You can use basic debugging techniques to help understand what is going
wrong. For example, insert a cat() statement right before the statement
which is giving the warning. Like this:
## your code
mses[st]<-sum(resid(model)^2)/(length(xi)-2)
ssr<-var(yi)*(length(xi)-1)-sum(resid(model)^2)
## insert two lines
tmp <- (var(yi)*(length(xi)-1))
cat('i',i,'st',st,'ssr',ssr,'denominator',tmp,'\n')
## continue with your code
rsquares[st]<-ssr/(var(yi)*(length(xi)-1))
fRatio<-ssr/mses[st]
This example should help you understand the warning message
> foo <- numeric(5)
> foo[2] <- c(1,3)
Warning message:
In foo[2] <- c(1, 3) :
number of items to replace is not a multiple of replacement length
--
Don MacQueen
Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062
On 5/16/13 3:17 AM, "rishard" <or...@uclive.ac.nz> wrote:
>Hey I'm not really sure what I should put on here, but I am having trouble
>with my R code. I am trying to get the p-values, R^2s etc for a number of
>different groups of variables that are all in one dataset.
>
>This is the code:
>
>#Stand counter
>st<-1
>#Collections
>stands<-numeric(67)
>slopes<-numeric(67)
>intercepts<-numeric(67)
>mses<-numeric(67)
>rsquares<-numeric(67)
>pValues<-numeric(67)
>#Start lists for X and Y values within each stand
>xi<-numeric(0)
>yi<-numeric(0)
>#Set the first element to the starting X and Y values
>xi[1]=X[1]
>yi[1]=Y[1]
>#Start looping working through your data, record by record
>for (i in 2:length(X)) {
> #If you are in the same stand as on the last record, continue to
> #collect X and Y values
> if(Stand[i]==Stand[i-1]) {
> xi=cbind(xi,X[i])
> yi=cbind(yi,Y[i])
> } else {
> #If a new stand is encountered make your linear model and
> #collect statistics
> model<-lm(yi~xi)
> stands[st]<-Stand[i-1]
> intercepts[st]<-model$coefficients[1]
> slopes[st]<-model$coefficients[2]
> mses[st]<-sum(resid(model)^2)/(length(xi)-2)
> ssr<-var(yi)*(length(xi)-1)-sum(resid(model)^2)
> rsquares[st]<-ssr/(var(yi)*(length(xi)-1))
> fRatio<-ssr/mses[st]
> pValues[st]<-1-pf(fRatio,1,length(xi)-2)
> #Increment the stand number, zero the within stand collections,
> #and start again
> st<-st+1
> xi<-numeric(0)
> yi<-numeric(0)
> xi[1]=X[i]
> yi[1]=Y[i]
> }
>}
>#Make your data set
>standEstimates<-data.frame(standID=stands,intercept=intercepts,slop=slopes
>,mse=mses,rSquare=rsquares,pValue=pValues)
>
>The standEstimate outputs look like this:
>
>standID intercept slop mse rSquare pValue
>1 6833 319.2470 NA 0 NA NA
>2 756 708.7470 NA 0 NA NA
>3 795 508.2290 NA 0 NA NA
>4 1249 503.1460 NA 0 NA NA
>5 1331 703.0620 NA 0 NA NA
>6 1417 747.7620 NA 0 NA NA
>7 4715 549.3400 NA 0 NA NA
>8 4850 603.9940 NA 0 NA NA
>9 2105 573.3270 NA 0 NA NA
>Etc etc
>
>and I get these warnings:
>
>1: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>2: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>3: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>4: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>5: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>6: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>7: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>8: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>9: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>10: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>11: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>12: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
> number of items to replace is not a multiple of replacement length
>13: In rsquares[st] <- ssr/(var(yi) * (length(xi) - 1)) :
> number of items to replace is not a multiple of replacement length
>14: In pValues[st] <- 1 - pf(fRatio, 1, length(xi) - 2) :
>etc etc
>
>Sorry if I haven't set this post out right, or haven't provided enough
>information. But can anyone see why it is not giving me any returns for
>R^2
>etc?
>
>
>
>--
>View this message in context:
>http://r.789695.n4.nabble.com/R-looping-help-tp4667180.html
>Sent from the R help mailing list archive at Nabble.com.
>
>______________________________________________
>R-help@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.
______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
