[R] ggplot does not show in knitr

[Michael Weylandt]

You need to explicitly print() the graphs to make them show -- or in recent ggplot2 versions I think you can also use plot() as an alias. 

Michael

On Aug 2, 2012, at 2:37 PM, "firdaus.janoos" <fjanoos at bwh.harvard.edu> wrote:

> Hello,
> 
> I'm having some issues getting a ggplot figure to show up in the knitr
> output, when placed in a loop.
> 
> Specifically, I have a loop inside a knitr chunk :
> 
> ```{r fitting, warning=FALSE, fig.width=10, fig.height=10, fig.keep='high'}
> for (t in 1:T)
> {
>      # do a regression of tgt.vals ~ predictors and compute coeffs and
> fitted values (fit.vals / fit.adj.vals)
> 
>    plot( x=tgt.vals, y=fit.vals );
>    plot( x=tgt.vals, y = fit.adj.vals );
> 
>    qplot( x = pred.names, y = coeffs);
> 
> }
> 
> ```
> 
> The html output file shows the output of first 2 plot commands but not that
> of the qplot command. Even if i remove the 2 plots and keep only the qplot
> in the loop, it does not display in the html output.
> The qplot just by itself, not in a loop, displays fine. Also, there are no
> issues when I run in regular R.
> 
> Any suggestions of what is going on ?
> 
>    [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.