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From: Chris B. <bu...@hv...> - 2002-10-04 21:20:11
|
Hi all. Thanks for the quick reply! To clarify, the script I ran was the standard doublependulum.py that ships with the software. It works fine on my Linux computer (as well as other scripts I've written). I've tried installing VPython on two seperate Macs and get the same behaviour on both. Details: - Mac OSX 10.1.5 - python 2.2.1 installed using fink version 0.4.1 - Installed VPython (Visual-2002-07-22) using the install script Regarding the theta1 suggestion, the script sometimes bombs even before the pendulum completes an oscillation, so I don't think it's a problem with theta becoming too large. It does seem to have something to do with the number of computations, though. I wrote a double-pendulum of my own with Runga-Kutta and it consistently dies more quickly. Unfortunately, I don't maintain the Mac's, I just installed fink to get python working, so I don't know if there might be some esoteric software that might interfere. But fink seems to make its own little world below /sw, so I don't see how there could be a conflict. I also tried installing python from source (ie., not using fink) and I get the same problem. Chris > doublependulum.py is part of the standard VPython demo suite. All the demos > work on other OSX machines. > > Bruce Sherwood > > ----- Original Message ----- > From: "Andy Dougherty" <dou...@la...> > To: "Bruce Sherwood" <bas...@un...> > Cc: "Andy Dougherty" <dou...@ma...>; > <cb...@sw...>; <vis...@li...> > Sent: Friday, October 04, 2002 3:20 PM > Subject: Re: [Visualpython-users] Errors running Vpython on OSX > > > > On Fri, 4 Oct 2002, Bruce Sherwood wrote: > > > > > This vague possibility would seem to be ruled out by the fact that these > > > programs run on other people's Mac OSX machines, with presumably the > same > > > math libraries, no? > > > > Not quite, unless I've misunderstood the original poster's question. > > Yes, Vpython runs fine on other people's Mac OS X machines, but I'm > > unclear if this particular script runs fine on other people's Mac OS X > > machines. > > > > > > > Traceback (most recent call last): > > > > > File "doublependulum.py", line 71, in ? > > > > > atheta2 = -(A*atheta1+C*sin(theta1))/B > > > > > ValueError: unexpected math error > > > > What I'm imagining is that the user is simulating a (possibly damped, > > driven) double pendulum that might have swung over many many times, so > > that theta1 and/or theta2 might be very large compared to 2 pi. That's > > the sort of thing I've seen eventually lead to odd problems elsewhere. > > > > Perhaps if the original script were posted, others could test it. > > > > -- > > Andy Dougherty dou...@la... > > Dept. of Physics > > Lafayette College, Easton PA 18042 > > > > > > |
From: Bruce S. <bas...@un...> - 2002-10-04 20:00:49
|
Many thanks! I should put this on the VPython site. Bruce Sherwood ----- Original Message ----- From: "Kevin Cole" <kj...@gr...> To: <vis...@li...> Sent: Friday, October 04, 2002 3:33 PM Subject: [Visualpython-users] Small note to RH 8.0 users. > > I had VPython working fine on my 7.2 system, but had a few minor > glitches getting it going on the RH 8.0 Beta after returning from the > Tech Circus last weekend. In my case, the fixes (after downloading > the latest and greatest from vpython.org) were: > > 1) Make sure C++ is installed. (As I recall, in 8.0, the package name > changes from "gcc-c++" to "gcc-cpp" but I won't swear to it. You > can check w/ the command "rpm -q gcc-cpp" and/or "rpm -q gcc-c++" > assuming you've installed it using RPM.) > 2) Get the Mandrake Numeric RPM. Pretty current, and it installs no > fuss, no muss. > 3) As the documentation suggests, make sure you know where all your > python stuff lives. Red Hat doesn't put any of it in /usr/local. > So rip "/local" out wherever you see it. (I can't recall, but > I think there was somewhere that I had to remove it that wasn't > mentioned in the documentation. > 4) In my case, I had to change cvisual/CXX/CXX_Config.h, as suggested > by the README.htm in that directory -- though I was a bit surprised, > considering the date mentioned: > > ================================================================ > Version 3 (June 18, 1999) > > 1. CXX compiles with EGCS snapshot 19990616. EGCS requires a > standard library class random_access_iterator that is not > yet available in some other compilers (such as Windows VC6). > Therefore a new switch: > > STANDARD_LIBRARY_HAS_ITERATOR_TRAITS > > has been added to CXX_Config.h that you may need to toggle > if you get an error on the two lines that mention > random_access_iterator. The current definition is correct > for VC6 and EGCS-19990616. > ================================================================ > > Hope this isn't redundant information (or worse yet, incorrect info.) > In any case, it wasn't working til I got all of the above done, and > now it seems fine. > > -- > Kevin Cole, RHCE, Linux Admin | Key ID: 0xE6F332C7 > Gallaudet Research Institute | WWW: http://gri.gallaudet.edu/~kjcole/ > Hall Memorial Bldg S-419 | Voice: (202) 651-5135 > Washington, D.C. 20002-3695 | FAX: (202) 651-5746 > > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > Visualpython-users mailing list > Vis...