Reporting NCL bugs

[Using ftp to upload data/scripts | Known bugs]

NCL has a long and successful track record of user support. The NCL project wants to help users but our time is valuable too!

The NCL project gets many statements/questions to the effect that "Something is wrong", "the results don't agree with ...", etc.

Most often the problems are due to users not reading the documentation.

Before sending us code, data, and image files:

  • Read and re-read the documentation for any functions being used.
  • Make sure data has the correct units required.
  • Make sure your data doesn't have unexpected missing values.
  • Carefully read any error messages.
There is no debugging "magic". We use simple procedures like print and printVarSummary to examine data. We examine a file's contents via "ncl_filedump" or "ncdump -h" ("ncdump" is for NetCDF files only). We suggest you do this also.

Only after doing the above should the script, data, and/or image files be sent.

  • Ideally, the NCL script is small and illustrates the problem.

    Some people send us scripts that contain large numbers of lines commented out. This makes it difficult for us to follow. Please clean up the code prior to sending scripts.

  • Since image files (e.g. PS files) can be large, please convert to (say) PNG or GIF. If possible, make the images available via the web.

You can ftp larger datasets and files to: 

ftp ftp.cgd.ucar.edu
anonymous
<use your email address for the password>
cd incoming
put ...
put ...
. 
. 
. 
quit
Send email to ncl-talk (you must subscribe first) with the following information:
  • The names of the files after you have successfully completed the transfer.
    We cannot look at the ftp/incoming directory for security reasons.
  • The version of NCL you are running (ncl -V).
  • The type of system you are on (uname -a).
  • The exact error message you are getting. If there is no error message, then a detailed description of the problem.

Thank you for your consideration.