Bugfix: fix compute when called on empty lists

[geoffrey-g-delhomme]

What does this PR do?

Fixes #1218

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• Did you write any new necessary tests?

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[codecov]

Codecov Report

Merging #1219 (a89f121) into master (8086097) will increase coverage by 0%.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1219   +/-   ##
======================================
  Coverage      86%     86%           
======================================
  Files         191     191           
  Lines       11316   11318    +2     
======================================
+ Hits         9696    9698    +2     
  Misses       1620    1620           

[SkafteNicki]

Hi @geoffrey-g-delhomme,
Would it be possible to add a test for this case that are currently failing on master but will be fixed by this PR? :)