(Updated November 3, 2014 mentioning Canopy 1.5 Preference option.)
To increase the length of your ipython (qtconsole) buffer
In Canopy 1.5 and above, this can be configured from the Canopy Preferences dialog (Python tab).
Canopy's IPython panel is an IPython QtConsole.
By default, QtConsole's scrollback buffer only holds the most recent 500 lines. This can be increased as follows:
1. As described in this section of the IPython documentation, locate the IPython configuration directory. By default, it is located here:
On Windows Vista, 7, or 8:
On OS X or Linux:
2. Locate the "profile_default" subdirectory of the IPython configuration directory. If it doesn't exist, create it by typing the following command at a Windows Command Prompt or OSX/Linux Terminal window:
ipython profile create
3. Look for the file "ipython_config.py". If it does not already exist, create it as just described.
4. Edit this file, and add the following line to the end:
c.IPythonWidget.buffer_size=1000 (or whatever number you prefer).