Applying a loess smoothing to a time series
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I would like to smooth a time curve, that I have plotted, by applying a loess function, but I can't get it to work.
An example:

    mydat <- runif(50)
    day1 <- as.POSIXct("2012-07-13", tz = "UTC")
    day2 <- day1 + 49*3600*24
    pdays <- seq(day1, day2, by = "days")
    lo <- loess(mydat ~ pdays)
I get the following message:

    Error: NA/NaN/Inf in foreign function call (arg 2)
Is it possible to apply a loess smoothing to a time series

Any help or guidance is greatly appreciated!