How to see the previous printed values in Python console

Question

I am printing some set of values in console and this is a program which runs for than an hour. There were run time warning in red during the run. However, when I scroll up to see them, they don't appear, as the program is running very fast displaying new values as it runs.

Is there any way for me to display only run time warnings alone or to see the entire values printed previously (as they are warnings, it does not stop the program from running)?

Answer 1

I don't know how you are "printing some set of values" in your console but if you are using the python logging module and your "warnings" are set with the WARN level (all your other stuff is INFO , or DEBUG etc) you can set the logger to only output for WARN and above ( ERROR and CRITICAL ).

import logging
logger = logging.getLogger('spam_application')
logger.setLevel(logging.WARN)

See more examples in the logging cookbook .

Another option is to set the history of your terminal (I don't know what you're using so can't give exact instructions) to store more lines of your command line.

Finally you could pipe the output to grep (if using a *NIX system) looking for warning or similar:

python your_script.py | grep warning