wcm_sim {WCM}

Simulate backscattering coefficient using WCM model

Description

This function can be used to simulate the backscattering coefficient using WCM. This function can be called in nls function for generation of model coefficients (A,B,C,D).

Usage

wcm_sim(X, Y, theta, A, B, C, D)

Arguments

X

In situ LAI or vegetation descriptor

Y

In situ SM soil moisture

theta

incident angle of Satellite sensor

A

fitted coefficient for WCM using non linear least squre using in situ data

B

fitted coefficient for WCM using non linear least squre using in situ data

C

fitted coefficient for WCM using non linear least squre using in situ data

D

fitted coefficient for WCM using non linear least squre using in situ data

wcm_sim

is simulated backscattering coefficient

Value

simulated backscattering coefficient

Examples

# For single value.
 n <- wcm_sim(4,.3,48.9,-9.596695,-0.005331,-11.758309,0.011344)

#For list of value
X<-c(5.34, 4.34, 4.32, 4.12, 4.17, 3.58, 5.39, 5.66, 5.47, 5.73, 5.76, 5.93, 4.91, 5.36, 6.15,
     4.56, 5.44, 6.54, 6.20, 6.34, 5.56, 5.88, 7.34, 5.74, 4.81, 5.73, 3.63, 4.61, 4.76, 4.02)
Y<-c(35.0, 26.0, 18.0, 13.0, 18.0, 22.0, 19.0, 16.5, 20.0, 24.0, 24.0, 21.0, 13.0, 22.0, 25.0,
     24.0, 30.0, 23.0, 18.0, 17.6, 15.0, 17.0, 27.0, 22.0, 21.0, 15.0, 15.0, 18.0, 31.0, 10.0)

w<-c(-9.604, -11.648, -11.556, -11.556, -11.090, -10.444, -10.444, -10.042,  -9.200,  -9.750,
       -9.200,  -9.200,  -9.812,  -9.972,  -8.938,  -9.200,  -8.198,  -7.722,  -7.348,  -7.348,
       -8.198, -10.082,  -6.870,  -8.104,  -8.732,  -7.830, -10.686, -10.964, -10.976, -10.976)

theta<-48.9
example(nlc<-nls.control(maxiter = 50000, tol = 1e-05, minFactor = 1/100000000000,
printEval = FALSE, warnOnly = FALSE))
example(k<-nls(w~wcm_sim(X,Y,theta,A,B,C,D),control=nlc,
 start=list(A= 0.01,B=0.01,C=-21,D= 0.00014),trace = T))
example(y<-predict(k))
n <- wcm_sim(X,Y,theta,-9.596695,-0.005331,-11.758309,0.011344)