@li... > https://lists.sourceforge.net/lists/listinfo/visualpython-users > |
From: Bruce S. <bas...@un...> - 2002-10-04 19:57:15
|
doublependulum.py is part of the standard VPython demo suite. All the demos work on other OSX machines. Bruce Sherwood ----- Original Message ----- From: "Andy Dougherty" <dou...@la...> To: "Bruce Sherwood" <bas...@un...> Cc: "Andy Dougherty" <dou...@ma...>; <cb...@sw...>; <vis...@li...> Sent: Friday, October 04, 2002 3:20 PM Subject: Re: [Visualpython-users] Errors running Vpython on OSX > On Fri, 4 Oct 2002, Bruce Sherwood wrote: > > > This vague possibility would seem to be ruled out by the fact that these > > programs run on other people's Mac OSX machines, with presumably the same > > math libraries, no? > > Not quite, unless I've misunderstood the original poster's question. > Yes, Vpython runs fine on other people's Mac OS X machines, but I'm > unclear if this particular script runs fine on other people's Mac OS X > machines. > > > > > Traceback (most recent call last): > > > > File "doublependulum.py", line 71, in ? > > > > atheta2 = -(A*atheta1+C*sin(theta1))/B > > > > ValueError: unexpected math error > > What I'm imagining is that the user is simulating a (possibly damped, > driven) double pendulum that might have swung over many many times, so > that theta1 and/or theta2 might be very large compared to 2 pi. That's > the sort of thing I've seen eventually lead to odd problems elsewhere. > > Perhaps if the original script were posted, others could test it. > > -- > Andy Dougherty dou...@la... > Dept. of Physics > Lafayette College, Easton PA 18042 > > |
From: Kevin C. <kj...@gr...> - 2002-10-04 19:33:56
|
I had VPython working fine on my 7.2 system, but had a few minor glitches getting it going on the RH 8.0 Beta after returning from the Tech Circus last weekend. In my case, the fixes (after downloading the latest and greatest from vpython.org) were: 1) Make sure C++ is installed. (As I recall, in 8.0, the package name changes from "gcc-c++" to "gcc-cpp" but I won't swear to it. You can check w/ the command "rpm -q gcc-cpp" and/or "rpm -q gcc-c++" assuming you've installed it using RPM.) 2) Get the Mandrake Numeric RPM. Pretty current, and it installs no fuss, no muss. 3) As the documentation suggests, make sure you know where all your python stuff lives. Red Hat doesn't put any of it in /usr/local. So rip "/local" out wherever you see it. (I can't recall, but I think there was somewhere that I had to remove it that wasn't mentioned in the documentation. 4) In my case, I had to change cvisual/CXX/CXX_Config.h, as suggested by the README.htm in that directory -- though I was a bit surprised, considering the date mentioned: ================================================================ Version 3 (June 18, 1999) 1. CXX compiles with EGCS snapshot 19990616. EGCS requires a standard library class random_access_iterator that is not yet available in some other compilers (such as Windows VC6). Therefore a new switch: STANDARD_LIBRARY_HAS_ITERATOR_TRAITS has been added to CXX_Config.h that you may need to toggle if you get an error on the two lines that mention random_access_iterator. The current definition is correct for VC6 and EGCS-19990616. ================================================================ Hope this isn't redundant information (or worse yet, incorrect info.) In any case, it wasn't working til I got all of the above done, and now it seems fine. -- Kevin Cole, RHCE, Linux Admin | Key ID: 0xE6F332C7 Gallaudet Research Institute | WWW: http://gri.gallaudet.edu/~kjcole/ Hall Memorial Bldg S-419 | Voice: (202) 651-5135 Washington, D.C. 20002-3695 | FAX: (202) 651-5746 |
From: Andy D. <dou...@la...> - 2002-10-04 19:19:57
|
