Simulate from a distribution function using Rejection Method - r

I am trying to simulate data 10000 observations for the following distribution:
{ 3x(1-x)2 0 < x < 1
f(x) = { 3(2-x)(1-x)2 1 ≤ x < 2
{ 0 otherwise
Using the rejection method, I am boxing the distribution by the following rectangle: x=0,x=2,y=0,y=2
However, there is some fault in my code below as it doesn't seem to work. Can any one please advise on a fix?
n=10000
t=0
x=0
while(t<n)
{u=runif(1,0,2)
y=runif(1,0,2)
if {(u in c(0:1))
fun=3*u*(1-u)^2
else (u in c(1:2))
fun=3*(2-u)*(1-u)^2}
if (y<fun)
{t=t+1
x[t]=u}}

You have a bunch of R syntax errors. You should review a basic R introduction. be careful with placement of braces. Also there is no in keyword in R.
n <- 10000
t <- 0
x <- 0
while(t<n) {
u <- runif(1,0,2)
y <- runif(1,0,2)
if (u > 0 & u < 1) {
fun <- 3*u*(1-u)^2
} else if (u >= 1 & u < 2) {
fun <- 3*(2-u)*(1-u)^2
} else {
fun <- 0
}
if (y<fun){
t <- t+1
x[t] <- u
}
}

Related

How to fix the problem with decimal numbers in a factorial function?

I am writing a code for the factorial function. My code is as follows:
f <- function(n) {
factorial <- 1
if( n < 0 )
print("Factorial of negative numbers is not possible")
else if( n == 0 )
print("Factorial of 0 is 1")
else {
for(i in 1:n)
factorial <- factorial * i
print(paste("Factorial of ",n," is ",factorial))
}
}
My problem with this code is for decimal numbers as input. For example for f(6.5) my code computes 720, but we know 6.5 ! does not exist. For decimal numbers like 6.5, 5/2, or sqrt(2) I would like to see a message like
"The factorial for this number does not exist".
How can I fix this problem in my code?
Something like this? This stops if n and as.integer(n) is not identical.
f <- function(n) {
if (as.integer(n) != n) {
stop("The factorial for this number does not exist")
}
factorial <- 1
if( n < 0 )
print("Factorial of negative numbers is not possible")
else if( n == 0 )
print("Factorial of 0 is 1")
else {
for(i in 1:n)
factorial <- factorial * i
print(paste("Factorial of ",n," is ",factorial))
}
}
f(5)
# [1] "Factorial of 5 is 120"
f(6.5)
# Error in f(6.5) : The factorial for this number does not exist
f(5/2)
# Error in f(5/2) : The factorial for this number does not exist
f(sqrt(2))
# Error in f(sqrt(2)) : The factorial for this number does not exist

Monte Carlo Method in R

I'm trying to learn R. I'm trying to write a program which calculates (approximately) pi.
Read About the method
My code is not working right now!
f <- 0
s <- 0
range <- 10000
for (i in (1:range)) {
v <- sample(1:range, 1)/range
n <- sample(1:range, 1)/range
if ( sqrt (v*v + n*n) <= 1) {
f <- f + 1
} else if ( v <=1 && n <= 1) {
s <- s+1
}
}
print ( f/s )
Here's an improved version of your code
range = 100000
v = runif(range)
n = runif(range)
f = sum(sqrt(v^2 + n^2) <= 1)
print(4 * f / range)
You should use runif to get samples from a uniform instead of sample(...) / range.
The s is unnecessary since what you're doing is counting the number of times, f, that your random point (v,n) is within the circle in that quadrant, divided by the number of attempted draws, which would just be range in your case.
You need to multiply by 4 since f / range approximates the area of one-quarter of the unit circle.

R lpsolve see all possible solutions of an integral LP

Is there a way to make lpSolve return multiple solutions? In below case i want (5,0) and (0,5) both.
If lpSolve cannot do that then is there any other R package which will return all possible solutions of an integral linear optimization program?
library("lpSolve")
A=matrix (c(1, 1), nrow=1, byrow=TRUE)
b=(5)
signs='=='
c_=c(1,1)
res = lpSolve::lp('max', c_, A, signs, b, all.int = TRUE)
res$solution
=======================================================================
I would also like to know why lpSolve package provides all possible solutions if all decision variables are binary. Why cannot it repeat the same when all variables are integer...
