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19h
comment Why Plot3D shows differently with almost the same data
The chat history is here chat.stackexchange.com/transcript/message/27047477#27047477 and I have found the "bug" line which is quite normal, I discussed it here chat.stackexchange.com/transcript/message/27356527#27356527
19h
comment Why Plot3D shows differently with almost the same data
And there is still mysteries in this topic. If you are interested in this, you have another interesting bug to catch : ) Have you read this mathematica.stackexchange.com/q/104382/4742 ? halirutan came up with very clever method to make any librarylink function Listable like Compile function. I successfully tested many librarylink, all works, except this one in the post. The problem is that if I make funcfortran listable, it will get different answers each evaluation.
19h
comment Why Plot3D shows differently with almost the same data
currently, I can only deal with intel compiler in windows and gcc in linux. I wish I could also done this with mingw in windows, in case of that I don't have a intel compiler. But I don't know how to include gfortran lib of mingw in win. I have asked a question, mathematica.stackexchange.com/questions/104668/… the sad thing is, they close it!! They thought this is too specific. So I don't know if you can open the link or not?
19h
comment Why Plot3D shows differently with almost the same data
I am very glad I could show this to you : ) I packed the sample as a zip here 1drv.ms/23MsJt5 The .nb file is written with instruction, hope I make myself clear, if you have any problem, drop me a comment. But I have to say, I haven't completely mastered this technique.
1d
comment Why Plot3D shows differently with almost the same data
I thought as soon as a accept your answer, the 200 will automatically pass to you. I just know that it is not. Anyway, I just click on the bounty button, enjoy : )
Feb
2
comment Why Plot3D shows differently with almost the same data
I got the bug!!! Just like you said, fortran is doing rounding there, it is due to cmplx(w,wdelta) in my fortran code, I should use dcmplx(w,wdelta)! Thank you Jason B. You are an excellent bug hunter! : )
Feb
2
comment Why Plot3D shows differently with almost the same data
Oh, I just notice you've already mentioned in your modified post. w is suspicious, let me check that
Feb
2
comment Why Plot3D shows differently with almost the same data
That is a good idea, and I have confirmed my native fortran code already have this problem. What is more, even I remove the if branch in my code, it also produce the steps!! Damn! What on earth are they? Do you have any clever guesses? : )
Feb
1
comment Why Plot3D shows differently with almost the same data
But definitely a +1 first : )
Feb
1
comment Why Plot3D shows differently with almost the same data
I really appreciate your help : ) I just checked my fortran source several time again, still finding nothing. I will check further, for they are actually not exactly the same, though I personally believe that should not matter that much. Now I am not quite sure whether it is a problem of my source or a problem of mixing C process, or a problem of librarlylink. So I am not that optimistic, maybe I need another person to shed some light on my fortran and C source too : )
Feb
1
comment Why Plot3D shows differently with almost the same data
That is convincing finding. The two functions are so similar, I thought they should be the same, problem maybe due to plot3d. While it turn out that they are "drastically" different now. I have to recheck my fortran source.
Feb
1
comment Why Plot3D shows differently with almost the same data
@SquareOne No difference : )
Feb
1
comment Why Plot3D shows differently with almost the same data
@SquareOne Sorry for the confusion. The parameter of funcfortran is all real, while the w in funcom is complex. But it is just a sight difference in definition. I should had made it real also. But anyway, I just tried a modified real version of funcom, the result is the same
Feb
1
comment Why Plot3D shows differently with almost the same data
Wow, finally someone gives an answer. Thank you Jason B for spending your time helping me. I am looking into your answer right now. Reap and Sow is showing something, but I think you maybe overlooked those dark stripes in the 3rd plot, they exactly corresponding those defective part of 2nd plot. But on these dark strips, there is no value difference, they are flat. I think this should be the key problem instead of those 10-6 differences, what do you think?
Jan
29
comment Playing a sound gives errors in Mathematica 10.3
@OleksandrR. So I can expect this post to be reopened now : )
Jan
29
comment Playing a sound gives errors in Mathematica 10.3
@m_goldberg Sorry for late reply. I found the cause and updated my post.
Jan
20
comment How to convert Graphics3D object into an Image3D object?
@R.M. Because we can use Manipulate to inspect a 3D object slice by slice?
Jan
20
comment How to rasterize a Graphics3D expression into an Image3D?
But if you want generate image3d from such as DensityPlot3D, this can be done by calculating the data on a regular mesh first, and using Image3D[data] to generate 3d object
Jan
20
comment Is it possible for librarylink function to be Listable like that in Compile?
Evaluated->False is undocumented??!!
Jan
20
comment How to rasterize a Graphics3D expression into an Image3D?
5 months passed, there is still no solution to this? Unbelievable. I think your question is very useful, it is not getting enough attention.