On Fri, 4 Oct 2002, Bruce Sherwood wrote: > This vague possibility would seem to be ruled out by the fact that these > programs run on other people's Mac OSX machines, with presumably the same > math libraries, no? Not quite, unless I've misunderstood the original poster's question. Yes, Vpython runs fine on other people's Mac OS X machines, but I'm unclear if this particular script runs fine on other people's Mac OS X machines. > > > Traceback (most recent call last): > > > File "doublependulum.py", line 71, in ? > > > atheta2 = -(A*atheta1+C*sin(theta1))/B > > > ValueError: unexpected math error What I'm imagining is that the user is simulating a (possibly damped, driven) double pendulum that might have swung over many many times, so that theta1 and/or theta2 might be very large compared to 2 pi. That's the sort of thing I've seen eventually lead to odd problems elsewhere. Perhaps if the original script were posted, others could test it. -- Andy Dougherty dou...@la... Dept. of Physics Lafayette College, Easton PA 18042 |
From: Bruce S. <bas...@un...> - 2002-10-04 18:45:07
|
This vague possibility would seem to be ruled out by the fact that these programs run on other people's Mac OSX machines, with presumably the same math libraries, no? Bruce Sherwood ----- Original Message ----- From: "Andy Dougherty" <dou...@la...> To: <cb...@sw...> Cc: <vis...@li...> Sent: Friday, October 04, 2002 1:33 PM Subject: Re: [Visualpython-users] Errors running Vpython on OSX > On Fri, 4 Oct 2002, Chris Burns wrote: > > > The problem is that we're on a Mac campus, so I needed to get Vpython > > running on OSX. I followed the instructions and everything seemed fine > > until I ran the demo programs. In any of the demos where there is > > animation (double pendulum, Lorenz, etc), the program bombs at some point > > (not always the same) with a message like: > > > > Traceback (most recent call last): > > File "doublependulum.py", line 71, in ? > > atheta2 = -(A*atheta1+C*sin(theta1))/B > > ValueError: unexpected math error > > One vague possibility: Are you perhaps getting very large theta1 values > here? Although theoretically the trig functions ought to work fine and > automatically take the appropriate mod 2pi, in practice they might not. (I > vaguely recall encountering that problem somewhere in some language, but I > no longer recall the details.) > > -- > Andy Dougherty dou...@la... > Dept. of Physics > Lafayette College, Easton PA 18042 > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > Visualpython-users mailing list > Vis...@li... > https://lists.sourceforge.net/lists/listinfo/visualpython-users > |
From: Andy D. <dou...@la...> - 2002-10-04 17:32:49
|
On Fri, 4 Oct 2002, Chris Burns wrote: > The problem is that we're on a Mac campus, so I needed to get Vpython > running on OSX. I followed the instructions and everything seemed fine > until I ran the demo programs. In any of the demos where there is > animation (double pendulum, Lorenz, etc), the program bombs at some point > (not always the same) with a message like: > > Traceback (most recent call last): > File "doublependulum.py", line 71, in ? > atheta2 = -(A*atheta1+C*sin(theta1))/B > ValueError: unexpected math error One vague possibility: Are you perhaps getting very large theta1 values here? Although theoretically the trig functions ought to work fine and automatically take the appropriate mod 2pi, in practice they might not. (I vaguely recall encountering that problem somewhere in some language, but I no longer recall the details.) -- Andy Dougherty dou...@la... Dept. of Physics Lafayette College, Easton PA 18042 |
From: Bruce S. <bas...@un...> - 2002-10-04 17:20:04
|
This is definitely unknown behavior. Several people (including me) have run all the demos on OSX without seeing these symptoms. If you can, you might try installing on a different Mac to see whether there's something odd with the particular machine you used first. Bruce Sherwood ----- Original Message ----- From: "Chris Burns" <bu...@hv...> To: <vis...@li...> Sent: Friday, October 04, 2002 1:14 PM Subject: [Visualpython-users] Errors running Vpython on OSX > Greetings. > > I've just started using VPython on a linux box and got completely hooked > and started dreaming up all these great demos that would be possible. > The problem is that we're on a Mac campus, so I needed to get Vpython > running on OSX. I followed the instructions and everything seemed fine > until I ran the demo programs. In any of the demos where there is > animation (double pendulum, Lorenz, etc), the program bombs at some point > (not always the same) with a message like: > > Traceback (most recent call last): > File "doublependulum.py", line 71, in ? > atheta2 = -(A*atheta1+C*sin(theta1))/B > ValueError: unexpected math error > > The programs can bomb at different locations (there seems to be no pattern > that I can see). Sometimes, the demo will run for 15-20 seconds before > quitting, sometimes shorter. The real crazy