Unicode strings and Mantid Tables

Bugs
1

Expected behavior

I can access a table column as a list with the syntax MyTable.column[“f0.A”], even if writing code that is Python 3 compatible

Actual behavior

An error from Mantid that it doesn’t like Unicode strings as column headers:

TypeError: No registered converter was able to produce a C++ rvalue of type int from this Python object of type unicode
  File "<string>", line 14, in <module>

Steps to reproduce the behavior

Create a table (for example a results table from Muon Analysis)
Open a new script tab in Workbench. Add the following after the standard headers (change the actual table and column names as appropriate):

tab=mtd["ResultsTable"]
colY=tab.column("f0.A")
print (colY)

Note that removing the “unicode_literals” from the future statement makes the script work as intended.

Platforms affected

Workbench 4.2 (found on Windows, probably all platforms)

2

This should be fixed when Mantid is upgraded to Python 3. I have still raised an issue in case we get a chance to fix this: Unicode not supported for Column access to TableWS · Issue #27555 · mantidproject/mantid · GitHub

3

The work around for now seems to be
colY=tab.column(str("f0.A"))
I think this will still work as intended in real Python 3.

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