Code:
library(lpSolveAPI)
vBiv_of_v <- function (nbits,v){
taillev<-length(v)
taillevBivalent<-nbits*taillev
vBivalent<-rep(0,taillevBivalent)
for(iLg in seq(1,taillev)) {
iCoef<-1
for(iDelta in seq(1,nbits)){
vBivalent[(iLg-1)*nbits+iDelta]<- iCoef*v[iLg]
iCoef<-iCoef*2
}
}
vBivalent
}
vBiv_to_v <- function (nbits,vBivalent) {
taillevBivalent<-length(vBivalent)
taillev<-taillevBivalent/nbits
v<-rep(0,taillev)
for(iLg in seq(1,taillev)) {
for(iDelta in seq(1,nbits)){
v[iLg]<-v[iLg]+2^(iDelta-1)*vBivalent[(iLg-1)*nbits+iDelta]
}
}
v
}
nbVariable<-2
nbBits=3
nbVariableBivalentes<-nbVariable*nbBits
f.obj<-rep(0,nbVariableBivalentes)
mylp <- make.lp(0, nbVariableBivalentes)
set.objfn(mylp,f.obj)
add.constraint(mylp, vBiv_of_v(nbBits,c(1,1)), "=", 5)
set.type(mylp, 1:nbVariableBivalentes , type = "binary")
repeat {
status<-solve(mylp)
if(status == 0) {
last_sol<-get.variables(mylp)
vRes<-vBiv_to_v(nbBits,last_sol)
cat(vRes[1],vRes[2],"\n")
#add cutting
new_rhs <- 0;
f.condSup<-rep(0,nbVariableBivalentes)
for (iCol in 1:nbVariableBivalentes) {
f.condSup[iCol] <- 2 * last_sol[iCol] - 1
new_rhs <- new_rhs + last_sol[iCol];
}
add.constraint(mylp, f.condSup, "<=", new_rhs - 1)
}
else if(status == 2) {
cat("No more solution.\n")
break
}
}
Result:
5 0
4 1
3 2
1 4
2 3
0 5
No more solution.

R using "extract" Function: all cases discarded after aggregation

I'm trying to use the "extract" Function in R, which allows for Policy Mood analysis (documentation can be found here: http://www.unc.edu/~jstimson/Software_files/Doc.pdf). All of my cases are discarded, however, and I can't figure out whether the data or the function is the problem.
Here is a sample dataset with the code needed to execute the function (the "extract" function code is included further below):
library(car)
#create sample data frame
mat <- matrix(, nrow = 10, ncol = 0)
mat <- as.data.frame(mat)
mat$year <- c(1998,1999,2000,2001,2002,1996,1997,1998,2000,2002) #survey years
mat$varname <- c("ESS","ESS","ESS","ESS","ESS","ISSP","ISSP","ISSP","ISSP","ISSP") #survey names
mat$index <- c(10,20,30,20,30,10,20,30,20,10) #approval rating in survey
mat$ncases <- c(1000,1120,1300,800,1000,1200,1300,1400,1100,1000) #number of survey respondents
source("Extract.r") #loading Extract for estimating Mood
mat$date<-ISOdate(mat$year,1,1) #generate date variable
output<-extract(mat$varname,mat$date,mat$index,mat$ncases) #estimate mood series
The final line returns the following:
[1] "Series ESS discarded. After aggregation cases = 0"
[1] "Series ISSP discarded. After aggregation cases = 0"
Error in issue[, v] : subscript out of bounds
So the surveys are all being eliminated as unusable at aggregation. My best guess, looking at the function code below, is that the cases are being dropped for having uncomputable or zero standard deviations - but I don't understand why that would be the case.