thing is if I put a trace > statement just before the offending line and print out the values to the > screen, it doesn't bomb for a VERY long time (half-hour or so), though it > slows down the animation. It then finally bombs with the following message: > > OverflowError: (35, 'Resource temporarily unavailable') > > Which seems different than the previous one. Needless to say, none of this > happens in Linux, which makes it doubly frustrating, since I know it works, > I just can't show anyone. I haven't had time to really try and debug this, > so I was just wondering if anyone's come accross this and fixed it (I didn't > see any mention in the email archives though). > > Thanks for any help. > > Chris > > -- > Chris Burns > Visiting Assistant Professor > Dept. of physics and astronomy, Swarthmore College > cb...@sw... http://hven.swarthmore.edu/~burns > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > Visualpython-users mailing list > Vis...@li... > https://lists.sourceforge.net/lists/listinfo/visualpython-users > |
From: Chris B. <bu...@hv...> - 2002-10-04 17:14:43
|
Greetings. I've just started using VPython on a linux box and got completely hooked and started dreaming up all these great demos that would be possible. The problem is that we're on a Mac campus, so I needed to get Vpython running on OSX. I followed the instructions and everything seemed fine until I ran the demo programs. In any of the demos where there is animation (double pendulum, Lorenz, etc), the program bombs at some point (not always the same) with a message like: Traceback (most recent call last): File "doublependulum.py", line 71, in ? atheta2 = -(A*atheta1+C*sin(theta1))/B ValueError: unexpected math error The programs can bomb at different locations (there seems to be no pattern that I can see). Sometimes, the demo will run for 15-20 seconds before quitting, sometimes shorter. The real crazy thing is if I put a trace statement just before the offending line and print out the values to the screen, it doesn't bomb for a VERY long time (half-hour or so), though it slows down the animation. It then finally bombs with the following message: OverflowError: (35, 'Resource temporarily unavailable') Which seems different than the previous one. Needless to say, none of this happens in Linux, which makes it doubly frustrating, since I know it works, I just can't show anyone. I haven't had time to really try and debug this, so I was just wondering if anyone's come accross this and fixed it (I didn't see any mention in the email archives though). Thanks for any help. Chris -- Chris Burns Visiting Assistant Professor Dept. of physics and astronomy, Swarthmore College cb...@sw... http://hven.swarthmore.edu/~burns |
From: Bruce S. <bas...@un...> - 2002-10-04 14:52:44
|
Many thanks for this important supplement, Arthur. I should have made this comment, but at the moment I was writing I couldn't remember how to do it! Bruce Sherwood ----- Original Message ----- From: "Arthur" <aj...@ix...> To: "Bruce Sherwood" <bas...@un...>; "vpusers" <vis...@li...> Sent: Friday, October 04, 2002 9:13 AM Subject: Re: [Visualpython-users] Re: strange output > I think it worth supplementing Bruce's analysis with the solution to what > was trying to be accomplished by > > rininitial = ball.pos > > I believe either: > > rinitial = ball.pos[:] > > or > > rinitial =copy(ball.pos) > > would get one to where one is trying to go. > > [:] returns a complete "slice" of the list. > copy, of course, a copy of the list. > > In either case rinitial is no longer an additional name for ball.pos, but an > object independant of it, which will not be modified upon the modification > of ball.pos. > > I think I have this right. Corrections welcome. > > Art |
From: Arthur <aj...@ix...> - 2002-10-04 13:14:57
|
I think it worth supplementing Bruce's analysis with the solution to what was trying to be accomplished by rininitial = ball.pos I believe either: rinitial = ball.pos[:] or rinitial =copy(ball.pos) would get one to where one is trying to go. [:] returns a complete "slice" of the list. copy, of course, a copy of the list. In either case rinitial is no longer an additional name for ball.pos, but an object independant of it, which will not be modified upon the modification of ball.pos. I think I have this right. Corrections welcome. Art ----- Original Message ----- From: "Bruce Sherwood" <bas...@un...> To: "vpusers" <vis...@li...