MathGroup Archive 2014

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

Search the Archive

Re: Chained-functional notation examples?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg132703] Re: Chained-functional notation examples?
  • From: Daniel Lichtblau <danl at wolfram.com>
  • Date: Fri, 9 May 2014 02:06:07 -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> <000901cf6ac8$b3fb5470$1bf1fd50$@cox.net>

On 05/08/2014 09:20 AM, Hans Michel wrote:
> 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

Hans et al,

You are correct, I was using an unreleased version. Actually some good
came of it (I found a weakness in date comparisons that got addressed).
I'll leave modification for versions <=9 to others more adept at this
sort of thing. I never was much good with dates...

As for baseball,

http://www.redreporter.com/2012/2/13/2796324/hus-on-first-a-modernization

Daniel


> -----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: 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: parametric and analytical geometry
  • Next by Date: Re: Chained-functional notation examples?
  • Previous by thread: Re: Chained-functional notation examples?
  • Next by thread: Re: Chained-functional notation examples?