title: How to order a heatmap in R by x or y?
body: <p>I've created a heatmap on temperatures by city. ggplot orders cities by default, from Z-A, not what I want. How can I change the code so that the cities would be ordered A-Z, how overall x and y can be ordered in ggplot ?</p>
  
  <pre><code>ggplot(Cities, aes(x = Month, y = City, fill = AvgTemp, frame = City)) +
    geom_tile(color = "white", size = 0.5) +
    scale_fill_gradient(name = "Average Temperature",low = "blue", high = "red") +
    coord_equal() +
    labs(x = "Month", y = "", title = "Average Temp") +
    theme_tufte() +
    theme(axis.ticks = element_blank()) +
    theme(axis.text = element_text(size = 15)) +
    theme(plot.title = element_text(size = 15)) +
    theme(legend.title = element_text(size = 10)) +
    theme(legend.text = element_text(size = 10)) 
  </code></pre>