=====Histograms=====
IDL's histogram routine is very fast and useful, but it rounds improperly (try:

<code>
plot, histogram(findgen(60),nbin=20),ps=10
</code>
 
and you'll see).  Also, plotting the results of a histogram can be confusing, especially regarding the first and last bins.

For maximum ease of use, try the following routines:

  * {{:myhist.pro.txt|myhist.pro}} (you'll have to rename the file once you save it)
  * {{:histplot.pro.txt|histplot.pro}}

like this:
<code>
y=findgen(50)^2
h=myhist(y,nbin=10,x)
histplot,x,h
</code>

and see if you like them.  The /overplot flag on histplot allows you overlay histograms.  The basey keyword allows you to stack histograms by specifying the height of the bottoms of the various bins.