Thinking over my initial reply above, I realized a few things:
- In order to get a really good and proper histogram over unicode text, you'd want to be able to see not only how many times each character occurs, but also which "charts" (which language/function subgroups of unicode characters) are represented in the data, and what their respective frequencies are.
- Getting a proper histogram of that sort involves a fair bit of drudgeful coding and looking up all the details about what the various "charts" really are (their names and the characters they contain); just telling someone "you should try doing that" is sort of infelicitous, bordering on rude.
- I've really been wanting to have just such a tool myself for some time now, and it's about time I got around to that.
So here it is:
unichist -- count/summarize characters in data. (I've tested most of its functionality, but not all of it...)