Wolfram Mathematica

William

01:30

Anyone around?

xzczd

@William Me？

William

@xzczd maybe you can help

Why doesn't this repeat replace multiple times

ReplaceRepeated[
 ReplaceRepeated[
  BoxData[
   RowBox[{"wget", " ", "-", "qO", "-", " ",
     RowBox[{"test", " ", "tacos"}]}]]
  , RowBox[{x__}] :> x
  ],
 BoxData[x__, " ", y___, " ", z__] :>
  BoxData[{x, " ",
    StringJoin[{"\"\<", y, "\"\<"}], " ",
    z}]
 ]

xzczd

@William The expected output is?

William

BoxData[{"wget", " ", "\"-qO-\"", " ", "\"test\"", " ", "tacos"}]

@xzczd

Its okay if you don't know, although it appears you do have more experience with M then I do.

xzczd

01:47

I'm trying to boil it down..

Ah, I see :)

After the second rule is used for once, the expression will become something with the pattern

BoxData[{__}]

so it no longer matches the rule

BoxData[x__, " ", y___, " ", z__] :>
BoxData[{x, " ", StringJoin[{"\"", y, "\""}], " ", z}]

William

Yes here is a simpler example that boils down the issue

ReplaceRepeated[
 BoxData["wget", " ", "-", "qO", "-", " ", "test", " ", "tacos"],
 BoxData[x__, " ", y___, " ", z__] :>
  BoxData[{x, " ",
    StringJoin[{"\"\<", y, "\"\<"}], " ",
    z}]
 ]

Oh dear god I think I see what you mean

xzczd

囧

William

So if I fix it like this

ReplaceRepeated[
 BoxData["wget", " ", "-", "qO", "-", " ", "test", " ", "tacos"],
 BoxData[x__, " ", y___, " ", z__] :>
  BoxData[x, " ", StringJoin[{"\"\<", y, "\"\<"}], " ", z]
 ]

it runs into a lot of issues

how might I fix it?

I hope you didn't freeze your computer

@xzczd

you still there

xzczd

02:04

Hmm... troublesome. StringTake seems not to notice the "\""

William

I'm thinking maybe pattern test could be used but I'm not sure.

Michael Hale

02:27

@William Are you just trying to surround the words in a string with quotes, except for the first and last?

William

@MichaelHale here is the actual question mathematica.stackexchange.com/questions/114666/…

I was trying to use the BoxForm of the expression instead of building a parser not sure it would work

Yes what you said is correct

xzczd

I think I know what to do, give me 3 minute!

Michael Hale

@William Not sure if this helps:

"wget -qO- \"http://google.com/line
   break\\\"\" $var" // StringSplit[#, " "] & //
  Replace[#,
    a_?(StringStartsQ@"$") :>
     ToExpression@StringDrop[a, 1], {1}] & // (ToExpression@First@#) @@
    Rest@# &

William

omg I'm not quit sure what you did

Michael Hale

Well it inserted some extra spaces before "break" when I pasted into chat.

William

02:40

@MichaelHale it doesn't work if you add a space inside the quotes

kinda defeats the purpose of the quotes

Michael Hale

Ah true

xzczd

OK after a long long 3 minutes I've finished a dirty one:

data = BoxData["wget", " ", "-", "qO", "-", " ", "test", " ", "tacos"];

pos = Flatten@Position[data, " "]

Replace[Flatten[
Apply[Replace[(Insert[#1, "\"", {{2}, {-2}}] &)[data[[#1 ;; #2]]],
BoxData[" ", a__, " "] :> {" ", StringJoin[a], " "}] &,
Partition[pos, 2, 1], {1}]], {b__, " ", " ", c__} :> {b, " ", c}]

Oh, I mean

William

Ideally my example should be generalizable to any number of arguments

xzczd

data = BoxData["wget", " ", "-", "qO", "-", " ", "test", " ", "tacos"];
pos = Flatten@Position[data, " "]
BoxData @@ Replace[
Flatten[Apply[
Replace[(Insert[#1, "\"", {{2}, {-2}}] &)[data[[#1 ;; #2]]],
BoxData[" ", a__, " "] :> {" ", StringJoin[a], " "}] &,
Partition[pos, 2, 1], {1}]], {b__, " ", " ", c__} :> {b, " ", c}]

William

@MichaelHale is there a split not for strings

BoxData["wget", " ", "-", "qO", "-", " ", "test", " ", "tacos"]

Michael Hale

02:44

@William You mean Split and SplitBy?

William

Split lists identical elements

Michael Hale

To be fair, your question just asked to support line breaks and quotes, lol

William

I'll give you the bounty if there are no other better answers, but being a shell I thought it was implied

I'll edit it

Michael Hale

@William SplitBy[{"a", " ", "b", "c", " ", "d"}, " " == # &]

William

Yes that works

Now I just need to remove {" "} and merge the remaining values

William

03:14

How do I remove all instances of the " " character

in a list

This is what I have so far

Map[(If[StringTake[#[[1]], 1] == "\"",
    StringJoin[#],
    StringJoin[{"\"", StringJoin[#], "\""}]
    ]) &,
 SplitBy[{"wget", " ", "-", "qO", "-", " ", "\"test\"", " ", "tacos"},
   " " == # &]]

@MichaelHale

Michael Hale

{"a", " ", "b", "c", " ", "d"} /. " " -> Nothing

{"a", " ", "b", "c", " ", "d"} // DeleteCases@" "

William

neither work

Map[(If[StringTake[#[[1]], 1] == "\"",
     StringJoin[#],
     StringJoin[{"\"", StringJoin[#], "\""}]
     ]) &,
  SplitBy[{"wget", " ", "-", "qO", "-", " ", "\"test\"", " ",
    "tacos"}, " " == # &]] // DeleteCases@"\" \""

nevermind

xzczd

03:32

@William Can't think out a solution to the original question. Just for curiosity, how did you transform the

wget -qO- "http://google.com/space line
break\"" $var

to BoxForm ?

