What is the difference between executing and sourcing scripts in R
r
Solution
This seems likely to be related to The R-FAQ in section 7 relating to why grid based graphics do not get plotted. Try using explicit `print` or `plot` command.
Reading the first sentence of "Details" in the help page for `source` to you:
`Details
Note that running code via source differs in a few respects from entering it at the R command line. Since expressions are not executed at the top level, auto-printing is not done.` (And I'm glad to see that you did read the rest of that section.)
Problem
A basic question as I am starting out R. What is the main difference when I am sourcing a R script vs executing it? I am trying to get ggplot2 example scripts running. ``` library("ggplot2") d = data.frame(x1=c(1,3,1,5,4), x2=c(2,4,3,6,6), y1=c(1,1,4,1,3), y2=c(2,2,5,3,5), t=c('a','a','a','b','b'), r=c(1,2,3,4,5)) ggplot() + scale_x_continuous(name="x") + scale_y_continuous(name="y") + geom_rect(data=d, mapping=aes(xmin=x1, xmax=x2, ymin=y1, ymax=y2, fill=t),color="black",alpha=0.5) + geom_text(data=d, aes(x1+(x2-x1)/2,y=y1+(y2-y1)/2, label=r), size=4) + opts(title="geom_rect", plot.title=theme_text(size=40, vjust=1.5)) ``` When I source this script, no plots appear. I understand this has to do with lack of explicit print statement in my code. I've read a discussion that when you execute a command in the interactive shell, the print statement is implicit. My question is this - When I execute a script vs source it, what is the basic difference? When would I do one over another? Thanks!