wolfram-mathematica

问题 I tried this, but failed. fig3D = ContourPlot3D[ x^2 + y^3 - z^2 == 0, {x, -2, 2}, {y, -2, 2}, {z, -2, 2}, PlotPoints -> 100] pts = (InputForm@fig3D)[[1, 1, 1]]; ListSurfacePlot3D[pts] The regenerated surface is very poor. Any suggestions? thanks! 回答1: Not too bad if you specify MaxPlotPoints ListSurfacePlot3D[pts, Mesh -> None, MaxPlotPoints -> 100] Compare with ListSurfacePlot3D[pts] Edit Regarding the export to Excel, please consider that the Excel surface plot is a very basic construction

问题 Is there a built-in Python function such that with vals=[1,2,3,4,5] then foo(vals,2) gives [[1,2],[3,4],[5]] I am looking for the behaviour that Wolfram Language gives with Partition[Range@5, UpTo@2] {{1, 2}, {3, 4}, {5}} 回答1: This is built into neither the Python language itself nor its standard library, but might be what you are looking for functionality-wise: Install the third-party-library more-itertools (not to be confused with the itertools module, which is part of the Python standard

问题 Arising from this question regarding line thickness and point size setting [e.g. PointSize[Large} , PointSize[0.5] ), I was wondering if it is feasible to change PointSize[] , Thickness[] etc in a relative manner? I.e. why is it that PointSize[Larger] doesn't work? Or is possible to somehow query the existing pointsize and perhaps do something like PointSize[1.25*GetPointSize[]] (I haven't been able to figure this out if something like "GetPointSize[]" exists, neither with a quick look at the

问题 How do you obtain graphic primitives and directives from a Graphics object? Leonid Shifrin showed how to remove them in the post Mathematica: Removing graphics primitives. I tried applying something similar but I can't get what I want. Consider this example: g1 = ListPlot3D[ {{0, -1, 0}, {0, 1, 0}, {-1, 0, 1}, {1, 0, 1}, {-1, 1, 1}}, Mesh -> {2, 2}, Boxed -> False, Axes -> False, ViewPoint -> {2, -2, 1}, ViewVertical -> {0, 0, 1}, MeshStyle -> RGBColor[0, 0.5, 0], BoundaryStyle -> RGBColor[1,

问题 In answering this question, I suggested that the OP open a stream at the beginning of his notebook and close it at the end. However, if an Abort is generated, the stream will be left open, and will cause havoc if they attempt to open it again without checking first. If the stream was only required for a single function, the solution would be straightforward, but it's required for the entire notebook. Obviously, a check can be added to see if the stream is already open, but is there a way to

问题 I am trying to dynamically plot data contained in a matrix with Mathematica 7. The data is contained in it like this, obtained via a chemical model. [year H He Li C ... C8H14+,Grain- ] [0 0 0.03 0.009 1E-3 ... 0 ] [100 .1 0.03 0.009 1E-3 ... 0 ] [200 .2 0.03 0.009 1E-3 ... 0 ] [300 .2 0.03 0.009 1E-3 ... 0 ] [... ... ... ... ... ... ... ] [1E6 .5 0.03 0.003 1E-8 ... 1E-25 ] The truth is, the matrix dimensions are 2001*1476 (2000 steps and first line for name, and 1475 compounds + 1 column for

问题 I wish to temporarily rename a built-in symbol and use it with different name while block the main name of this symbol. For example, I wish the following code to print only "2" but not "1" and "3": Block[{print = Print, Print}, Print[1]; print[2]; Print[3];] In really the above code prints nothing. Is it possible to make print working inside such code while completely block symbol Print ? Solutions like With[{Print = f, print = Print}, Print[1]; print[2]; Print[3];] are not suitable since

问题 Good day, When trying to understand the Mathematica 's evaluation sequence by using standard Trace and TraceScan commands and their nice visual representations developed in the recent thread, I faced some ambiguities in their behavior. First of all, when I evaluate In[1]:= Trace[a+1,TraceOriginal->True] I get Out[1]= {a+1,{Plus},{a},{1},a+1,1+a,{Plus},{1},{a},1+a} All sublists correspond to sub-evaluations (as it is stated in the Documentation). The last expression 1+a probably corresponds to

问题 I am attempting to perform a numerical optimisation of a "black box" function in Mathematica. Schematically it goes like this: NMinimize[{comb[x,y,z], x > 0}, {x,y,z}] where comb[x,y,z] is defined similarly to this: comb[x_,y_,z_] := Module[{}, Print[x,y,z]; M = FindMaximum[SkewNormal[a,x,y,z], {a,x}] // First; val = f[x,y,z,M]; Return[val]; ]; However, all of the minimisation functions I have tried seem to not immediately provide comb[x,y,z] with numerical values, and it ends up trying to

问题 I am trying to run a remote mathematica kernel between two macs. Under Kernel Configuration Options For kernel program I have: /Applications/Mathematica.app/Contents/MacOS/MathKernel The arguments of MLOpen: -LinkMode Listen -LinkProtocol TCPIP -LinkOptions MLDontInteract The launch command is: java -jar mathssh username@xxxxxx.dynamic.uiowa.edu /usr/local/bin/math -mathlink -LinkMode Connect -LinkProtocol TCPIP -LinkName " linkname " -LinkHost ipaddress When i use this remote kernel (for