Hatched shading?
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From: E. Martin-Serrano on 21 Jul 2010 07:12 Hi, Yes. Using your code I also got two protruding red lines, one in each blue plot. Version: {7.0 for Microsoft Windows (32-bit), Release: 1} E. Martin-Serrano -----Original Message----- From: ADL [mailto:alberto.dilullo(a)tiscali.it] Sent: Tuesday, July 20, 2010 9:42 AM Subject: Re: Hatched shading? Following what Bob brilliantly suggested, I found a possible bug in Mathematica 7.0.1 for Windows. If you type the following, you will get a couple of red lines getting out of their boundary: f[x_] := Sin[x]; Plot[ {Table[(x - k)/3, {k, -3, 3, .10}], f[3x]}, {x, 0, 3}, PlotRange -> {0, 1}, RegionFunction -> Function[{x, y}, 0 < y <= f[3x]], PlotStyle -> { Directive[ AbsoluteThickness[4], Red], Directive[ Thick, Blue] } ] Does anybody else confirms this? ADL On 18 Lug, 07:06, Bob Hanlon <hanl...(a)cox.net> wrote: > I forget to copy the definition of f[x] that I was using as an example > > f[x_] = Exp[-x] > > Bob Hanlon
From: Bob Hanlon on 21 Jul 2010 07:13 I see similar artifacts on a Mac. Playing with PlotPoints can stop this $Version 7.0 for Mac OS X x86 (64-bit) (February 19, 2009) f[x_] := Sin[x]; Plot[{ Table[(x - k)/3, {k, -3, 3, .10}], f[3 x]}, {x, 0, 3}, PlotRange -> {0, 1}, RegionFunction -> Function[{x, y}, 0 < y <= f[3 x]], PlotStyle -> { Directive[AbsoluteThickness[4], Red], Directive[Thick, Blue]}, PlotPoints -> 40] Bob Hanlon ---- ADL <alberto.dilullo(a)tiscali.it> wrote: ============= Following what Bob brilliantly suggested, I found a possible bug in Mathematica 7.0.1 for Windows. If you type the following, you will get a couple of red lines getting out of their boundary: f[x_] := Sin[x]; Plot[ {Table[(x - k)/3, {k, -3, 3, .10}], f[3x]}, {x, 0, 3}, PlotRange -> {0, 1}, RegionFunction -> Function[{x, y}, 0 < y <= f[3x]], PlotStyle -> { Directive[ AbsoluteThickness[4], Red], Directive[ Thick, Blue] } ] Does anybody else confirms this? ADL On 18 Lug, 07:06, Bob Hanlon <hanl...(a)cox.net> wrote: > I forget to copy the definition of f[x] that I was using as an example > > f[x_] = Exp[-x] > > Bob Hanlon
From: David Park on 21 Jul 2010 07:14 The problem with RegionFunction is how many points does Mathematica use, especially with a straight line, and how does the algorithm determine where the boundary should be. Suppose one point is well within the region and the next point is well without. I'm sure that Mathematica doesn't calculate the exact intersections with boundaries. So I think the only reliable method is to use some brute force and trim the lines if they extend outside the region. Again, here is a Presentations solution where it is convenient to treat the hatching and the curve separately. Needs["Presentations`Master`"] f[x_] := Sin[x]; Draw2D[ {(* Draw hatch lines first *) Table[ Draw[(x - k)/3, {x, -1.5, 3}, RegionFunction -> Function[{x, y}, 0 < x < 3 \[And] 0 <= y <= f[3 x]], PlotRange -> {{1, 3}, {0, 1}}, PlotPoints -> 200, PlotStyle -> Directive[AbsoluteThickness[2], Red]] /. {x_?NumberQ, y_?NumberQ} :> If[0 < x < 3 \[And] 0 <= y <= f[3 x], {x, y}, Unevaluated[Sequence[]]], {k, -3, 3, .1}], (* Draw the curve without a fill *) Blue, AbsoluteThickness[2], Draw[f[3 x], {x, 0, 3}, PlotRange -> {0, 1}] }, AspectRatio -> .6, PlotRange -> {{0, 3}, {0, 1}}, PlotRangePadding -> {.1, .05}, Axes -> True, ImageSize -> 400] If you do the same graphic with say 25 points you will see that Mathematica did not always use points very close to the boundary. David Park djmpark(a)comcast.net http://home.comcast.net/~djmpark/ From: ADL [mailto:alberto.dilullo(a)tiscali.it] Following what Bob brilliantly suggested, I found a possible bug in Mathematica 7.0.1 for Windows. If you type the following, you will get a couple of red lines getting out of their boundary: f[x_] := Sin[x]; Plot[ {Table[(x - k)/3, {k, -3, 3, .10}], f[3x]}, {x, 0, 3}, PlotRange -> {0, 1}, RegionFunction -> Function[{x, y}, 0 < y <= f[3x]], PlotStyle -> { Directive[ AbsoluteThickness[4], Red], Directive[ Thick, Blue] } ] Does anybody else confirms this? ADL On 18 Lug, 07:06, Bob Hanlon <hanl...(a)cox.net> wrote: > I forget to copy the definition of f[x] that I was using as an example > > f[x_] = Exp[-x] > > Bob Hanlon
From: Alexey Popkov on 21 Jul 2010 07:10 Hello, I confirm this behavior on Windows XP SP3 with Mathematica 7.0.1. All the red lines get out of the region defined by RegionFunction. "ADL" <alberto.dilullo(a)tiscali.it> news:i23k1u$eqc$1(a)smc.vnet.net... > Following what Bob brilliantly suggested, I found a possible bug in > Mathematica 7.0.1 for Windows. > If you type the following, you will get a couple of red lines getting > out of their boundary: > > f[x_] := Sin[x]; > > Plot[ > {Table[(x - k)/3, {k, -3, 3, .10}], f[3x]}, > {x, 0, 3}, > PlotRange -> {0, 1}, > RegionFunction -> Function[{x, y}, 0 < y <= f[3x]], > PlotStyle -> { > Directive[ AbsoluteThickness[4], Red], > Directive[ Thick, Blue] > } > ] > > Does anybody else confirms this? > > ADL > > > > On 18 Lug, 07:06, Bob Hanlon <hanl...(a)cox.net> wrote: >> I forget to copy the definition of f[x] that I was using as an example >> >> f[x_] = Exp[-x] >> >> Bob Hanlon >
From: Themis Matsoukas on 22 Jul 2010 05:43
I get an error. What am I missing? Get::noopen: Cannot open Presentations`Master`. >> Needs::nocont: Context Presentations`Master` was not created when Needs was evaluated. >> $Failed Themis |