[Pkg] The Trunk: Collections-ul.450.mcz
commits at source.squeak.org
commits at source.squeak.org
Mon Jul 25 09:22:10 UTC 2011
Levente Uzonyi uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-ul.450.mcz
==================== Summary ====================
Name: Collections-ul.450
Author: ul
Time: 25 July 2011, 1:37:20.234 am
UUID: 2d09bd44-bfdf-1840-87cb-81ced69f9948
Ancestors: Collections-nice.449
Avoid a multiplication, use low level methods in
SequenceableCollection >> #polynomialEval: for better performance.
=============== Diff against Collections-nice.449 ===============
Item was changed:
----- Method: SequenceableCollection>>polynomialEval: (in category 'enumerating') -----
polynomialEval: thisX
- | sum valToPower |
"Treat myself as the coeficients of a polynomial in X. Evaluate it with thisX. First element is the constant and last is the coeficient for the highest power."
" #(1 2 3) polynomialEval: 2 " "is 3*X^2 + 2*X + 1 with X = 2"
+ | size sum valToPower |
+ sum := self at: 1.
+ (size := self size) = 1 ifTrue: [ ^sum ].
- sum := self first.
valToPower := thisX.
+ 2 to: size - 1 do: [ :ind |
- 2 to: self size do: [:ind |
sum := sum + ((self at: ind) * valToPower).
+ valToPower := valToPower * thisX ].
+ ^sum + ((self at: size) * valToPower)!
- valToPower := valToPower * thisX].
- ^ sum!
More information about the Packages
mailing list