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From: Tony Vignaux <Tony.V<ignaux@mc...>  20051014 19:27:19

There is a group of unit tests included in the SimPy directory of the distribution. The main one is testSimpy.py. On Oct 15, 2005, at 2:31 AM, Stan Pinte wrote: > Is there a regression test suite for Simpy, to get a good level of > confidence it works? > > I would like to try it on IronPython 0.9.3... > > (I currently use it on PythonDotNet, and it rocks! thanks to all!) > > Stan. Tony Vignaux vignaux@... 
From: Stan Pinte <stan@ph...>  20051014 13:32:18

hello, Is there a regression test suite for Simpy, to get a good level of confidence it works? I would like to try it on IronPython 0.9.3... (I currently use it on PythonDotNet, and it rocks! thanks to all!) Stan. 
From: John Pennington Metta <penningj@en...>  20051012 17:01:37

I've moved this discussion to the Pyarie list since it is mainly=20 specific to Pyarie and continuous modeling. Feel free to join at pyarieusers@... Cheers j Nicolas Pernetty wrote: > Hi John, >=20 > I've had a long loog at Pyarie and SimPy. > Good news is that I've understood almost everything (thanks to the > Python clear syntax and to the comments !) and that I had no problem > running your example (even managed to create new ones). >=20 > I think that I can build upon your work without too much difficulties. > I need some more time to digest everything and to clear my head before > giving you a full review, but something that I haven't quite grasped is > how can we manage multiple models/process ? >=20 > For instance, let's say we have a closed system : A and B have effects > on C and C has effects on B. > In a procedural language, I'll do the loop like this : >=20 > 10: > computeA(stateA, outA) > computeB(stateB, outC, outB) > computeC(stateC, outA, outB, outC) > goto 10 >=20 > In reality we can have a much more complex tree, so do we have to > somehow design a solver which deduce the tree call from the information= s > or do we have to input the tree as well ? I think that somehow it is > already solved in SimPy... >=20 > As for my line of work, I'm involved in multiple mechanical bodies > simulation. For instance I can model an airplane, with the engine, the > wings, gravity and atmosphere as well as an autopilot. >=20 > Ok, give me at least 12 weeks to play and tweak with Pyarie/SimPy > before fully understand what I can do with it. >=20 > Thanks again for your help, >=20 > P.S. : sorry for my poor english, but it's really late and I'm really > tired... ;) >=20 > *********** REPLY SEPARATOR *********** >=20 > On Mon, 10 Oct 2005 16:25:49 0700, John Pennington Metta > <penningj@...> wrote : >=20 >=20 >>Nicolas, >> >>Multiple solution routines should be trivial in Pyarie. It's based on=20 >>the simultaneous (with respect to timestep) solution of a system of=20 >>equations. Each system (e.g. a nitrogen cycling model) is built as a=20 >>class, with member functions for each equation (i.e. organic nitrogen) >> >>or subroutine within an equation. >> >>The system doesn't care how the equation is solved. In other words, it >> >>matters not whether you use mathematics or define a routine to look up >> >>values in a table. You could even define the function in such a way >>that it looks up a value and if the value can't be found in the >>table, then calculates it and adds the calculated value to a table >>for later use. >> >>This all, of course, assumes that you are using the system in such a >>way that each state variable is defined by a function. I'd be >>interested in learning more about what you're doing and what you >>need. As the documentation states, I designed this for my use in >>river ecosystem modeling, but I'd like it to be as generally usable >>as possible. >> >>Cheers, >>J >> >> >>Nicolas Pernetty wrote: >> >>>Hi John, >>> >>>Thank you for your answer. I've just downloaded the package and will >>>have a look on it next week. >>> >>>About continuous system modeling, I'm personnaly involved in >>>mechanics system simulator (23 body linked together) and found it >>>extremely difficult to design the basic sets of equation without >>>approximations. Results are often hugely complex and slow. >>> >>>We have tried to use readily available generic simulator (like >>>SimMechanics) but without success. >>> >>>We decided to assume approximation, and thus managed to dramatically >>>simplify the set of equations, which we implemented 'by hand' in C. >>>Problem is that such approach has to be unique and repeated each >>>time someone has to design a simulator (because approximations are >>>different). >>> >>>Another constraint I have is that some parts of the simulator has to >>>be run by data files. Indeed some parts are so difficult that it is >>>useless to try to represent it by equations. So some other people >>>use different method (like finite elements computation) and give me >>>the result in the form of data files. For instance for an airplane, >>>I can have time vs mass vs flow in the data file. >>> >>>So my simulator is composed of equations, data files and some >>>solver. How can I design a generic program capable of handling every >>>situations is my current problem ! ;) >>> >>>I would be happy to build on your project (if possible) and made it >>>available to the Python community... >>> >>>I'll keep you informed of my progress, >>> >>>Thank you again, >>> >>>*********** REPLY SEPARATOR *********** >>> >>>On Fri, 07 Oct 2005 08:07:34 0700, John Pennington Metta >>><penningj@...> wrote : >>> >>> >>> >>>>Nicolas, >>>>I'm working on Pyarie (pyarie.wikisophia.org), a system designed=20 >>>>(theoretically) to take an arbitrary set of equations and solve >>> >>>them, >tracking system or state variables, using a variety of >>>solution >methods (RungeKutta, etc). >>> >>>>It's functional right now, but needs a great deal of cleaning up and >>>>has a lot of gaps (probability distributions, etc.). I was >>> >>>originally > >>> >>>>writing it for some modeling I'm doing for my thesis, but we took a=20 >>>>different path, so it's on a bit of a hold. >>>> >>>>There is one version that would probably be fine for you and which=20 >>>>works. It just requires the user to build his/her equations and=20 >>>>variables (along with timestep, output timestep, initial conditions, >>> >>>>etc) into two modules. After which the model will run, and spit all >>>>the state variables at each output timestep to a text file which >>> >>>you >could graph (I linked it successfully with gnuplot at one >>>point, and >it ran and output graphs transparently). >>> >>>>The link with SimPy is that continuous modeling is essentially >>>>discrete, in that we have to solve most equations at each timestep. >>>>So SimPy is the backend to the software, controlling the solution >>> >>>to >the equation as a discrete processes at the given timestep. >>> >>>>For a nonprogrammer, the current prealpha version is >>> >>>nonfunctional, > >>> >>>>but for you it would work fine (the programming you have to do is=20 >>>>essentially just entering your equations correctly). Please feel >>> >>>free >to email me if there are any questions (which there will be), >>>but I >think there's still a sample model included (testmodel.py >>>holds the >equations, testsimulation sets up the initial variables, >>>solver, >timestep, etc.) >>> >>>>Also, let me know what you'd like to, or do, change. I'm always=20 >>>>interested in making this better for others. Eventually I'll clean >>> >>>it >up and publish it. >>> >>>>Cheers, >>>>J >>>> >>>>p.s. I just noticed that some fiends completely erased every page of >>>>the wikibased home, so I'll have to modify that so noone can edit >>>>it, and replace all the information. >>>> >>>> >>>>Klaus Muller wrote: >>>> >>>> >>>>>Hi Nicolas! >>>>>There has been some work on continuous system simulation in Python: >>>>> >>>>>1) traffic simulation (using SimPy, too): >>>>>http://bitsko.slc.ut.us/blog/prtlrtsim.html >>>>>2) a paper presented at EuroPython 2005: >>>>>http://www.pythoninbusiness.org/ep2005/talk.chtml?talk=3D2273&trac >>> >>>k=3D646 >>3) an excellent book: "Python Scripting for Computational >>>Science" >>by H. P. Langtangen (Springer) >>> >>>>>If you find out moe, please, let us all know. We may yet be able to >>>>>make SimPy a hybrid simulation package. >>>>> >>>>>Klaus M=FCller >>>>> >>>>> >>>>> >>>>> >>>>> >>>>>>Original Message >>>>>>From: simpyusersadmin@...=20 >>>>>>[mailto:simpyusersadmin@...] On Behalf Of=20 >>>>>>Nicolas Pernetty >>>>>>Sent: Friday, October 07, 2005 1:16 AM >>>>>>To: simpyusers@... >>>>>>Subject: [Simpyusers] Continuous system simulation in Python >>>>>> >>>>>>Hello, >>>>>> >>>>>>I'm looking for any work/paper/ressource about continuous=20 >>>>>>system simulation using Python or any similar object oriented=20 >>>>>>languages (or even UML theory !). >>>>>> >>>>>>I'm aware that SimPy is for discrete event simulation, but=20 >>>>>>maybe you would have heard of any similr work on continuous=20 >>>>>>system. I would like to develop a generic continous system=20 >>>>>>simulator, and so would be eager to join any open source=20 >>>>>>effort on the subject. >>>>>> >>>>>>For instance, it would be useful for modelling an