Finally, here is the Extract.r code for the function. The code chunk I believe may be causing problems begins at "#NOW REDUCE ISSUE MATRIX TO ELIMINATE UNUSABLE SERIES (WN<2)":
display<-function(out,filename=NULL) {
if (is.null(filename)) filename=""
d<-out$dimensions
p<-out$period
m<-out$latent1
if (d==2) m2<-out$latent2
T<-out$T
mo=100*(p-as.integer(p))
for (t in 1:T) {
yr<-format(as.integer(p[t]),nsmall=0)
month<-format(mo[t],digits=2)
lat1<-format(m[t],nsmall=3)
if (d==1) {
cat(c(yr,month,lat1),fill=TRUE,file=filename,append=TRUE)
} else {
lat2<-format(m2[t],nsmall=3)
cat(c(yr,month,lat1,lat2),fill=TRUE,file=filename,append=TRUE)
}
}
}
##########################################################################################
plot.Zextract<-function(outobject) {
dim<- outobject$dimensions
T<- outobject$T
vect1<-outobject$latent1
t<-seq(1:T)
if (dim>1) {
vect2<-outobject$latent2
miny<-min(vect1)
if (miny>min(vect2)) miny<-min(vect2)
maxy<-max(vect1)
if (maxy<max(vect2)) maxy<-max(vect2)
dummy<-rep(miny,T-1) #dummy is a fake variable used to reset axes to handle min/max of both series
dummy[T]<-maxy
leg.text<-c("","Dimension 1","Dimension 2")
plot(t,dummy,type="l",lty=0,main="Final Estimation Results: Two Dimensions",xlab="Time Point",ylab="Latent Variables")
lines(t,vect1,col=1)
lines(t,vect2,col=2)
legend(1,maxy,leg.text,col=c(0,1,2),lty=c(0,1,1))
} else {
plot(t,vect1,type="l",main="Final Estimation Results",xlab="Time Point",ylab="Latent Variable")
if (dim == 2) lines(t,vect2,col=2)
}
}
##########################################################################################
summary.Zextract<- function(outobject) {
T=outobject$T
nvar=outobject$nvar
dim<- outobject$dimensions
vn<- c(outobject$varname,"Variable Name")
vn<- format(vn,justify="right")
nc<- format(outobject$N,justify="right")
ld<- format(outobject$loadings1,digits=3,justify="right")
mean<- format(outobject$means,digits=6,justify="right")
sd<- format(outobject$std.deviations,digits=6,justify="right")
cat("Variable Loadings and Descriptive Information: Dimension 1\n")
cat(paste(vn[nvar+1],"Cases","Loading"," Mean ","Std Dev","\n"))
for (v in 1:nvar) {
cat(paste(vn[v]," ",nc[v]," ",ld[v],mean[v],sd[v],"\n"))
}
if (dim == 2) {
ld<- format(outobject$loadings2,digits=3,justify="right")
cat("\nVariable Loadings and Descriptive Information: Dimension 2\n")
cat(paste(vn[nvar+1],"Cases","Loading"," Mean ","Std Dev","\n"))
for (v in 1:nvar) {
cat(paste(vn[v]," ",nc[v]," ",ld[v],mean[v],sd[v],"\n"))
}
}
}
##########################################################################################
findper<-function(unit,curdate,mind,miny,minper,aggratio) { #returns intFindPer
datcurdate<-curdate
class(datcurdate)<-"Date"
mo <- findmonth(datcurdate)
qu <- 1 + as.integer((mo - 1)/3)
dy <- findday(datcurdate)
yr <- findyear(datcurdate)
arinv<- 1/aggratio
if (unit == "D") intFindPer <- curdate - mind +1 #curdate - mindate + 1
if (unit == "A" || unit == "O") intFindPer <- as.integer((yr - miny) / aggratio) + 1
if (unit == "Q") part <- qu
if (unit == "M") part <- mo
if (unit == "Q" || unit == "M") intFindPer <- (yr - miny - 1) * arinv + part + (arinv - (minper - 1))
return(intFindPer)
} #findper
##########################################################################################
findday<-function(DateVar) {
z<-as.POSIXlt(DateVar)
v<-unlist(z)
findday<-as.integer(v[4])
} #end findday
##########################################################################################
findmonth<-function(DateVar) {
z<-as.POSIXlt(DateVar)
v<-unlist(z)
findmonth<-as.integer(v[5])+1
} #end findmonth
##########################################################################################
findyear<-function(DateVar) {
z<-as.POSIXlt(DateVar)
v<-unlist(z)
findyear<-as.integer(v[6])+1900
} #end findyear
##########################################################################################
aggregate<- function(varname,date,index,ncases,mindate,maxdate,nperiods,nvar,aggratio,unit,miny,minper) { #
#READ A NEW RECORD, CALCULATE PERIOD, AND SET UP AGGREGATION INTO MAT.ISSUE[NPERIODS,NVAR]
vl<- character(nvar)
mind<- as.integer(mindate)/86400
maxd<- as.integer(maxdate)/86400
vfac<- factor(varname) #make a factor vector
vlev<- levels(vfac) #find unique categories
Mat.Issue<- array(dim=c(nperiods,nvar))
nrec<-length(varname) #added for R compatibility
lp<- 0
per<- 0
x<- 0
c<- 0
nkeep<- 0
lv<- "0"
for (record in 1:nrec) { # MASTER LOOP THROUGH INPUT DATA, 1 TO NREC
if (ncases[record] == 0 || is.na(ncases[record])) ncases[record] <- 1000
mo <- findmonth(date[record])
qu <- 1 + as.integer((mo - 1)/3)
dy <- findday(date[record])
yr <- findyear(date[record])
curdate<- as.integer(date[record])
if (curdate >= mind && curdate <= maxd) { #is date within range?
