How to remove quotation marks from InputString?

Question

I want to make a script for solving liniar equations (in Mathematica) with something like:

Solve[{InputString["Solving Linear Equations"]}]

The output is similar to:

Solve[{"x+y+z==0,x+y+z==0,x+y+z==0"}]

I want to remove the quotation marks. Is there a way to do this?

Try this: Solve[ImportString["{" <> InputString["Solve Equations:"] <> "}", "Package"], {x, y, z}]. — J. M.'s missing motivation, Nov 15 '17 at 15:59
It's a good idea to look at the related functions in the documentation, in particular Input (and the tutorial). — Szabolcs, Nov 15 '17 at 15:59
"Doesn't work" is very vague and does not give me much to diagnose. What did you input, what error messages did you get, what did the result (in InputForm[]) look like... now those would be more helpful information to have. — J. M.'s missing motivation, Nov 15 '17 at 16:14
I've entered x+y+z==0 three times. The error message is Solve::naqs: x+y+zï:f290[PlusMinus]0&&x+y+zï:f290[PlusMinus]0&&x+y+zï:f290[PlusMinus]0 is not a quantified system of equations and inequalities.
(https://imgur.com/VMOt2qk) — Andrei Paciurca, Nov 15 '17 at 16:22
Something's weird with your setup, if it's suddenly inserting \[PlusMinus] at weird places. — J. M.'s missing motivation, Nov 15 '17 at 16:25

score 2 · Answer 1 · answered Nov 15 '17 at 23:09

Just for fun, here is a way to do it with AskFunction.

solver =
  AskFunction[
    Solve[Ask["equations" -> "Expression"], Ask["variables" -> "Expression"]]];

solver[]

{{x -> 2/3, y -> 1/3}}

Note: This has the advantage that you don't have to convert strings to expressions and the disadvantage requiring an internet connection to convert the textual inputs into Mathematica expressions.

score 0 · Accepted Answer · answered Nov 15 '17 at 16:23

0

Solve[ToExpression@
  StringSplit[InputString["Solving Linear Equations"], ","]]

Paste in x+y+z==0,x+y+z==0,x+y+z==0

{{z -> -x - y}}

answered Nov 15 '17 at 16:23

Chris Degnen

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Always be wary of using ToExpression blindly. For your code, a user could enter something like Print["deleting files"], DeleteFile /@ FileNames["*"] at the prompt. – Jason B. Nov 16 '17 at 17:33

How to remove quotation marks from InputString?

2 Answers2