Re: Chained-functional notation examples?
- To: mathgroup at smc.vnet.net
- Subject: [mg132704] Re: Chained-functional notation examples?
- From: "Hans Michel" <hmichel at cox.net>
- Date: Fri, 9 May 2014 02:06:27 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- Delivered-to: l-mathgroup@wolfram.com
- Delivered-to: mathgroup-outx@smc.vnet.net
- Delivered-to: mathgroup-newsendx@smc.vnet.net
- References: <zLEb1n00r1r5Uyi01LEcLm>
Daniel: Now What's the catch with Today? Today will only work in Wolfram Language (Mathematica v 10), which may be officially released Tomorrow? One can go on with a Who's on First theme. (Goes along with W|A baseball data) But currently the DateObject "Today" would have to be changed to something that would work in Mathematica 9 or below. Hans -----Original Message----- From: Daniel Lichtblau [mailto:danl at wolfram.com] Sent: Thursday, May 08, 2014 3:08 AM To: mathgroup at smc.vnet.net Subject: [mg132704] Re: Chained-functional notation examples? A query such as this might do what you have in mind. Here directoryname should be changed to whatever directory you want searched. Select[FileNames[("*uid*" | "*UID*"), directoryname, Infinity], ((StringMatchQ[DirectoryName[#] , "*egal*"] && Today < DayPlus[FileDate[#], 3]) &] Also there is a case sensitive switch if you want to allow strings with e.g. "uID". If you want to allow that uid only in the name and not full string Daniel Lichtblau Wolfram Research ------------------- On Tue, 06 May 2014 06:26:46 +0000, Unknown wrote: > I came to 'Mathematica' via Xahlee's criticism of the ad-hoc nature of > unix-piping [functional notation]. He claims [& I believe him] that > Mathematica has a better, more consistent notation. But the facility of > PRE, IN & POST-fix alternatives, seems bad. You want ONE way of > acieving the goal. More rules just increases mental load. > > A major benefit of functional [unix-piping] programming style, is that > you don't need to remember the-full-journey: you just need to remember > the previous stage's output. Nor do you need to remember several names: > the previous output is just "it". A superficial read through a recent > article[s] here, about <collecting data from several servers, and > agregating it, and sending the result to a master> seemed very > interesting, and matches my ideas of using functional programming. But > I can't afford to invest in ANOTHER notation/syntax, without good > prospect of productivety increase. > > Just as a test, how would Mathematica handle the following [or part of] > little task: > > search all files in Dir=tree D | > which are less than N days-old | > and which contain string S1 | > and which contain string S2 . > > Actually, this seems not a good example, since it's biased towards the > *nix file system's format/syntax. > > Try: > Search in table of ListOfOpenFiles for lineS with path-P [field] | > which have same tty-field as line with path-P2 & program-M [field] > > This sounds like a data-base problem? > > Or is there a nice list of 'such' Mathematica examples? > > Thanks, > > == John Grant. Here's a related real-live problem: list all files in Dir-tree:D | which are less-than daysOld:N | and contain "egal" in the FullPathName | and contain String:"uid" OR "UID"