title: How to display date format (Sep-12) in bar chart and set y axis limit?
body: <p>I have two questions on building a bar plot by using ggplot().</p>
  
  <h2>How to display data format (Sep-12)?</h2>
  
  <p>I would like to display the date in the format of Sep-12. My data is a quarterly summary. I would like to show Mar, Jun, Sep and Dec quarters. However, I used the as.Date(YearQuarter) within the ggplot() function. It shows a different sequence of Apr, July, Oct, Jan.</p>
  
  <h2>How to increase y axis limit?</h2>
  
  <p>The y axis is set at 70%, one of value label is out of the picutre. I have added ylim(0,1) to increase the y limit to 1. However, I lost the percentage format as the y axis is not displaying the percentage anymore.</p>
  
  <pre><code>x4.can.t.m &lt;- structure(list(NR_CAT = structure(c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 
  2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 
  3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L, 
  1L, 2L, 3L, 1L, 2L, 3L), .Label = c("0%", "1 to 84%", "85% +"
  ), class = "factor"), TYPE = structure(c(1L, 1L, 1L, 2L, 2L, 
  2L, 3L, 3L, 3L, 1L, 1L, 1L, 2L, 2L, 2L, 3L, 3L, 3L, 1L, 1L, 1L, 
  2L, 2L, 2L, 3L, 3L, 3L, 1L, 1L, 1L, 2L, 2L, 2L, 3L, 3L, 3L, 1L, 
  1L, 1L, 2L, 2L, 2L, 3L, 3L, 3L), .Label = c("PM BUSINESS", "PM CONSUMER", 
  "PREPAY"), class = "factor"), YearQuarter = structure(c(1L, 1L, 
  1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
  3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 
  4L, 4L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L), .Label = c("2011-09-01", 
  "2011-12-01", "2012-03-01", "2012-06-01", "2012-09-01"), class = "factor"), 
      value = c(0.5, 0, 0.5, 0.35, 0, 0.65, 0.28, 0.02, 0.7, 0.4, 
      0, 0.6, 0.38, 0, 0.62, 0.43, 0.01, 0.56, 0.57, 0, 0.43, 0.35, 
      0, 0.65, 0.39, 0.01, 0.6, 0.55, 0, 0.45, 0.4, 0.02, 0.58, 
      0.35, 0.02, 0.63, 0.35, 0, 0.65, 0.55, 0.01, 0.44, 0.47, 
      0, 0.53)), .Names = c("NR_CAT", "TYPE", "YearQuarter", "value"
  ), row.names = c(NA, -45L), class = "data.frame")
  </code></pre>
  
  <p>This is my plot code:</p>
  
  <pre><code>x4.can.t.m$YearQuarter &lt;- as.Date(x4.can.t.m$YearQuarter)
  x4.can.t.d.bar &lt;- ggplot(data=x4.can.t.m, aes(x=YearQuarter, y=value,fill=NR_CAT)) + 
                    geom_bar(stat="identity",position = "dodge",ymax=NR_CAT+0.2) +
                facet_wrap(~TYPE,ncol=1) +
                    geom_text(aes(label =paste(round(value*100,0),"%",sep="")), 
                               position=position_dodge(width=0.9), 
                               vjust=-0.25,size=3)  +
          scale_y_continuous(formatter='percent',ylim=1) +
              labs(y="Percentage",x="Year Quarter") +
              ylim(0,100%)
  
  
  x4.can.t.d.bar +scale_fill_manual("Canopy Indicators",values=tourism.cols(c(6,9,8)))+
                  opts(title="Canopy Indicator: All Customers portout for Network 
                              Issues",size=4)
  </code></pre>