Opened 13 years ago
Closed 13 years ago
#1955 closed defect (duplicate)
bug in vector
Reported by: | was | Owned by: | somebody |
---|---|---|---|
Priority: | blocker | Milestone: | sage-duplicate/invalid/wontfix |
Component: | basic arithmetic | Keywords: | |
Cc: | Merged in: | ||
Authors: | Reviewers: | ||
Report Upstream: | Work issues: | ||
Branch: | Commit: | ||
Dependencies: | Stopgaps: |
Description
Hi, It seems the __abs__ method for vectors is missing the part that is supposed to square the components before they are added. [e.g. abs(vector([1..5])) should really be sqrt(1+4+9+16+25)=sqrt(55) ] The code of the current version is included below. def __abs__(self): """ Return the square root of the sum of the squares of the entries of this vector. EXAMPLES: sage: v = vector([1..5]); abs(v) sqrt(15) sage: v = vector(RDF, [1..5]); abs(v) 3.87298334621 """ return sum(self.list()).sqrt() The last line should be something like return sum([x*x for x in self.list()]).sqrt() (not sure if that is the most efficient way). --Peter
Change History (1)
comment:1 Changed 13 years ago by
- Milestone changed from sage-2.10.1 to sage-duplicate/invalid
- Resolution set to duplicate
- Status changed from new to closed
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This is a dupe of #1954, which already has a patch for review.