Frequently-Asked Questions


How can I make CLIChart run faster?

a) Install Psyco to speed up Python scripts

Psyco is a Just-In-Time compiler for Python. The CLIChart Python-based tools (linestats, discretestats, mid and aggregate) will use psyco if it’s installed, and this should speed up their operation when larger amounts of data are involved.

b) Use a Later Version of Java

The main clichart program runs under Java. Later versions of Java are likely to make it start and/or run faster. Java 1.4 is particularly slow - if you’re still on 1.4, you should think very seriously about upgrading.

Running Under Windows

Why do I get an ‘invalid file descriptor’ error when piping data to a tool?

If you get a stack trace (complaining about an ‘invalid file descriptor’) when piping data into one of the Python-based tools (linestats, discretestats, mid or aggregate), this is due to a bug present in some versions of Windows.

The bug presents when you pipe data into a script that was launched based on a file extension, so for example it occurs in the first case below but not the second. Note that you must have python.exe in your PATH for the second example to work:

rem This may fail, depending on the Windows bug
... |

rem This should always work (if python.exe is in your PATH)
... | python

See for details of the bug