title: Assigning shapes to variables in a correlation circle plot
body: <p>I would like to know if it is possible to set different shapes to the column names in the plot instead of the labels. I have shown a reproducible example to obtain the plot.</p>
  
  <pre><code>#dataset
  mtcars
  
  #split the data into different blocks
  a&lt;-mtcars[,1:3]
  b&lt;-mtcars[,4:6]
  c&lt;-mtcars[,7:9]
  d&lt;-mtcars[,10:11]
  
  ### create a list of dataframes
  A&lt;-list(blockA=a, blockB=b,blockC=c,blockD=d)
  
  ### design matrix
  C &lt;- matrix(c(0, 0, 0, 0,  
                0, 0, 0, 0, 
                0, 0, 0, 0, 
                1, 1, 1, 1), 4, 4)
  tau = c(1, 1, 1, 1)
  library(mixOmics)
  
  ##### computing the sGCCA
  wrap.result.sgcca = wrapper.sgcca(data = A, design = C, penalty = rep(1, length(A)),
    ncomp = c(2, 2, 2,2), scheme = "centroid", verbose = FALSE)
  
  ##### visualization
  col &lt;- rep(c("blue", "red", "darkgreen", "darkviolet"))
  
  plotVar(wrap.result.sgcca, col=col, comp = c(1,2), 
    block = c(1,2,3,4), ncomp.select = c(1,2), labels = TRUE)
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/y2g0H.png" alt="Correlation circle plot"></p>
  
  <p>In this plot, I have managed to color the blocks in unique colors. I would also like to represent the columns using shapes. For instance, when we consider the different column names of the dataset mtcars</p>
  
  <pre><code>colnames(mtcars)
  [1] "mpg"  "cyl"  "disp" "hp"   "drat" "wt"   "qsec" "vs"   "am"   "gear" "carb"
  </code></pre>
  
  <p>According to the blocks I have split a(columns1:3), b(columns(4:6), c(columns 7:9), d(columns 10:11), I would like columns 1, 4, 7,10 to have same shapes (say circle), columns 2,5,8,11 (say square), columns 3,6,9 (say star). I tried setting the pch values but failed to produce the shapes according to column names in this plot. Could someone help me out here? Thanks</p>