Nasser

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bio	website	12000.org
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	7,645 reputation	bio	website	12000.org	visits	member for	1 year, 4 months
1031 badges		location	the great state of Wisconsin		seen	Mar 12 at 19:57

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Mar 8	comment	Go to definition of symbol/variable .. I'll be happy with just having good old fashioned source line numbers in the notebook myself. May be in version 16 of Mathematica we will get this feature finally added. It must be very hard to do.
Mar 8	comment	Go to definition of symbol/variable try `?name` and `??name` This will just display the information about the name/symbol. I do not know of a way to actually jump to where the symbol is first seen in a notebook. There are ways to tag cells, and then use the tag as marker. But I am sure this is not what you wanted here.
Mar 8	comment	Mathematica vs. $\LaTeX$? Replacement for Legacy “Authoring Tools” package? You said: `The Mathematica Guidebook, which appears to have been written entirely in MMA with Authoring tools` This is not exactly the way I read it. Here is description from the book itself. Tex was used for production. !Mathematica graphics I do not see any mention of `Authoring tools` in this description.
Mar 8	comment	Inconsistent results from equivalent integrals if I did not know any better, I'd say this a bug. `Integrate[1/TrigToExp[a^2Cos[t]^2 + b^2Sin[t]^2], {t, 0, 2*Pi}]` gives zero. !Mathematica graphics So clearly changing the form should not have made a difference in result.
Mar 8	comment	Does pass-by-value affect the performance of function calls? I actually still do not see how it does not affect performance. When I pass a list of 1 GB to a function, and that function wants to modify one entry in this list, then a copy of the whole list needs to be made and the copy is modified and returned. So how is Mathematica able to copy a 1 GB (and also freeing the old list) without any performance penalty? I mean compared to pass by reference, where no copying is needed. There should be performance difference. Did malloc() and free() become so fast these days? Example !Mathematica graphics
Mar 8	comment	Plotting with Units Do you think mixing Wolfram alpha input (I assume this is what you call natural language input) within Mathematica code is a good idea? Can you run this code again when the internet is down? Why not write everything using normal Mathematica code? I never thought the idea of mixing so called natural language input within Mathematica is a good idea. Just adds more confusion for little added benefit.
Mar 8	comment	Does pass-by-value affect the performance of function calls? @LeonidShifrin Yes, you are right. I do not use `Unevaluated[]` any more.
Mar 8	comment	Does pass-by-value affect the performance of function calls? also this question stackoverflow.com/questions/7376032/… I see no difference in this simple test !Mathematica graphics
Mar 6	comment	Draw only the top of the boundary of a function in Plot3d hard to say with seeing the code, but may be `RegionPlot3D` can be used? for 2D there is `RegionPlot`.
Mar 6	comment	2D Heat equation: inconsistent boundary and initial conditions @DanielLichtblau. yes. Please see this page 12000.org/my_courses/UC_davis/fall_2010/math_228a/HWs/HW3 I used M for this course (it was a graduate course in numerical PDE's at UC Davis). On the above page you'll see the PDF file of this document a little down the page.
Mar 6	comment	2D Heat equation: inconsistent boundary and initial conditions btw, doing Neumann B.C. can be tricky in finite difference. I spend sometime to write a note on this since I kept making mistakes in it. Here is the note, it shows how to discretize 2D for Neumann on the different edges. This is only useful for someone doing FDM by hand ofcourse, not using NDSolve : 12000.org/my_courses/UC_davis/fall_2010/math_228a/HWs/HW3/…
Mar 6	comment	How can I control Dynamic property? @halirutan I assumed when I saw the code that the tab setting in Subbu notebook was misconfigured somehow of he might have changed the setting there to his preference as I never seen M generate such large spaces before. I agree, it makes the code harder to read and understand.
Mar 6	comment	How can I control Dynamic property? hi; is is possible to make a smaller example that illustrate the problem? Actually, many times I find myself, when I want to ask a question, I go to make a small example to show the problem, and when making this small example, I end up finding my problem, because I eliminated many things that made it hard to see the problem, or by just making the small example to reproduce it, it helped me learn what the problem was. May be you can try that?
Mar 6	comment	2D Heat equation: inconsistent boundary and initial conditions +1 good find! But this makes one wonder if M error message in this case could have been made more helpful to users. Since M knows the B.C. is Neumann, and so internally it must have gone through this code path. Then why not make a more informative error message in this case? This would have saved the user much time. WHat I mean, it says `This happens due to discretization error in approximating Neumann boundary conditions` So, M knows the error! then why not issue this error instead of one given?
Mar 6	comment	Plotting Energies vs. m for all values of R with the colors of the levels indexed by R So it looks like you 2 degrees of freedom then. R and m are the independent variables, and the dependent variable is the energy. So your energy(R,m) is a function. So you need 3D plot. The x-axis will be R and the y-axis will be m, and the z-axis is energy(R,m). There are many ways to make 3D plots in M depending on how you want to visualize the result.
Mar 6	comment	PlotLegends in ListContourPlot for triplet of data showing strange numbers Since you are on Linux and we both have same version of M (9.0.1) then it must be a bug in the linux version, as I do not see it on windows. But lets wait for others to see.
Mar 6	comment	Copy and pasted graphics are fuzzy @Szabolcs I found that if I simply take screen shot, then use PAINT.EXE to grap the screen shot image, then save that to .png, then use the .png in my Latex document, I get the best picture. Strange that if I select the cell in M, then do FILE->SAVE SELECTION AS->PNG, I get bad quality .png comparse to just doing screen shot. I am on windows 7, using M V 9.01 This happens all the time, regardless of the plot I am trying to export from M to Latex.
Mar 6	comment	PlotLegends in ListContourPlot for triplet of data showing strange numbers fyi, these side numbers do NOT show up in V 9.01. Screen shot: !Mathematica graphics I am on windows 7
Mar 6	comment	Collecting roots of different equations and create a list Yes, you need to use Flatten if you have lists of solutions in there. I did not show Flatten for FindRoots examples, but did for Solve examples.
Mar 6	comment	Collecting roots of different equations and create a list I just picked one point to find root near, which is one. This was to make up some example. I do not know what is your code doing. May be you can post your code in your question, making sure it runs clean. Then one can use your code to show the steps. i.e. just post the equations and the `FindRoot` command used. What you posted before does not run. Need to post complete self contained code.