code error in calcBetweenGroupsVariance funciton code.

[Dr-A-Soni]

The below code seems to be not working for me even when I copy and paste it without anychange.

calcBetweenGroupsVariance <- function(variable,groupvariable)
{
# find out how many values the group variable can take
groupvariable2 <- as.factor(groupvariable[[1]])
levels <- levels(groupvariable2)
numlevels <- length(levels)
# calculate the overall grand mean:
grandmean <- mean(variable)
# get the mean and standard deviation for each group:
numtotal <- 0
denomtotal <- 0
for (i in 1:numlevels)
{
leveli <- levels[i]
levelidata <- variable[groupvariable==leveli,]
levelilength <- length(levelidata)
# get the mean and standard deviation for group i:
meani <- mean(levelidata)
sdi <- sd(levelidata)
numi <- levelilength * ((meani - grandmean)^2)
denomi <- levelilength
numtotal <- numtotal + numi
denomtotal <- denomtotal + denomi
}
# calculate the between-groups variance
Vb <- numtotal / (numlevels - 1)
Vb <- Vb[[1]]
return(Vb)
}

I get NA while running this code.

[Dr-A-Soni]

(#3 (comment))
tried this comment and it worked. @BenjaminKay thanx. #3