nkeep <- nkeep + 1
if (nkeep==1) { #startup routine for first good case
firstcase<- TRUE
lp <- findper(unit,curdate,mind,miny,minper,aggratio)
lv <- varname[record]
x <- index[record] * ncases[record] #start new sums for case 1
c <- ncases[record]
for (i in 1:nvar) {
if (lv==vlev[i]) v=i #determine v by matching to position of labels vector
} #end for
} else {
firstcase<- FALSE
} #end if
if (firstcase == FALSE) { #skip over the rest for first good case
per<- findper(unit,curdate,mind,miny,minper,aggratio) #here we translate date into agg category
if ((varname[record] != lv) || (per !=lp)) { #found a new period or variable name
if (lp > 0 && lp <= nperiods) {
Mat.Issue[lp, v] <- x / c #recompute for either period or var change
x<- 0
c<- 0
}
if (varname[record] != lv) { #new var only
for (i in 1:nvar) {
if (varname[record]==vlev[i]) v=i #determine v by matching to position of labels vector
} #end for
vl[v]<- varname[record] #this will only catch names that have good cases
lv<-vl[v] #reassign new varname to lastvar
} # new var
lp <- findper(unit,curdate,mind,miny,minper,aggratio)
x <- index[record] * ncases[record] #start new sums for current case
c <- ncases[record]
} else {
x<- x + index[record] * ncases[record] #a continuing case, increment sums
c<- c + ncases[record]
}
} # end of first case special loop
} #end of date test loop
} #newrec: next record
vl<- vlev #overwrite previous assignment which had good names only
agglist<- list(lab=vl,iss=Mat.Issue)
return(agglist) #list includes labels and issue matrix
} #end aggregate function
##########################################################################################
esmooth<- function(mood, fb, alpha){
##########################################################################################
smooth<- function(alpha) { #for time series "series" and alpha "alpha[1]" compute sum of squared forecast error
ferror<- numeric(1)
T<- length(series)
xvect<- numeric(T)
xvect[1] <- series[1]
for (t in 2:T) {
xvect[t] <- alpha[1] * series[t] + (1 - alpha[1]) * xvect[t - 1]
}
sumsq <- 0
for (t in 3:T) {
ferror <- series[t] - xvect[t - 1]
sumsq <- sumsq + ferror ^ 2
}
return(sumsq) #this is the value of the function for a particular parameter alpha[1]
} # END OF FUNCTION SMOOTH
##########################################################################################
series<- mood[fb,] #create series to be smoothed
sm.out<- optim(c(.75),smooth,method="L-BFGS-B",lower=0.5,upper=1) #call smoother
alpha<- sm.out$par #assign result to alpha
#NOW SMOOTH USING ALPHA
T<- length(series)
for (t in 2:T) {
mood[fb,t] <- alpha * series[t] + (1 - alpha) * mood[fb,t - 1]
}
return(alpha)
} #END OF FUNCTION ESMOOTH
##########################################################################################
residmi<- function(issue,v,mood) { #function regresses issue(v) on mood and then residualizes it
o<- lm(issue[,v] ~ mood[3,]) #regress issue on mood to get a,b
issue[,v]<- 100 + issue[,v] - (o$coef[1]+o$coef[2]*mood[3,]) #100 + Y - (a+bx)
return(issue[,v])
}
##########################################################################################
iscorr<- function(issue,mood) { #compute issue-scale correlations
Nv<- length(issue[1,])
Np<- length(issue[,1])
Rvector<- numeric(Nv)
for (v in 1:Nv) {
N<- Np - sum(is.na(issue[,v]))
if (N > 1) Rvector[v]<- cor(issue[,v],mood[3,],use="complete.obs",method="pearson")
}
return(Rvector)
} #end function iscorr
##########################################################################################
dominate<- function(fb,issue,nperiods,nvar,mood,valid,smoothing,alpha) {
nitems<- numeric(nperiods)
if (fb==2) alpha1<-alpha
if (fb==1) {
unexp<-numeric(1)
everlap<- integer(1)
alpha<- 1
alpha1<- 1
}
if (fb == 1) {
startper <- 1
mood[fb, startper] <- 100
