cosmicstring

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18 years, 230 days

MaplePrimes Activity


These are replies submitted by cosmicstring

@Preben Alsholm 

Thank your very much for the detailed reply. I changed my settings to 1D input (and 1D output to be sure) and inserted the split just as you did. And it worked! Back to old days for solution!

Edit:

Now I tried in the 2D Input&Output mode but

plotsetup(ps, plotoutput = `myplot.eps`, plotoptions = `portrait,noborder`):
display(rplot)

lines in another execution group. Then it worked again.

@Preben Alsholm 

Thank your very much for the detailed reply. I changed my settings to 1D input (and 1D output to be sure) and inserted the split just as you did. And it worked! Back to old days for solution!

Edit:

Now I tried in the 2D Input&Output mode but

plotsetup(ps, plotoutput = `myplot.eps`, plotoptions = `portrait,noborder`):
display(rplot)

lines in another execution group. Then it worked again.

@Preben Alsholm 

Thank you for your comment. So you have a file named myplot.eps in your harddisc? I cannot generate it. Viewing is not a problem. After your comment I tried with a semicolon, too.

I am using the fancy worksheet (not the classic one) and Windows 7. Can it be the origin of my problem?

@Joe Riel Thank you Joe! Now it works!

@Joe Riel Thank you Joe! Now it works!

Thank you very much Joe!

This work-around lets me see the numerical values. Then, I tried to plot my solution using odeplot.

First I tried the most basic form:

Then,

to plot just R1(r). To plot the real part of R1(r), I tried:

But none of them plotted the results. I checked some numerical values and there should be some graphs:

   [r = 2., R1(r) = 0.110429803108025 - 0.115236213462622 I,

     R2(r) = 0.128139507027451 + 0.0432522993325482 I]
  [r = 2.1, R1(r) = 0.115352112959516 - 0.127490328044104 I,

    R2(r) = 0.116860522168709 + 0.0553980382159244 I]
  [r = 2.2, R1(r) = 0.121548358755804 - 0.138589827223535 I,

    R2(r) = 0.105026606192974 + 0.0687118967487442 I]
  [r = 2.3, R1(r) = 0.129129499693604 - 0.148472718421773 I,

    R2(r) = 0.0925046702134434 + 0.0830754749112501 I]
  [r = 2.4, R1(r) = 0.138194280312590 - 0.157063052476409 I,

 etc.

Is it possible that this bug prevents odeplot to reach the soltn to get the numerical values? (I am using odeplot for the first time, so I may be missing a point.)

Thank you very much Joe!

This work-around lets me see the numerical values. Then, I tried to plot my solution using odeplot.

First I tried the most basic form:

Then,

to plot just R1(r). To plot the real part of R1(r), I tried:

But none of them plotted the results. I checked some numerical values and there should be some graphs:

   [r = 2., R1(r) = 0.110429803108025 - 0.115236213462622 I,

     R2(r) = 0.128139507027451 + 0.0432522993325482 I]
  [r = 2.1, R1(r) = 0.115352112959516 - 0.127490328044104 I,

    R2(r) = 0.116860522168709 + 0.0553980382159244 I]
  [r = 2.2, R1(r) = 0.121548358755804 - 0.138589827223535 I,

    R2(r) = 0.105026606192974 + 0.0687118967487442 I]
  [r = 2.3, R1(r) = 0.129129499693604 - 0.148472718421773 I,

    R2(r) = 0.0925046702134434 + 0.0830754749112501 I]
  [r = 2.4, R1(r) = 0.138194280312590 - 0.157063052476409 I,

 etc.

Is it possible that this bug prevents odeplot to reach the soltn to get the numerical values? (I am using odeplot for the first time, so I may be missing a point.)

@Torre 

I am not using any assumptions and symbolic simplifications. I understand that it is not easy (even impossible) to guess the error without seeing the problem itself if there is not a well-known issue.

Thank you very much for your kind consideration. I will go on trying with some other known metrics and write here again if I experience the same problem.

By the way, I can find some other Killing vectors by hand and take the Lie derivative using Maple and find zero as it should be.

@Torre 

I am not using any assumptions and symbolic simplifications. I understand that it is not easy (even impossible) to guess the error without seeing the problem itself if there is not a well-known issue.

Thank you very much for your kind consideration. I will go on trying with some other known metrics and write here again if I experience the same problem.

By the way, I can find some other Killing vectors by hand and take the Lie derivative using Maple and find zero as it should be.

I was following the help page,

http://www.maplesoft.com/support/help/Maple/view.aspx?path=DifferentialGeometry%2FTensor%2FKillingVectors

and use the "map" command to see the situation for the whole set of the Killing vectors. After your comment, I tried without the "map" and got the same nonzero results.

I simplify by hand in many cases but in this case there is for example a term with "dt &t dphi" with a nonzero coefficient.

I was following the help page,

http://www.maplesoft.com/support/help/Maple/view.aspx?path=DifferentialGeometry%2FTensor%2FKillingVectors

and use the "map" command to see the situation for the whole set of the Killing vectors. After your comment, I tried without the "map" and got the same nonzero results.

I simplify by hand in many cases but in this case there is for example a term with "dt &t dphi" with a nonzero coefficient.

but I prefer not to write the metric as it is not published yet. Can you think of any possible issues?

Thanks Charlie! I am using Maple 16. My metric is not very complicated but I am not authorized to write it here. I wonder if there are known issues on that command or a possible special parametrization.

Thank you, this worked for me and I added my solution for playing sounds in Win7 to the post you recommended.

Thank you, this worked for me and I added my solution for playing sounds in Win7 to the post you recommended.

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