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.

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5/6/2014 6:26:46 AM

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"

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5/7/2014 6:45:05 AM

Am Dienstag, 6. Mai 2014 08:26:46 UTC+2 schrieb Unknown: > 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. Well, I think that postfixing by use of the Mathematica Postfix operator "//" accompanied by use of Mathematica pure Function "&" with access to the last result = by using Mathematica Slot "#" (argument to the pure Function) mimics *nix piping best: the following gets all files of "c:/temp" in all sub dirs older than 200 days containing at least one of the strings "str1", "str2" : "c:/temp" // FileNames["*", #, Infinity]& // Select[#, DateDifference[FileDate[#], DateList[]] > 200 &]& // Select[#, StringMatchQ[#, "*str1*"] || StringMatchQ[#, "*str2*"]&] & Regards Robert

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5/9/2014 6:06:05 AM

On 5/6/14 at 2:26 AM, dog@gmail.com (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. If you are looking for a system with one way to achieve a given goal, Mathematica isn't it. There are multiple ways of achieving a result without using dif...

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 +0...

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 +0...

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 +0...

On 5/7/14 at 2:44 AM, dog@gmail.com (Unknown) wrote: >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" It is not entirely clear what it is you are trying to do. There are a couple of ways to obtain a list of files in a given directory. First, if the directory is the current working directory, then FileName[] will return a list of every thing at the top level of the directory. But in this case, only the...

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Hello, I've created simple procedure in another system, which takes one parameter (x(1)) as argument function and returns one value. After compilation, with 'mex -l fnc.m' command I've created a shared library. In Mathematica's script I load this function with: link = Install["f:\\f1.exe"]; F1[0.5] # I have a correct result Then I define such argument, which are part of a function fCE=F1[x1]; f C[{x1_}]=fCE; and execute the Mathematica function FNC[...,fC,...]. The FNC is defined as follow FNC[...,fC_,...]:=Block[{..., fCi,...,cog,} ..... bv...

hi, What I want to do is to : Plot Reflectivity: Refelectivity is an expression ( or a function ) depending on nfilm which in turn depends on epsmodel( which in itself is a function of 3 parameters and a variable ) therefore : epsmodel = f(a,b,c,d,x) (* result is a comlpex number *) nfilm = sqrt[epsmodel] reflectivity = ((nfilm - 1) / (nfilm +1))^2 I just want to plot reflectivity and see the variation in it when (a,b,c,x) varies ( using the Manipulate[] tool ) Please let me know how to do this in term of these functions ? the exact formalism for which I got the err...

Dear All, I am fairly new to mathematica. I am stuck with a problem I cannot solve. I would like to call a previous equation into the function Function. If a type directly the expression or copy paste it, it works. However, when I call the expression by its name it does not. Here is the code for a more precise explanation: In: ll Out: d + a x + h x^2 + b y + e x y + c z + j z^2 In: Function[##, a x + b y + c z + d + e x y + h x^2 + j z^2] & @@ {Listp} Out: Function[{a, b, c, d, e, h, j}, a x + b y + c z + d + e x y + h x^2 + j z^2] It works well and I can use it to genera...

On 8/1/10 at 4:58 AM, camille.segarra@gmail.com (Camille) wrote: >I am fairly new to mathematica. I am stuck with a problem I cannot >solve. I would like to call a previous equation into the function >Function. If a type directly the expression or copy paste it, it >works. However, when I call the expression by its name it does not. >Here is the code for a more precise explanation: > >In: ll Out: d + a x + h x^2 + b y + e x y + c z + j z^2 >In: Function[##, a x + b y + c z + d + e x y + h x^2 + j z^2] & @@ >{Listp} Out: Function[{a, b, c, d, e, h, ...

Hi, In Wolfram Workbench, I'm running a Java app that's working ok with the generic import import com.wolfram.jlink.*; , and it will execute basic functionality like evaluate, getInteger, etc. But I can't seem to execute any of Mathematica's Boolean functions. Can't use BooleanConvert, nor BooleanFunction, nor BooleanMinimize, or any of the related methods. Does anyone know how to access these? I'm using createKernelLink(). ...

I've update my Mathematica history table with a new listing of Mathematica 7 functions (not just the symbols). These are anything in Mathematica System context which has the form name[...] I want to thank John Fultz for his hint in another posting in this newsgroup to use the Usage message from ? and look for anything that starts with this pattern. I obtain 1869 functions. Since what I find is somewhat less what it is supposed to be (close to 2,500) according to WRI blog here http://blog.wolfram.com/2008/11/18/surprise-mathematica-70-released-today/ I could only sug...

hi, What I want to do is to : Plot Reflectivity: Refelectivity is an expression ( or a function ) depending on nfilm which in turn depends on epsmodel( which in itself is a function of 3 parameters and a variable ) therefore : epsmodel = f(a,b,c,d,x) (* result is a comlpex number *) nfilm = sqrt[epsmodel] reflectivity = ((nfilm - 1) / (nfilm +1))^2 I just want to plot reflectivity and see the variation in it when (a,b,c,x) varies ( using the Manipulate[] tool ) Please let me know how to do this in term of these functions ? the exact formalism for which I got the error : ...

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