firstj <- 2
lastj <- nperiods
stepj <- 1
jprev <- 1
} else {
startper <- nperiods
mood[fb, startper] <- mood[1, nperiods] #reuse forward metric
firstj <- nperiods - 1
lastj <- 1
stepj <- -1
jprev <- nperiods
} # end if
for (j in seq(firstj,lastj,by=stepj)) {
mood[fb, j] <- 0
everlap <- 0 ## of years which have contributed sums to mood
if (fb == 1) {
firstj2 <- 1
lastj2 <- j - 1
} else {
firstj2 <- j + 1
lastj2 <- nperiods
} # end if
for (j2 in firstj2:lastj2) {
sum <- 0 #has already been estimated
consum <- 0 #sum of communalities across issues
overlap <- 0
for (v in 1:nvar) {
xj <- issue[j, v] #xj is base year value
sngx2 <- issue[j2, v] #sngx2 is comparison year value
if (!is.na(xj) && !is.na(sngx2)) {
overlap <- overlap + 1 #numb of issues contributing to sum
ratio <- xj / sngx2
if (csign[v] < 0) ratio <- 1 / ratio
sum <- sum + valid[v] * ratio * mood[fb, j2]
consum <- consum + valid[v]
} # end if
} #next v
if (overlap > 0) {
everlap <- everlap + 1
mood[fb, j] <- mood[fb, j] + sum / consum
} # end if
} #next j2
nitems[j] <- everlap
if (everlap > 0) mood[fb, j] <- mood[fb, j] / everlap else mood[fb, j] <- mood[fb, jprev] #if undefined, set to lag(mood)
jprev <- j #last value of j, whether lead or lag
} #next j
if (smoothing == TRUE) {
alpha<- esmooth(mood, fb, alpha) #NOW SMOOTH USING ALPHA
mood.sm<- mood[fb,] #set up alternate vector mood.sm
for (t in 2:nperiods) {
mood.sm[t]<- alpha*mood[fb,t]+(1-alpha)*mood.sm[t-1]
} #end for
mood[fb,]<- mood.sm #now assign back smoothed version
} else {
alpha1 <- 1
alpha <- 1
}
if (smoothing == TRUE && fb == 1) alpha1 <- alpha
dominate.out<- list(alpha1=alpha1,alpha=alpha,latent=mood[fb,]) #output object
return(dominate.out)
# return(mood[fb,])
} #end dominate algorithm
##########################################################################################
#begindt<-NA #ISOdate(2004,6,1)
#enddt<-NA #ISOdate(2004,10,31)
##########################################################################################
## MAIN EXTRACT CODE BEGINS HERE #########################################################
extract<- function(varname,date,index,ncases=NULL,unit="A",mult=1,begindt=NA,enddt=NA,npass=1,smoothing=TRUE,endmonth=12) {
formula<-match.call(extract)
nrecords<- length(varname)
if (is.null(ncases)) ncases<- rep(0,nrecords)
moddate<- date #create temporary date vector, leaving original unmodified
if ((unit=="A" || unit=="O") && endmonth<12) {
for (i in 1:nrecords) { #first loop through raw data file
month<- findmonth(moddate[i])
year<- findyear(moddate[i])
if (month>endmonth) moddate[i]<- ISOdate(year+1,1,1) #modified date become 1/1 of next year
} #end loop through data
} # end if
if (is.na(begindt)) minper<-findmonth(min(moddate)) else minper<-findmonth(begindt)
if (is.na(begindt)) miny<-findyear(min(moddate)) else miny<-findyear(begindt)
if (is.na(begindt)) minday<-findday(min(moddate)) else minday<-findday(begindt)
if (is.na(enddt)) maxper<-findmonth(max(moddate)) else maxper<-findmonth(enddt)
if (is.na(enddt)) maxy<-findyear(max(moddate)) else maxy<-findyear(enddt)
if (is.na(enddt)) maxday<-findday(max(moddate)) else maxday<-findday(enddt)
if (unit=="Q") {
minper<- as.integer((minper-1)/3)+1
maxper<- as.integer((maxper-1)/3)+1
}
mindate<- ISOdate(miny,minper,minday,0,0,0,tz="GMT")
maxdate<- ISOdate(maxy, maxper, maxday,0,0,0,tz="GMT") #86400=24*60*60
#SETCONS:
latent<- numeric(1)
aggratio<- 0
fb<- 1 #initialize
auto<- "start" #meaningless value
alpha<- 1
alpha1<- 1
pass<- 1
holdtola<- 0.001
tola<- holdtola
iter<- 0
lastconv<- 99999
wtmean<- 0 #for it=1
wtstd<- 1
fract<- 1
if (unit=="A") {
nperiods<- maxy-miny+1
aggratio<- 1
months<- 12
}
if (unit=="O") {
years<- mult
months<- years*12
aggratio<- 2
odd<- (maxy-miny+1) %% mult #mod
nperiods=as.integer((maxy-miny)/mult) + odd
