(-11)
ee <- -0.765 * 10^(-8)
pp <- 101325
tt <- 288.15
zz <- 0.9995922115
ro <- 0.00985938
R <- 8.314472
M <- 0.018015
S <- 1/(lambda*10^-3)^2
ras <- 10^-8*((kk[2]/(kk[1]-S))+(kk[4]/(kk[3]-S)))
rvs <- 1.022*10^-8*(ww[1]+S*ww[2]+ww[3]*S^2+ww[4]*S^3)
Ma <- 0.0289635 + 1.2011 * 10^(-8) * (CO2 - 400)
raxs <- ras*(1+5.34*10^-7*(CO2-450))
TT <- *Temp*+273.15
#Saturation vapor pressure over ice
# A1 <- -13.928169
# A2 <- 34.7078238
# Theta <- (*Temp*+273.15)/273.16
# Y <- A1 * (1 - Theta^(-1.5)) + A2 * (1 - Theta^(-1.25))
# Psv <- 611.657*exp(Y)
#Saturation vapor pressure over water
Tc <- 647.096 # K : Temperature at the critical point
Pc <- 22.064 * 10^4 # hPa : Vapor pressure at the critical point
nu <- (1-TT/Tc)
a1 <- -7.85951783
a2 <- 1.84408259
a3 <- -11.7866497
a4 <- 22.6807411
a5 <- -15.9618719
a6 <- 1.80122502
Psv <- Pc * exp(Tc/TT * (a1*nu + a2*nu^1.5 + a3*nu^3. + a4*nu^3.5 +
a5*nu^4. + a6*nu^7.5))
Alpha <- 1.00062
Beta <- 3.14 * 10^(-8)
Gamma <- 5.60 * 10^(-7)
fpt <- Alpha+Beta*Press+Gamma**Temp*^2
Xv <- (RH/100)*fpt*Psv/Press
Zm <- 1-(Press/TT)*(aa[1]+aa[2]**Temp*+aa[3]**Temp*^2
+(bb[1]+bb[2]*Temp)*Xv+(cc[1]+cc[2]**Temp*)*Xv^2)
+(Press/TT)^2*(dd+ee*Xv^2)
Roaxs <- pp*Ma/(zz*R*tt)
Rov <- Xv*Press*M/(Zm*R*TT)
Roa <- (1-Xv)*Press*Ma/(Zm*R*TT)
n <- 1+(Roa/Roaxs)*raxs+(Rov/ro)*rvs
return(n)
}
Basically, this is just a function to calculate index of refraction in air.
The function is just dealing with numbers.
So i am quite surprise getting this error.
Simon
--
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