[SYSTEMDS-2537] Improve the consistency of predicates in "If-then-else" expressions

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: SystemML 0.13
• Fix Version/s: Not Applicable
• Component/s: Parser
• Assignee: Unassigned
• Reporter: Raymond Tay
• Created: 19/Mar/20 05:56
• Updated: 26/Mar/20 08:55
• Resolved: 26/Mar/20 08:55

Description

The predicate or conditional-expression in the evaluation of the If-expression allows literal numeral values to be part of the predicate. In the parser, if it sees a literal value of 1 then it would be true otherwise it is false; however it is entirely plausible to extend that definition to cover all values > 0 to be true otherwise values < 0 will be interpreted as false.

E.g. this should print No! but instead it prints "Yes!"

scala> val s = dml(""" if(-42) print("Yes!") else print("No!") """)

scala> ml.execute(s)

Yes!

SystemML Statistics:

Total execution time: 0.012 sec.

Number of executed Spark inst: 0.

res0: org.apache.sysml.api.mlcontext.MLResults = None

Issue Links

• links to: GitHub Pull Request #868