How to apply a code for multiple columns?

Question

[gtoerienhowie]

Hi. I am new to R and have the following example code that I wish to apply for every column in my data.

data(economics, package="ggplot2")
economics$index <- 1:nrow(economics)
loessMod10 <- loess(uempmed ~ index, data=economics, span=0.10)
smoothed10 <- predict(loessMod10)
plot(economics$uempmed, x=economics$date, type="l", main="Loess Smoothing and Prediction", xlab="Date", ylab="Unemployment (Median)")
lines(smoothed10, x=economics$date, col="red")

Could someone please suggest how this would be possible?

Thanks!

[cpad0112]

read about apply

[gtoerienhowie]

Thank you, but I am stuck at writing an apply function at saving the output from loess and plot. Could you please help me with that?

Answer 1

[JJDollar]

What function do you want to apply to each column exactly? To apply a function to each column, you can use something like this.

apply(m, 2, function(x) max(x))

Where m = matrix/data.frame 2 = means to apply the function column wise (use 1 to apply function row-wise). And the function you want to apply is the third input. In the example, this code would just give the max value for each column.

This link maybe helpful! https://www.r-bloggers.com/2012/12/using-apply-sapply-lapply-in-r/

[gtoerienhowie]

Thank you, but I am stuck at writing the function at saving the output from loess and plot. Could you please help me with that?