## documentation bug?

Mathematica

### Next

• 1. Inputting Dynamic Variables
I am trying to organize a set of dynamic variables that can be modified either by using an input field or by updating the variables from a file. When updating from a file I use a button. I have a large number of variables although in the toy example below I just give 3. The modules will end up in a private context. The idea below is that the function pp[] contains a list of all the variables in a held form. The list named vals can be obtained by reading from a file with new values updated from new files. Below I give an example that works. However, there must be a better way... Having a ClearAll in a button seems a poor method for getting back to symbols rather than values. Any suggestion for a better approach.? ReSet[] := DynamicModule[{}, Dynamic[TableForm[ Table[InputLine[pp[][[i]]], {i, Length[iv]}] ]] ] InputLine[{p_, q_}] := DynamicModule[{t}, ReleaseHold[ Row[{p, InputField[Dynamic[t]]}] /. t :> q] ] ButtonReSet[] := Button["New values", Module[{aa, bb}, ClearAll[a, b, c]; aa = ReleaseHold[pp[][[All, 2]]]; bb = pp[][[All, 1]] /. vals; Evaluate[aa] = bb;]] F[] := DynamicModule[{}, Dynamic[Plot[a x^2 + b x + c, {x, -1, 1}]] ] ClearAll[pp, a, b, c]; iv = {a, b, c}; pp[] := {{"coff a ", Hold[a]}, {"coff b ", Hold[b]}, {"coff c ", Hold [c]}}; vals = {"coff a " :> 2, "coff b " :> 3, "coff c " :> 4}; Dynamic[#] & /@ iv ReSet[] F[] ButtonReSet[]
• 2. How reliable are mathematica's special functions? (Hypergeometric and
I don't know if WRI will divulge anything about their algorithms for numerical approximation of Hypergeometric functions. Can I trust it? Mathematica 6.0 can handle AppelF1[1.6+.6] say, but Mathematica 7.0 won't even give an actual number (this is a problem all up the diagonal after a certain point. The problem occurs with parameters roughly as follows: AppellF1[1/2, .3, .3, 1/4, -100 z^4, z^4]; One: Before I try and figure out more of the nature of the function at different points, can anyone tell me if there are known problems with mathematica's special functions being reliable? Two: Given that I want to plot this function in a portion of the plane, can I have Mathematica overlook these sets of non-computable (by mathematica) points, and still get a plot? Thanks, Janey.
• 3. upwind scheme in Mathematica?
hi all, I am trying to solve convection-diffusion-reactions(in time and one space coordinate) equations with NDSolve. Most of the time I am not getting solution to my problem as solver fails to converge. I guess the problem is very stiff and convection dominated. When I use upwind difference scheme in fortran, I get the solution easily. How can use upwind in NDSolve? What is the method mathematica uses to solve pdes? any comments are welcome. Thanks in advance.

### documentation bug?

```DataRange is listed as new in "5.1" according to Wolfram's 7.0
documentation.  I think this is incorrect. I'm using V5.2 (required for
webMathematica), and this option is not available. Does anyone confirm?

```

### Re: documentation bug?

```>From my Mathematica 5.2 I get
In:=??DataRange

DataRange

but I get no information from the help browser.

2009/7/23 Scot Martin < XXXX@XXXXX.COM >

```