test the distance between two strata within a species.

harvesine.dist.R

ha <- function(x){
    x$Lat<-(as.numeric(paste(x$Lat)))
    x$Lon<-(as.numeric(paste(x$Lon)))
    pre<-x[(x[,17]==0),]
    post<-x[(x[,17]==1),]
    if(nrow(pre)<2| nrow(post)<2){results<-paste("not enought records per phase")}else{
    early <- x[(which.min(x$Year)),]
    e1 <- early[1,]
    predist<-apply(pre, 1, function(x) distHaversine(as.numeric(e1[4:3]),as.numeric(x[4:3]), r=6378137))
    postdist<-apply(post, 1, function(x) distHaversine(as.numeric(e1[4:3]),as.numeric(x[4:3]), r=6378137))
    mean.predist<-mean(predist)
    mean.postdist<-mean(postdist)
    ttest<-t.test(predist, postdist)
    sig <- ifelse(ttest$p.value <= 0.05, c(1), c(0))
    ks.test<-ks.test(predist, postdist)
    ks.sig<-ifelse(ks.test$p.value <= 0.05, c(1), c(0))
    results<-t(c(paste(unique(x$Species)),mean.predist,mean.postdist,ttest$p.value,sig,ks.sig ))
    #colnames(results)<-c("Species", "mean.lag.dist", "mean.postlag.dist", "p.value", "sig", "ks.test.sig")
    return(results)}
    }