How to Read This Function
- To: mathgroup at smc.vnet.net
- Subject: [mg45671] How to Read This Function
- From: "Bruce W. Colletti" <bcolletti at compuserve.com>
- Date: Sat, 17 Jan 2004 02:34:40 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Re Mathematica 5.0.
HelpBrowser/BuiltIn/AlgebraicComputation/FormulaManipulation/Assuming
has an example that uses
ff[a_?(Refine[# > 0] &)x_] := a*ff[x]
Thus, ff[2x] returns 2 ff[x] ("If $Assumptions has no effect on
ff...then ff pulls out positive numeric factors."
What's the right way to interpret the function's lefthand side? My take
is "Split the passed argument (#) into variables a and x, where a is the
product of all positive numeric factors and x is the product of what
remains." If this is correct, then I don't know for sure how the
lefthand side says this.
Must the argument be a product? If so, then how is the lefthand side
saying this?
Thanks.
Bruce