I can't even finish this step

William

03:59

@xzczd I just did ctrl+shift+e on the current cell

Michael Hale

StringCases["wget -qO- \"http://google.com/  line
      break\\\"\" $var", {a : Shortest["\"" ~~ __ ~~ "\""] /;
     StringTake[a, {-2}] != "\\", Except[" "] ..},
   Overlaps -> False] //
  Map[If[StringStartsQ[#, "$"],
     ToExpression@StringDrop[#, 1], #] &] // (ToExpression@First@#) @@
    Rest@# &

William

give me a second and I'll post a working example

Michael Hale

Maybe that helps. Bed time for me.

William

Thank you I will definitely look into your example

Michael Hale

04:16

@William Oops. Can handle the $var to expression behavior in the first StringCases. Here is a simplification.

StringCases["wget -qO- \"http://google.com/  line
        break\\\"\" $var", {"$" ~~ a : Except[" "] .. :>
    ToExpression@a,
   a : Shortest["\"" ~~ __ ~~ "\""] /; StringTake[a, {-2}] != "\\",
   Except[" "] ..},
  Overlaps -> False] // (ToExpression@First@#) @@ Rest@# &

kirma

05:18

lmfdb.org - The L-functions and modular forms database

Saw this being advertised on both Tao's blog and a Numberphile video, so had to take a look at last.

Szabolcs

06:48

@xslittlegrass I also got that today.

J. M.

07:13

@kirma Very interesting; implementing these in Mathematica is possible, but very challenging (mathematically and programatically).

kirma

Frankly, for me, it's more like "there's some fancy stuff out there." I have trouble seeing any connection to anything I would be doing either professionally, or in the armchair mode. But it is sort of interesting.

justin

08:54

Hi Kirma could you help me with running Mathematica online using Wolfram Mathematica Online.

Karsten 7.

11:10

Today my M.SE editor buttons disappeared. Does anybody else have the same problem? I'm using a modified version of that script on Windows 10, Firefox or Pale Moon.

halirutan

11:24

@Karsten7. Yes, and I'm already aware of this issue.

Szabolcs

@Searke Do you know if LibraryFunctionLoad performance can be improved at all, at least in principle? What would be the best place to ask about this to get an informed answer? Support? W Community?

With ~200 functions to load, it is slow enough to be noticeable. On a Raspberry Pi it is very very slow, it takes about a minute to load my package, if I remember right.

But there is a big (> 2x) difference in performance between platforms, with OS X being the slowest. This suggests to me that the bottleneck is in platform dependent code which might be outside of the control of Wolfram developers ...

I should probably just implement lazy loading.

@P.Fonseca Any plans for the afternoon in Marseille?

P. Fonseca

@Szabolcs You mean, after the sessions?

Szabolcs

Yes.

Actually do you know what time they end?

P. Fonseca

@Szabolcs No. (planning and time). I can imagine an ending at around 17:00.

I'm open to any suggestion! I'm staying in Marseille for two nights.

picking the train to Nice, only on the 2nd, morning.

Szabolcs

11:39

Hm, there are more talks than I expected. I have my train back at 18:10.

Unfortunately couldn't take enough days off to go to Nice :-(

P. Fonseca

Well... I'll be working all time, except for my presentations...

Szabolcs

Unfortunately at my current workplace---for the first time---I don't get that sort of flexibility. :(

P. Fonseca

The balance between flexibility, and the actual possibility of actually taking a day off, is a difficult science... I would prefer to be able to take the day off... With the amount of holidays a French contract has, I typically have a few ones to spare...

Szabolcs

12:00

Does anyone know what the Package` context functions do?

J. M.

13:19

@kirma Apart from the Riemann hypothesis, there's still the BSD conjecture to be dealt with. So, a very active area of research. A good grasp of analytic number theory and complex analysis is the only barrier to entry. ;)

halirutan

14:18

@Mr.Wizard, @JasonB Someone around?

JasonB

Hey

I was gonna ask you about the chrome extension (which I love btw)

halirutan

I have fixed the bug in the editor buttons and the new version 1.3.8 should be available in the chrome store

3

@JasonB You had Chrome, right?

Can you check whether you get an update notification or whether it is easy to update the extension?

JasonB

Absolutely, just installed the new version but I probably need to restart chrome for the effect (can't just yet)
I had removed it earlier so I don't know about a notification

halirutan

@JasonB For me it was enough to just reload a page of SE

JasonB

Right you are

Thanks very much

My favorite is the In[] button

halirutan

14:22

@JasonB No problem at all. Have fun.

@JasonB Yep, that thing is quite handy.

JasonB

without it I keep turing the Out[] parts into quotes

Cheers

Searke

14:55

@Szabolcs I rarely know anything about *Link

Putting something on the wolfram community doesn't guarantee that a developer ever sees it

If were to send an email to tech support about this, I'm not sure what you'd be requesting.

A suggestion: "Since LibraryFunctionLoad can be really slow on Raspberry Pi, It'd be nice to have some method to lazily load functions"

a bug: " I think there's something wrong with LibraryFunctionLoad because it's 2x as slow on Mac"

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