> Sent: Friday, October 04, 2002 8:16 AM Subject: [Visualpython-users] Re: strange output > A VPython user sent me a small program that behaved oddly, and I thought I > should share my analysis, since it involves an aspect of Python that is > subtle and may be missed in early study of the language. Fortunately it > rarely bites students writing computational physics programs! > > Early in the program the user said "rinitial = ball.pos" which means "assign > an additional name to ball.pos, so that in the future one can refer to the > ball's position either by the label (name) ball.pos or the label (name) > rinitial". You can have lots of names pasted onto the same thing. The puzzle > for the user was that later in the program (after moving the ball around), > printing rinitial showed the new value of ball.pos, not the initial value. > > This multiple labeling has consequences only with "mutable" objects such as > lists -- objects whose values can be changed in situ. For example, if you > say "a = 5" and then "b = a", and then say "a = 7", b will still have the > value 5. When you assign 7 to a, you create a new object ("7") and attach > the label "a" to it, so b continues to be a label for the object "5". > > But with "rinitial = ball.pos", you can actually change ball.pos without > creating a new object. For example, you might say "ball.pos.y = 7" in which > case the 2nd element in the ball.pos list has changed (without affecting the > other two elements). Since rinitial is a label for ball.pos, printing > rinitial shows you the new value of ball.pos. > > A list such as [1,2,3] is mutable. The Visual vectors are mutable. A 'tuple' > such as (1,2,3) is not mutable. Constants such as 3 or pi or a string such > as 'cat' are not mutable. > > Needless to say, it took me a while to pay attention to "mutability" as an > important property of Python objects! > > Bruce > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > Visualpython-users mailing list > Vis...@li... > https://lists.sourceforge.net/lists/listinfo/visualpython-users > |
From: Bruce S. <bas...@un...> - 2002-10-04 12:15:22
|
A VPython user sent me a small program that behaved oddly, and I thought I should share my analysis, since it involves an aspect of Python that is subtle and may be missed in early study of the language. Fortunately it rarely bites students writing computational physics programs! Early in the program the user said "rinitial = ball.pos" which means "assign an additional name to ball.pos, so that in the future one can refer to the ball's position either by the label (name) ball.pos or the label (name) rinitial". You can have lots of names pasted onto the same thing. The puzzle for the user was that later in the program (after moving the ball around), printing rinitial showed the new value of ball.pos, not the initial value. This multiple labeling has consequences only with "mutable" objects such as lists -- objects whose values can be changed in situ. For example, if you say "a = 5" and then "b = a", and then say "a = 7", b will still have the value 5. When you assign 7 to a, you create a new object ("7") and attach the label "a" to it, so b continues to be a label for the object "5". But with "rinitial = ball.pos", you can actually change ball.pos without creating a new object. For example, you might say "ball.pos.y = 7" in which case the 2nd element in the ball.pos list has changed (without affecting the other two elements). Since rinitial is a label for ball.pos, printing rinitial shows you the new value of ball.pos. A list such as [1,2,3] is mutable. The Visual vectors are mutable. A 'tuple' such as (1,2,3) is not mutable. Constants such as 3 or pi or a string such as 'cat' are not mutable. Needless to say, it took me a while to pay attention to "mutability" as an important property of Python objects! Bruce |
From: Bruce S. <bas...@un...> - 2002-10-04 12:15:11
|
A VPython user sent me a small program that behaved oddly, and I thought I should share my analysis, since it involves an aspect of Python that is subtle and may be missed in early study of the language. Fortunately it rarely bites students writing computational physics programs! Early in the program the user said "rinitial = ball.pos" which means "assign an additional name to ball.pos, so that in the future one can refer to the ball's position either by the label (name) ball.pos or the label (name) rinitial". You can have lots of names pasted onto the same thing. The puzzle for the user was that later in the program (after moving the ball around), printing rinitial showed the new value of ball.pos, not the initial value. This multiple labeling has consequences only with "mutable" objects such as lists -- objects whose values can be changed in situ. For example, if you say "a = 5" and then "b = a", and then say "a = 7", b will still have the value 5. When you assign 7 to a, you create a new object ("7") and