}
if (unit=="M") {
fract<- 100
nperiods<- (maxy-miny)*12
nperiods<- nperiods-12 + (12-minper+1) + maxper
aggratio<- 1/12
months<- 1
}
if (unit=="Q") {
aggratio<- 1/4
months<- 3
nperiods<- as.integer((maxy-miny)/aggratio)
nperiods<- nperiods-4 + (4-minper+1) + maxper
fract<- 10
}
if (unit=="D") {
months=1
nperiods<- (as.integer(maxdate)-as.integer(mindate))/86400 + 1 #86400=24*60*60
}
arinv<- 1/aggratio
aggratio<- months/12
nrecords<- length(index)
#HERE WE SET UP FUNDAMENTAL DIMENSIONS AND DECLARE VECTORS
if (fb != 2) mood<- array(dim=c(3,nperiods))
vfac<- factor(varname) #make a factor vector
vlev<- levels(vfac) #find unique categories
nvar<- length(vlev) #how many are there?, includes unusable series
valid<- numeric(nvar)
csign<<- numeric(nvar)
vl<- character(nvar)
r<- numeric(nvar)
oldr<- rep(1,nvar) # r=1 for all v initially
issue<- array(dim=c(nperiods,nvar))
count<- numeric(nperiods)
vl<- numeric(nvar)
period<- numeric(nperiods)
converge<- 0
evalue<- 0
# create numeric variable period, eg, yyyy.0m
if (unit=="D") {
period<-seq(1:nperiods)
} else {
if (months >= 12) {
for (l in 1:nperiods) {
p <- (l - 1) * aggratio
period[l] <- miny + p
} #next l
} else {
y <- 0
i <- 0
my <- miny
if (minper == 1) my <- my - 1
for (l in 1:nperiods) {
i<- 1 + ((l-1) %% arinv)
mq <- minper + i - 1
mq<- 1 + ((mq-1) %% arinv)
if (mq == 1) y <- y + 1 #first month or quarter, increment year
period[l] <- my + y + mq / fract
} # end for
} #end else
} # end if
agglist<- aggregate(varname,moddate,index,ncases,mindate,maxdate,nperiods,nvar,aggratio,unit,miny,minper) # call aggregate to produce issue matrix
vl<- agglist$lab #extract two elements of the list from aggregate call
issue<- agglist$iss
rm(agglist) #don't need this anymore
#NOW REDUCE ISSUE MATRIX TO ELIMINATE UNUSABLE SERIES (WN<2)
ndrop<- 0
nissue<- numeric(nperiods)
std<- numeric(nperiods)
for (v in 1:nvar) {
std[v]<- 0 #default
nissue[v]<- sum(!is.na(issue[,v])) #criterion is 2 cases for npass=1 or 3 for npass=2
if (nissue[v]>npass) std[v]<- sqrt(var(issue[,v],na.rm=TRUE)) #this is just a test for variance >0
if (std[v]<.001) { #case dropped if std uncomputable (NA) or actually zero (constant)
ndrop<- ndrop+1
print(paste("Series",vl[v],"discarded. After aggregation cases =",nissue[v]))
}
}
nvarold<- nvar
nvar<- nvar-ndrop
pointer<- 1
found<- FALSE
for (v in 1:nvar) { #now reduced nvar
while (found==FALSE && pointer<=nvarold) { #find first valid column and push down
if (std[pointer]>.001) { #good case, transfer
issue[,v]<- issue[,pointer]
vl[v]<- vl[pointer]
pointer<- pointer+1
found<- TRUE
} else {
pointer<- pointer+1 #bad case, increment pointer
} #end if
} #end while
found<- FALSE
} #for
length(vl)<- nvar #reduce
length(issue)<- nperiods*nvar #chop off unused columns
attr(issue,"dim")<- c(nperiods,nvar)
N<- numeric(nvar)
#export<<-list(nperiods,nvar,issue)
for (pass in 1:npass) { #newpass: RESTART FOR SECOND DIMENSION CASE
if (pass == 2) { #reset iteration control parameters
iter <- 0
tola = holdtola
lastconv <- 99999
converge<- lastconv
conv<- converge
} else {
av<- numeric(nvar)
std<- numeric(nvar)
# ngood<- 0
for (v in 1:nvar) { #compute av and std by issue nvar now reduced to good cases
wn<- as.integer(nperiods-sum(is.na(issue[,v])))
av[v] <- mean(issue[,v],na.rm=TRUE)
std[v]<- sqrt(var(issue[,v],na.rm=TRUE) * ((wn - 1)/wn)) #convert to population standard deviation
issue[,v]<- 100 + 10 * (issue[,v] - av[v])/std[v] #standardize
# ngood<- ngood+1
}#end for
}
#READY FOR ESTIMATION, SET UP AND PRINT OPTIONS INFO
out<- as.character(10) #initial length only
out[1]<- print(paste("Estimation report:"))
if (pass == 1) {
if (months >= 12) {
out[2]<- print(paste("Period:", miny, " to", maxy," ", nperiods, " time points"))
} else {
