title: How to set the color range of scale_colour_brewer() in ggplot2? (palette selected)
body: <p>I am sorry I cannot offer an image because of limited reputation I have on this site...</p>
  
  <p>I used the following code to generate my line chart in R:</p>
  
  <pre><code>p &lt;- ggplot()+
  geom_line(data=data, aes(x, y, color=Label))+ scale_colour_brewer(palette="Oranges")
  </code></pre>
  
  <p>I used the palette"Oranges" because I want to generate a series of lines with similar while different colors. </p>
  
  <p>However, the color of lower/upper range is too light, so I want to set a limit for the palette to avoid whitish colors. </p>
  
  <p>I know I should specify something like <code>scale_color_gradient(low = "green", high = "red")</code>, but how can I find the specify color with a given palette?</p>
  
  <p>Many thanks!</p>