attach the label "a" to it, so b continues to be a label for the object "5". But with "rinitial = ball.pos", you can actually change ball.pos without creating a new object. For example, you might say "ball.pos.y = 7" in which case the 2nd element in the ball.pos list has changed (without affecting the other two elements). Since rinitial is a label for ball.pos, printing rinitial shows you the new value of ball.pos. A list such as [1,2,3] is mutable. The Visual vectors are mutable. A 'tuple' such as (1,2,3) is not mutable. Constants such as 3 or pi or a string such as 'cat' are not mutable. Needless to say, it took me a while to pay attention to "mutability" as an important property of Python objects! Bruce |
From: Bruce S. <bas...@un...> - 2002-10-04 01:49:15
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This is unfamiliar; I routinely exceed such a limit. What platform are you running on? Bruce Sherwood ----- Original Message ----- From: "Charles Tolman" <cha...@ci...> To: <vis...@li...> Cc: <cha...@ci...> Sent: Thursday, October 03, 2002 4:42 AM Subject: [Visualpython-users] 128 point limit in curve? > Hi all, > Newbie here. > > I have just downloaded and run up vpython 2002-07-22 and am now getting a 128 point limit on the curve class. Any more points and it crashes. > When I was running the vpython for python 2.1 (cant remember the vpython number) it definitely did not crash. > > Nice product. Using it for teaching my kids physics. > > TIA > Charles T > > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > Visualpython-users mailing list > Vis...@li... > https://lists.sourceforge.net/lists/listinfo/visualpython-users > |
From: <cha...@ci...> - 2002-10-03 08:42:47
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Hi all, Newbie here. I have just downloaded and run up vpython 2002-07-22 and am now getting a 128 point limit on the curve class. Any more points and it crashes. When I was running the vpython for python 2.1 (cant remember the vpython number) it definitely did not crash. Nice product. Using it for teaching my kids physics. TIA Charles T |
From: Joe H. <hea...@vn...> - 2002-09-26 18:29:05
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Hi. I'm running VPython (07-22-2002 version) under Mac OS X 10.1.5, XFree86 installed via Fink. I have two questions. 1) The program gyro.py in the Demos folder won't give me a graphics window. I get the text window and absolutely no errors whatsoever, just no graphics window. The program gyro2.py works, as do all the other demo programs so far. Program gyro.py runs perfectly under Windows. Any ideas as to what the problem could be? 2) I have no access to the VPython docs under XFree86 because I have no browser installed. Is there one that is preferred over any other? What browser does IDLE look for by default under UNIX (Mac OS X really)? Cheers, Joe Heafner - Instructional Astronomy and Physics Home Page http://users.vnet.net/heafnerj/index.html I don't have a Lexus, but I do have a Mac. Same thing. |
From: Joe H. <hea...@vn...> - 2002-09-22 19:27:02
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Hi. I finally took the plunge and installed VPython on my dual USB iBook running OS 10.1.5 (256MB RAM, 8MB VRAM). I thought I'd share my experience and pose some questions. First, of course, I had to install Fink. That went extremely well using the preprint version of Fun With Fink (<http://www.funwithfink.com>). I also installed Fink Commander, which give a nice Aqua front end to Fink. I then left my iBook overnight to download the ~47MB XFree86 packages and install them. This too went off without a single hitch. I downloaded Window Maker rather than Oroborus and installed it, again with no problems. Regarding Fink, I would like to point out that it is not absolutely necessary to enable the root account under OS X. If the machine is a single user machine, the very first user created at OS X install time has admin privileges, but is not root. The Fun With Fink book points out that when root access is required, one can merely preface the command with "sudo" and then provide the admin (not necessarily root) password and all will still work. This is precisely what I did and it worked perfectly. Installing the rest of the required packages and their dependencies too another several hours of download time (I have dial-up ISP access) but it worked. I have encountered only three problems so far. 1) Under XFree86, how can I get custom icons for my .py Python program files? 2) When I hit "F1" to bring up help, I get an error telling me that no browser can be found. I presume I must install some browser under X so IDLE can find it. Is this correct? 3) The program gyro.py (in /VPython/Programs/Demos/) will not work for me. I get the output window and no errors are shown, but I get no graphics window. So far this is the only program that will not run. Any suggestions? Now I can finally leave MS Windows completely behind! Cheers, Joe Heafner - Instructional Astronomy and Physics Home Page http://users.vnet.net/heafnerj/index.html I don't have a Lexus, but I do have a Mac. Same thing. |