out[2]<- print(paste("Period:", miny, minper, " to", maxy, maxper, nperiods, " time points"))
}
out[3]<- print(paste("Number of series: ", nvar+ndrop))
out[4]<- print(paste("Number of usable series: ", nvar))
out[5]<- print(paste("Exponential smoothing: ",smoothing))
}
out[6]<- print(paste("Iteration history: Dimension ",pass))
print(" ")
out[7]<- print("Iter Convergence Criterion Reliability Alphaf Alphab")
outcount<- 7
for (p in 1:nperiods) {
count[p]<- sum(!is.na(issue[p,]))
}
valid<- rep(1,times=nvar)
csign<<- rep(1,times=nvar)
auto <- "y" #iterative estimation on by default
quit <- 0 #false implies go ahead and estimate
while (iter == 0 || converge > tola) { #MASTER CONTROL LOOP WHICH ITERATES UNTIL SOLUTION REACHED
for (fb in 1:2) { # MASTER fb LOOP fb=1 is forward, 2 backward
dominate.out<- dominate(fb,issue,nperiods,nvar,mood,valid,smoothing,alpha) #master estimation routine
alpha1<- dominate.out$alpha1
alpha<- dominate.out$alpha
mood[fb,]<- dominate.out$latent
} #next fb
fb <- 3 #average mood from here on
for (p in 1:nperiods) { # AVERAGE
mood[fb, p] <- (mood[1, p] + mood[2, p]) / 2
} #next p
moodmean<-mean(mood[3,])
sdmood<-sd(mood[3,])
for (p in 1:nperiods) { #PLACEMENT OF THIS LOOP MAY NOT BE RIGHT
mood[fb,p] <- ((mood[fb,p] - moodmean) * wtstd / sdmood) + wtmean
} #end for
#plot commands
t<- seq(1:nperiods) #time counter used for plot below
lo<- 50 #force scale of iterative plot to large range
hi<- 150
if (min(mood[3,]) < lo) lo=min(mood[3,]) #whichever larger, use
if (max(mood[3,]) > hi) hi=max(mood[3,])
dummy<- rep(lo,nperiods) #dummy is fake variable used to set plot y axis to 50,150
dummy[nperiods]<- hi
if (iter==0) {
plot(t,dummy,type="l",lty=0,xlab="Time Period",ylab="Estimate by iteration",main="Estimated Latent Dimension") #create box, no visible lines
} else {
lines(t,mood[3,],col=iter)
}
iter <- iter + 1
if (auto == "y") r<- iscorr(issue,mood) else auto <- "y" #recompute correlations
wtmean<- 0
wtstd<- 0
vsum<- 0
goodvar<- 0
converge<- 0 #start off default
evalue<- 0
totalvar<- 0
for (v in 1:nvar) {
wn<- nperiods-sum(is.na(issue[,v]))
if (!is.na(sign(r[v]))) csign[v]<<- sign(r[v])
wn<- nperiods-sum(is.na(issue[,v]))
if (wn>1) { #sum over variables actually used
vratio <- wn / nperiods
evalue <- evalue + vratio * r[v]^2
totalvar <- totalvar + vratio
} #end if
#convergence tests
if (wn > 3) {
conv <- abs(r[v] - oldr[v]) #conv is convergence test for item=v
conv <- conv * (wn / nperiods) #weight criterion by number of available periods
if (conv > converge) converge <- conv #converge is the global max of conv
} #end if
if (!is.na(r[v])) oldr[v] <- r[v]
if (!is.na(r[v])) valid[v] <- r[v]^2
if (!is.na(av[v])) wtmean <- wtmean + av[v] * valid[v]
if (!is.na(std[v])) wtstd <- wtstd + std[v] * valid[v]
if (!is.na(r[v])) vsum <- vsum + valid[v]
} #end v loop
if (vsum > 0) wtmean <- wtmean / vsum
if (vsum > 0) wtstd <- wtstd / vsum
if (pass == 1) {
mean1 <- wtmean
std1 <- wtstd
e1=evalue
} else {
wtmean <- mean1
wtstd <- std1 #*unexp
} #end if
fbcorr <- cor(mood[1,],mood[2,]) #fnfrontback
if (quit != 1) {
outcount<- outcount+1
cv<- format(round(converge,4),nsmall=4)
itfmt<-format(round(iter),justify="right",length=4)
out[outcount]<- print(paste(itfmt," ",cv," ",round(tola,4)," ",round(fbcorr,3),round(alpha1,4),round(alpha,4)))
}
if (converge > lastconv) tola <- tola * 2
lastconv <- converge
auto = "y" #skip corr on iter=1, set auto on
if (iter >= 50) break #get out of while loop
} #END MASTER WHILE ITERATION CONTROL LOOP
if (auto == "y" && converge<tola) { #IF WE REACH THIS CODE WE HAVE A FINAL SOLUTION TO BE REPORTED
if (pass == 1) out1<- out #hold output for 2 dimensional solution
auto <- "Q"
quit <- 1 #flag solution reached, last time through
r<- iscorr(issue,mood) #final iteration correlations
