Re: Re: Color coding a Table entry
- To: mathgroup at smc.vnet.net
- Subject: [mg92702] Re: [mg92688] Re: Color coding a Table entry
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sat, 11 Oct 2008 06:42:07 -0400 (EDT)
- Reply-to: hanlonr at cox.net
For plots use ColorFunction
Plot[(x - 1) (x - 4), {x, 0, 5},
ColorFunction -> Function[{x, y}, If[y < 0, Blue, Red]],
ColorFunctionScaling -> False]
Bob Hanlon
---- AES <siegman at stanford.edu> wrote:
=============
Original post:
> I'm Printing (to the screen) a Table like, let's say,
>
> Table[{f1, f2, f3}, (x, xmin, xmax}]
>
> and anytime the value of f2 goes negative I want that value printed in
> Red. What's a simple, compact way to code this?
Of the dozen or so replies, I'd say that
> Table[{f1, Style[f2, If[f2 < 0, Red, Black]], f3}, {x, -1, 5}]
>
>
> Bob Hanlon
is by far the best: simple, clean, you can see what it does, no arcane
symbols, no cross effects on anything else outside that entry (and, the
solution I'd already come up with on my own).
If the conditional in the If[ ] statement got lengthy, to avoid
cluttering up the Table with it I might go to the alternative suggestion
> redneg[expr_] := If[cond[expr], Style[expr, Red], expr, expr]
>
> With[{xmin = 0, xmax = 10},
< Table[{f1, redneg[f2], f3}, {x, xmin, xmax}]]
<
> Regards, Jean-Marc
Or, just define the conditional separately, outside the Table,
cond[expr_] : = <<something>>
and use
Style[f2, If[fcond[f2], Red, Black]]
in the Table.
Would Plot[redneg[f[x]], {x, xmin, xmax}] make the plot turn black
below the x axis??? Have to try it and see . . .
--
Bob Hanlon