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dh142 (1271) 35 Articles, 1236 Replies, 1271 Points
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Since 4/28/2012 1:09:00 AM, dh142 has written 35 articles and participated in 1236 conversations.
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dh142

dh142's articles:
 Items(35) /4 Next >> Last >| Debugger #2 4 44 (9/5/2008 6:09:29 AM) comp.soft-sys.math.mathematica Hello, I was trying to use the new Debugger and I do not find it very obvious to use. Astonishingly I could not find any descent manual or description. Here are some quirks I encoutered: To b...dh ConditionNumber 1 87 (6/10/2008 11:13:49 AM) comp.soft-sys.math.mathematica Hello, the entry in the manual about the condition number reads: "LinearAlgebra`MatrixConditionNumber[mat,Norm->p] p-norm approximate condition number of a matrix, where p may be 1, 2, or \[Infin...dh Vector valued differential equations 0 46 (4/21/2008 6:39:18 PM) comp.soft-sys.math.mathematica Hello, I lately asked if it is possible to write differential equations of vector valued functions without having to explicitely write all components. For the following cases it can be done very ...dh Defining derivatives #2 9 55 (4/18/2008 11:12:53 AM) comp.soft-sys.math.mathematica Hello All, does anybody know how to define symbolic derivatives. E.g.: f[x_]:=f1[x]; f'[x_]:=f2[x]; this does not work because f on the lefthand side is evaluated. To prevent this (do not fo...dh NDSolve and vector functions 3 61 (4/18/2008 11:11:28 AM) comp.soft-sys.math.mathematica Hello all, does anybody know a way to compute a vector valued function using NDSolve without explicitely specifying all vector components. Here is a simple example: Although NDSolve[{p'[t]==p[t],...dh Interpolation with vectors 4 50 (1/8/2008 11:42:44 AM) comp.soft-sys.math.mathematica Hello, under Interpolation you find in the manual: "Interpolation[{{x1,f1},{x2,f2}..}] The fi can be lists or arrays of any dimension." well, try an example: Interpolation[{{1,{1,1}},{2,{1,2...dh Rule that kills kernel #2 0 65 (1/8/2008 6:42:01 AM) comp.soft-sys.math.mathematica Hello, the following snipet worked well in version 5.1 but kills the kernel in version:6.0 for Microsoft Windows (32-bit) (June 19, 2007). This snipet replaces every InterpolationFunction by the ...dh Rule that kills kernel 0 57 (1/8/2008 6:28:36 AM) comp.soft-sys.math.mathematica Hello, Consider my previous post. In between I found that in version 6 a "HoldPattern" is needed: rules:=HoldPattern[x:InterpolatingFunction[_,_,{y_},__]]:>Evaluate[{#,x[#]}&]/@y; rules Howe...dh Bug in Print 0 47 (12/11/2007 1:33:40 AM) comp.soft-sys.math.mathematica Hello, consider: Graphics[Line[{{0,0},{1,1}}],PlotRange->{{0.6,0.75},{0.7,0.75}}] this plots a line and works fine. However, if we change xmin in the PlotRange command to: PlotRange->{{0.7,0.75...dh Zoom2D #4 0 56 (11/1/2007 10:48:14 AM) comp.soft-sys.math.mathematica Hello, since I posted the Zoom2D utility I got a few complains that it is not working properly with complicated graphics. The main problem seems that on clicking on a graphics you get a data str...dh

dh142's replies:
 Items(1148) /115 Next >> Last >| ListManipulationQuestion 2 62 (10/29/2008 10:47:53 AM) comp.soft-sys.math.mathematicaHi: I try to encode a hash table in the name of list. successors[{s_Integer, {{nhu_Integer, nhd_Integer}, {nlu_Integer, nld_Integer}}}] := { {1, {{nhu + 1, nhd}, {nlu, nld}}}, {1, {{nhu, nhd + ...xiaochu1 (2) plot problem #2 1 49 (10/29/2008 10:48:25 AM) comp.soft-sys.math.mathematicaHey folks, I'm new to Mathematica. I'm trying to set up a graph for the hydrogen 2s state. I just can't get it to work. The code as I have it is: This always generates errors. Part of the problem is th...mgcqso (5) odd delay problem 4 45 (10/29/2008 10:48:46 AM) comp.soft-sys.math.mathematicaI am running v. 6.0.3.0 I am having some weirdness where I will do something like: G=Array[f,100]; For[i=1, i<=100, i++, f[i] = some calculation] Then I will look at the result: ListLinePlot[G]...mmandelberg (14) 3D Graphics in a Palette or Dialog 11 62 (10/29/2008 10:50:10 AM) comp.soft-sys.math.mathematicaHi, I am trying to display a 3D graphic in a separate window from my main notebook. The idea is that as I'm editing the data driving the graphic (regardless of where I am in the notebook), I can still see...ggroup1 (153) Boundary problem with parameter using NDSolve 1 84 (11/3/2008 10:24:34 AM) comp.soft-sys.math.mathematicaDear friends, I hope you can help me with the following problem. I try to solve the Schr=F6dinger equation for some arbitrary potential V(x): -f''[x] + V[x]*f[x] == ee*f[x] Considering discrete energy... Data fitting from coupled differential equations 2 125 (11/3/2008 10:24:45 AM) comp.soft-sys.math.mathematicaHi, I'm working on a predator-prey model for 2-species: n1'[t] == a1 n1[t] - b1 n1[t]^2 + c1 n1[t] n2[t] n2'[t] == a2 n2[t] - b2 n2[t]^2 + c2 n1[t] n2[t] n1[0] == n10, n2[0] == n20 I have real data fo...margeorias (2) Eliminating common factors? 8 49 (11/3/2008 10:26:10 AM) comp.soft-sys.math.mathematicaI have a simple, totally algebraic symbolic calculation that displays its output in the form (rewritten here using TeX notation) 4 ( {a \over 4 } + { b \over 4 c } ) where a, b and c are fairly si...siegman (1558) Tooltip ans Sound - 2nd posting 7 44 (11/4/2008 11:19:02 AM) comp.soft-sys.math.mathematicaHello, I have found that Tooltip[obj1, obj2] evaluates obj2 upon a mouseover event on obj1. The objects can either be Text or Graphics, all combinations work. Here is my question: can I use a Sound as obj2...axel.kilian (8) Create a cumulative list 8 45 (11/4/2008 11:19:44 AM) comp.soft-sys.math.mathematicaHi to all, I have a problem creating a program in Mathematica and I can't find how to do it. Actually, I found a way to find my answer, but it takes 59 lines ... and I need this kind of thing 4 times. S...cadieux_jp (2) From reactions to differential equations 4 49 (11/4/2008 11:20:05 AM) comp.soft-sys.math.mathematicaDear All, from some time now I=E1m working with more and more complex differential equations. Is there a package to transform a set of reaction-kinetic equations such as: { Subscript[a, i] + Subscript...replicatorzed (97)