figure caption in r markdown
---
title: "Plotting"
author: "xx"
date: '2015-08-10'
output: pdf_document
---
```{r figs, echo=FALSE, fig.width=7,fig.height=6,fig.cap="plotting example"}
par(mfrow=c(2,2))
plot(1:10, col=2)
plot(density(runif(100, 0.0, 1.0)))
plot(runif(100, 0.0, 1.0),type="l")
```
in Figure \ref{fig:figs} we see examples of plotting in R.