Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2014

[Date Index] [Thread Index] [Author Index]

Search the Archive

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"




  • Prev by Date: Re: Chained-functional notation examples?
  • Next by Date: Re: Chained-functional notation examples?
  • Previous by thread: Re: Chained-functional notation examples?
  • Next by thread: Re: Chained-functional notation examples?