title: Scatter plot with same color for values below a threshold
body: <p>I am trying to generate a scatter plot of coordinates(x,y) where the color is decided by a value ranging between (-3,1.5). How do I plot all the points with value less than -1 with same color without them being omitted from the plot all together. I tried to use <code>im.set_clim(-1,1.5)</code> , but it cutoff the values below -1 and didn't plot.</p>
  <p>How do I do this?</p>
  <p>A follow up question :</p>
  <p>Is it possible to have sequential colormap where the values below -1 are all red (no gradient) and above -1 are having a sequential colormap which does not start with a shade of red.</p>