From: Eve K. <e....@sh...> - 2002-09-19 00:29:37
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On Wed, 18 Sep 2002 11:22:58 -0400 (EDT) Andy Dougherty <dou...@la...> wrote: > On Wed, 18 Sep 2002, Eve Kotyk wrote: > > > I did an rpm -q for Mesa-devel-3.4.2.7 and it is installed. > > Hmm. On my Debian/Linux system, glXUseXFont is defined in > /usr/lib/libGL.so, which is provided by mesa. > Running > nm --dynamic /usr/lib/libGL.so | grep glXUseXFont > yields > > 0016b99c T Fake_glXUseXFont > 001687d8 T glXUseXFont You are right I do not have /usr/lib/libGL.so. I do have /usr/lib/libGL.so.1 And the output of nm --dynamic /usr/lib/libGL.so.1 | grep glXUseXFont is: 001acb9c T DRI_glXUseXFont 001582f4 T Fake_glXUseXFont 001558d0 T glXUseXFont Sorry to be so lame, but what can I do about this now? I tried installing OpenGL but it conflicts with my current setup and I recall installing Mesa as a requirement for something else. -- ekotyk |
From: Andy D. <dou...@la...> - 2002-09-18 15:22:02
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On Wed, 18 Sep 2002, Eve Kotyk wrote: > I did an rpm -q for Mesa-devel-3.4.2.7 and it is installed. Hmm. On my Debian/Linux system, glXUseXFont is defined in /usr/lib/libGL.so, which is provided by mesa. Running nm --dynamic /usr/lib/libGL.so | grep glXUseXFont yields 0016b99c T Fake_glXUseXFont 001687d8 T glXUseXFont What do you get? My mesa-dev package identifies itself as mesag-dev version 3.4.2.1-4 (where the -4 is a debian-specific packaging indicator). Hmm. I wonder if for some reason your mesa installation didn't provide /usr/lib/libGL.so ? (Perhaps because the system was reserving that name for a "true" OpenGL library?) -- Andy Dougherty dou...@la... Dept. of Physics Lafayette College, Easton PA 18042 |
From: Eve K. <e....@sh...> - 2002-09-18 12:55:59
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On Wed, 18 Sep 2002 08:31:35 -0400 (EDT) Andy Dougherty <dou...@la...> wrote: > On Tue, 17 Sep 2002, Andrew Morrison wrote: > > > Maybe instead of gtkglarea being the problem, it is a library rpm or > > dev rpm that needs to be installed. > > This sounds quite possible. Libraries often come in either run-time > versions of development versions. The development version is what's > needed to actually compile something, like Vpython. > > Could you look and see if there's a RedHat mesa-dev package (or > something like that) that needs to be installed? I did an rpm -q for Mesa-devel-3.4.2.7 and it is installed. > -- ekotyk |
From: Andy D. <dou...@la...> - 2002-09-18 12:32:11
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On Tue, 17 Sep 2002, Andrew Morrison wrote: > Maybe instead of gtkglarea being the problem, it is a library rpm or > dev rpm that needs to be installed. This sounds quite possible. Libraries often come in either run-time versions of development versions. The development version is what's needed to actually compile something, like Vpython. Could you look and see if there's a RedHat mesa-dev package (or something like that) that needs to be installed? -- Andy Dougherty dou...@la... Dept. of Physics Lafayette College, Easton PA 18042 |
From: Andrew M. <mor...@ph...> - 2002-09-18 02:30:11
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On Tue, 2002-09-17 at 21:16, Bruce Sherwood wrote: > This is very odd, though. Others who have used the VPython installer for > RedHat 7.2 (with gtkglarea-1.2.2-10.i385.rpm) have not reported a problem > with this. >=20 > Bruce Sherwood >=20 The error included in the original message seemed to indicate that somethin= g was trying to use glXUseXFont from libgtkgl.so.5, but was failing. (I don't ac= tually know if I'm right, I'm just guessing.) I couldn't figure out where glXUseX= Font comes from, but I know I have it, because I can bring up the man page. :-) Maybe instead of gtkglarea being the problem, it is a library rpm or dev rp= m that needs to be installed. Just grasping at straws, though...I don't actaully *read* source code. (ha= ha...) Andrew |
From: Bruce S. <bas...@un...> - 2002-09-18 01:47:06