if (pass == 1) r1<- r #hold correlations for 2 dimensional solution
if (pass > 1) {
unexp <- totalvar
totalvar <- unexp * totalvar
evalue <- evalue * unexp
} # end if
if (pass == 1) {
expprop <- evalue / totalvar
tot1 <- totalvar
} else {
erel <- evalue / totalvar #% exp relative
totalvar <- (1 - expprop) * tot1 #true var=original var discounted by %exp
evalue <- erel * totalvar #rescale to retain %exp relationship
expprop <- evalue / tot1 #now reduce eral to expprop
} # end if
for (v in 1:nvar) {
N[v]<- sum(!is.na(issue[,v]))
}
var.out<- list(varname=vl,loadings=r,means=av,std.deviations=std)
print(" ")
outcount<- outcount+1
out[outcount]<- print(paste("Eigen Estimate ", round(evalue,2), " of possible ",round(tot1,2)))
outcount<- outcount+1
out[outcount]<- print(paste(" Percent Variance Explained: ",round(100 * expprop,2)))
if (pass != 2 && npass>1) {
for (v in 1:nvar) {
valid[v] <- 0 #reset all, regmoodissue will set good=1
if (csign[v] != 0) issue[,v]<- residmi(issue,v,mood) #regmoodissue()
} #v loop
} # if
#begin prn output routine # mood[fb,] is now our estimate, WHAT ABOUT A SECOND DIMENSION
latent<- mood[fb,] #vector holds values for output
if (pass == 1) latent1<- latent #hold first dimension
print(" ")
out[outcount+1]<- print(paste("Final Weighted Average Metric: Mean: ",round(wtmean,2)," St. Dev: ",round(wtstd,2)))
#for Zelig output
if (npass==1) {
extract.out<- list(formula=formula,T=nperiods,nvar=nvar,unit=unit,dimensions=npass,period=period,varname=vl,N=N,means=av,std.deviations=std,setup1=out1,loadings1=r1,latent1=latent1)
} else {
for (i in 6:outcount) {
out[i-5]=out[i]
}
length(out)<- outcount-5
extract.out<- list(formula=formula,T=nperiods,nvar=nvar,unit=unit,dimensions=npass,period=period,varname=vl,N=N,means=av,std.deviations=std,setup1=out1,loadings1=r1,latent1=latent1,setup2=out,loadings2=r,latent2=latent)
}
} #end if auto="y"
} #end of for pass=1,2 loop
par(col=1) #reset on termination
class(extract.out)<- "Zextract"
return(extract.out)
} #end of extract
Anyone have any ideas what's going wrong here? Thanks in advance for your time!
The issue here seems to be dates inside the aggregate function (note, not the base R aggregate). Namely, a minimum and maximum date are calculated as:
mind<- as.integer(mindate)/86400
maxd<- as.integer(maxdate)/86400
These are then compared (inside a loop for each date) against the curdate variable, using an if statement:
if (curdate >= mind && curdate <= maxd) { #is date within range?
The problem, though, is that curdate<- as.integer(date[record]) (the line immediately before the if statement) is not on the same time scale. Changing it to: curdate<- as.integer(date[record])/86400 seems to solve the problem.

Characteristic function for algebraic (linear?) function

I would like to create matrix A[i,j,k] with the following elements:
A[i,j,k] = 0 if k+j-s-i =/= 0
A[i,j,k] = p[s] if k+j-s-i =0 ( p[s] is given vector )
This may be written by characteristic function as p[s]*ð(k+j-s-i) or by Kronecker delta function as p[s]*ð(0,k+j-s-i).
Is there any "build in" function in R which gives that - I mean is there "ð" built in?
Or do I have to wrote it by myself?
I suppose it would be very useful to have built function which returns 1 for f(x)=0 and 0 otherwise, at least for linear f(x)
I'd rewrite this as
A[i,j,k] = p[k+j-i] if that exists, otherwise 0
which could then be implemented as
p <- c(1,2,3,4,5)
pfun <- function(x) {
if (x < 1 | x > length(p)) {
0
} else {
p[x]
}
}
n <- 5
A <- array(0, c(n, n, n))
for (i in 1:n) {
for (j in 1:n) {
for (k in 1:n) {
A[i,j,k] <- pfun(k+j-i)
}
}
}
There may be something more elegant than triply-nested for loops.
As for a the function you ask about, something as simple as
as.numeric(f(x)==0)
would work.

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