title: How to make a barplot with data where one of the columns already contains the frequencies/counts
body: <p>I'm trying to plot the number of samples that have data for for each of several traits. I actually already have a column of data containing these numbers of samples, and was simply hoping to plot it as the "frequency". As it is, I'm not quite sure where the frequency data is coming from (see code below). Please let me know whether I can clarify anything. Many thanks!:</p>
  
  <pre><code>##my data
  data&lt;-structure(list(V1 = structure(c(2L, 1L), .Label = c("593", "QnWeight_initial"
  ), class = "factor"), V2 = structure(c(2L, 1L), .Label = c("566", 
  "Head"), class = "factor"), V3 = structure(c(2L, 1L), .Label = c("535", 
  "V1"), class = "factor"), V4 = structure(c(2L, 1L), .Label = c("535", 
  "V2"), class = "factor"), V5 = structure(c(2L, 1L), .Label = c("535", 
  "V3"), class = "factor"), V6 = structure(c(2L, 1L), .Label = c("482", 
  "Left_Leg"), class = "factor"), V7 = structure(c(2L, 1L), .Label = c("474", 
  "Left_Antenna"), class = "factor"), V8 = structure(c(2L, 1L), .Label = c("237", 
  "Qn_Weight_Loss"), class = "factor"), V9 = structure(c(2L, 1L
  ), .Label = c("230", "Days_wrkr_eclosion"), class = "factor"), 
      V10 = structure(c(2L, 1L), .Label = c("81", "Growth_all"), class = "factor"), 
      V11 = structure(c(2L, 1L), .Label = c("79", "Growth_1_2"), class = "factor"), 
      V12 = structure(c(2L, 1L), .Label = c("62", "Growth_1_3"), class = "factor"), 
      V13 = structure(c(2L, 1L), .Label = c("60", "Growth_2_3"), class = "factor"), 
      V14 = structure(c(2L, 1L), .Label = c("51", "Right_Antenna"
      ), class = "factor"), V15 = structure(c(2L, 1L), .Label = c("49", 
      "Left_Leg_Remeasure"), class = "factor"), V16 = structure(c(2L, 
      1L), .Label = c("49", "Right_Leg"), class = "factor"), V17 = structure(c(2L, 
      1L), .Label = c("47", "Head_Remeasure"), class = "factor"), 
      V18 = structure(c(2L, 1L), .Label = c("46", "Left_Antenna_Remeasure"
      ), class = "factor")), .Names = c("V1", "V2", "V3", "V4", 
  "V5", "V6", "V7", "V8", "V9", "V10", "V11", "V12", "V13", "V14", 
  "V15", "V16", "V17", "V18"), class = "data.frame", row.names = c(NA, 
  -2L))
  dat&lt;-data.frame(fac=unlist(data[1,, drop=FALSE]), freqs=unlist(data[2,, drop=FALSE]))
  t&lt;-table(rep(as.character(dat[, 1]), dat[, 2]))
  
  ##the plot I'm making at the moment
  barplot(t, main="Sample Sizes of Various Fitness Traits", xaxt='n', xlab='', width=0.85)
  labels&lt;-unlist(data[1,,drop=FALSE])
  text(1:18, par("usr")[3] -0.25, srt=90, adj=1,labels=labels,xpd=TRUE, cex=0.6)
  
  
  ##The kind of plot I'm looking to make
  par(las=2) # make label text perpendicular to axis
  par(mar=c(5,8,4,2)) # increase y-axis margin.
  
  print(mtcars$gear)
  counts &lt;- table(mtcars$gear)
  print(counts)
  barplot(counts, main="Car Distribution", names.arg=c("3 Gears", "4 Gears", "5   Gears"), cex.names=0.8)
  </code></pre>