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This is very odd, though. Others who have used the VPython installer for RedHat 7.2 (with gtkglarea-1.2.2-10.i385.rpm) have not reported a problem with this. Bruce Sherwood ----- Original Message ----- From: "Eve Kotyk" <e....@sh...> To: "Andrew Morrison" <mor...@ph...> Cc: <bas...@un...>; <vis...@li...> Sent: Tuesday, September 17, 2002 7:14 PM Subject: Re: [Visualpython-users] libgtkgl.so.5 error On Tue, 17 Sep 2002 11:44:55 -0400 Andrew Morrison <mor...@ph...> wrote: > > Eve... > > What version of gtkglarea do you have? I am using gtkglarea-1.2.1-1, > you probably have something newer. Yes I have what came with VPython which is: /usr/local/bin/VPython/gtkglarea-1.2.2-10.i386.rpm Try downgrading to gtkglarea-1.2.1-1 I'll try it. |
From: Eve K. <e....@sh...> - 2002-09-17 23:14:41
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On Tue, 17 Sep 2002 11:44:55 -0400 Andrew Morrison <mor...@ph...> wrote: > > Eve... > > What version of gtkglarea do you have? I am using gtkglarea-1.2.1-1, > you probably have something newer. Yes I have what came with VPython which is: /usr/local/bin/VPython/gtkglarea-1.2.2-10.i386.rpm Try downgrading to gtkglarea-1.2.1-1 I'll try it. E > and see what happens. (Unless downgrading breaks important > dependencies that you need.) > > Andrew > > On Mon, 2002-09-16 at 22:00, Eve Kotyk wrote: > > On Mon, 16 Sep 2002 15:20:22 -0400 > > Bruce Sherwood <bas...@un...> wrote: > > > > > Presumably this is on Linux? Is there anyone among the VPython > > > users that knows anything about Mesa? I gather it is supposed to > > > be an alternative to OpenGL, but the overview at the Mesa web site > > > implies that one should not expect it to work the same. Since the > > > VPython Visual module interfaces to OpenGL, not Mesa, is there any > > > reason to think that it should work with Mesa? > > > > Redhat Linux v7.2, kernel v 2.4, XFree86 v 4 > > > > Perhaps mentioning that I had Mesa installed is a red herring. > > That aside. How can I solve my problem? > > > > Eve > > > > > > Bruce Sherwood > > > > > > ----- Original Message ----- > > > From: "Eve Kotyk" <e....@sh...> > > > To: <vis...@li...> > > > Sent: Sunday, September 15, 2002 11:17 PM > > > Subject: [Visualpython-users] libgtkgl.so.5 error > > > > > > > > > > I have just installed VPython (and Python2.2) and tried to run > > > > one of the demos. Each one results in the following error. I > > > > have Mesa v3.4.2-7 installed. Can anyone tell me how I can fix > > > > this problem? > > > > > > > > Traceback (innermost last) > > > > File "/usr/local/bin/VPython/Programs/Demos/helix.py", line > > > > 1, in? from visual import * > > > > ImportError: /usr/lib/libgtkgl.so.5: undefined symbol: > > > > glXUseXFont > > > > > > > > -- > > > > > > > > ekotyk > > > > ------------------------------------------------------- > > > > This sf.net email is sponsored by:ThinkGeek > > > > Welcome to geek heaven. > > > > http://thinkgeek.com/sf > > > > _______________________________________________ > > > > Visualpython-users mailing list > > > > Vis...@li... > > > > https://lists.sourceforge.net/lists/listinfo/visualpython-users > > > > > > > > > > > > > -- > > > > ekotyk > > > > http://members.shaw.ca/e.kotyk/virtualstudio.htm > > > > > > ------------------------------------------------------- > > Sponsored by: AMD - Your access to the experts on Hammer Technology! > > Open Source & Linux Developers, register now for the AMD Developer > > Symposium. Code: EX8664 http://www.developwithamd.com/developerlab > > _______________________________________________ > > Visualpython-users mailing list > > Vis...@li... > > https://lists.sourceforge.net/lists/listinfo/visualpython-users > > > > > > -- ekotyk http://members.shaw.ca/e.kotyk/virtualstudio.htm |
From: Andy D. <dou...@la...> - 2002-09-17 16:54:26
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On Mon, 16 Sep 2002, Eve Kotyk wrote: > Redhat Linux v7.2, kernel v 2.4, XFree86 v 4 > > > > I have just installed VPython (and Python2.2) and tried to run one > > > of the demos. Each one results in the following error. I have Mesa > > > v3.4.2-7 installed. Can anyone tell me how I can fix this problem? > > > > > > Traceback (innermost last) > > > File "/usr/local/bin/VPython/Programs/Demos/helix.py", line 1, in > > > ? from visual import * > > > ImportError: /usr/lib/libgtkgl.so.5: undefined symbol: glXUseXFont I don't have a RedHat system, so packaging details could differ, but my libgtkgl.so.5 doesn't have a glXUseXFont symbol anywhere in it. You might have to run nm --dynamic on your various libraries in /usr/lib/*.so to find out who (if anyone) defines that symbol. It may be that you simply need another library added in to the link command. -- Andy Dougherty dou...@la... Dept. of Physics Lafayette College, Easton PA 18042 |