title: How to make violin plot using ggplot with no column for a y variable?
body: <p>My dataframe just has columns that I want to create into violin plots but without specifying a y value. </p>
  
  <p>Each column is a different datasubet showing an average rate of evolution (so really the y column should be created automatically). Almost all examples using ggplot use the car dataset where you specify the x column and y column that already exists in the dataframe.</p>
  
  <p>Example of my dataframe:</p>
  
  <pre><code>Species  Zone1   Zone2   Zone3   Zone4
  cf       0.0045  0.040   0.054    0.089
  cx       0.12    0.145   0.098    0.095
  cy       0.044   0.067   0.051    0.077
  </code></pre>
  
  <p>I want to make violin plots where the x axis has Zone1, Zone2, Zone3, and Zone4 and the y-axis are just the evolutionary rate values.</p>
  
  <p>I am able to do this using the vioplot package but I want to keep my script using tidyverse and ggplot since I like it's added features more. But I cannot figure out how to transform my data to get what I need it show.</p>
  
  <p>I've tried:</p>
  
  <pre><code>ggplot(my_data, aes(x=c(Zone1, Zone2, Zone3, Zone4), 
          y=c(Zone1, Zone2, Zone3, Zone4)) + geom_violin()
  </code></pre>
  
  <p>But this has too many arguments...Not sure what to do for the y variable.</p>