airplane=20 >>>>>>with all the dynamics (flight simulator). >>>>>> >>>>>>Python is my language of choice because of the keyword=20 >>>>>>'generic'. Being an object oriented dynamic language, it's=20 >>>>>>perfect for such a task. >>>>>>Unfortunately I'm a novice when it comes to object oriented=20 >>>>>>design and development, so I would prefer to start from=20 >>>>>>something already existent instead of starting from scratch. >>>>>> >>>>>>If you had any idea on the subject, I would be really glad to=20 >>>>>>discuss it with you. >>>>>> >>>>>>Thanks in advance, >>>>>> >>>>>> >>>>>> >>>>>>This SF.Net email is sponsored by: >>>>>>Power Architecture Resource Center: Free content, downloads,=20 >>>>>>discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl >>>>>>_______________________________________________ >>>>>>Simpyusers mailing list >>>>>>Simpyusers@... >>>>>>https://lists.sourceforge.net/lists/listinfo/simpyusers >>>>>> >>>> >=20 >=20 >  > This SF.Net email is sponsored by: > Power Architecture Resource Center: Free content, downloads, discussion= s, > and more. http://solutions.newsforge.com/ibmarch.tmpl > _______________________________________________ > Simpyusers mailing list > Simpyusers@... > https://lists.sourceforge.net/lists/listinfo/simpyusers =20 John Metta (yes, my name has indeed changed...) http://oregonstate.edu/~penningj/ "A computer without windows is like a dog without bricks tied to its head." 
From: Nicolas Pernetty <nicopernetty@ya...>  20051012 01:13:29

Hi John, I've had a long loog at Pyarie and SimPy. Good news is that I've understood almost everything (thanks to the Python clear syntax and to the comments !) and that I had no problem running your example (even managed to create new ones). I think that I can build upon your work without too much difficulties. I need some more time to digest everything and to clear my head before giving you a full review, but something that I haven't quite grasped is how can we manage multiple models/process ? For instance, let's say we have a closed system : A and B have effects on C and C has effects on B. In a procedural language, I'll do the loop like this : 10: computeA(stateA, outA) computeB(stateB, outC, outB) computeC(stateC, outA, outB, outC) goto 10 In reality we can have a much more complex tree, so do we have to somehow design a solver which deduce the tree call from the informations or do we have to input the tree as well ? I think that somehow it is already solved in SimPy... As for my line of work, I'm involved in multiple mechanical bodies simulation. For instance I can model an airplane, with the engine, the wings, gravity and atmosphere as well as an autopilot. Ok, give me at least 12 weeks to play and tweak with Pyarie/SimPy before fully understand what I can do with it. Thanks again for your help, P.S. : sorry for my poor english, but it's really late and I'm really tired... ;) *********** REPLY SEPARATOR *********** On Mon, 10 Oct 2005 16:25:49 0700, John Pennington Metta <penningj@...> wrote : > Nicolas, > > Multiple solution routines should be trivial in Pyarie. It's based on > the simultaneous (with respect to timestep) solution of a system of > equations. Each system (e.g. a nitrogen cycling model) is built as a > class, with member functions for each equation (i.e. organic nitrogen) > > or subroutine within an equation. > > The system doesn't care how the equation is solved. In other words, it > > matters not whether you use mathematics or define a routine to look up > > values in a table. You could even define the function in such a way > that it looks up a value and if the value can't be found in the > table, then calculates it and adds the calculated value to a table > for later use. > > This all, of course, assumes that you are using the system in such a > way that each state variable is defined by a function. I'd be > interested in learning more about what you're doing and what you > need. As the documentation states, I designed this for my use in > river ecosystem modeling, but I'd like it to be as generally usable > as possible. > > Cheers, > J > > > Nicolas Pernetty wrote: > > Hi John, > > > > Thank you for your answer. I've just downloaded the package and will > > have a look on it next week. > > > > About continuous system modeling, I'm personnaly involved in > > mechanics system simulator (23 body linked together) and found it > > extremely difficult to design the basic sets of equation without > > approximations. Results are often hugely complex and slow. > > > > We have tried to use readily available generic simulator (like > > SimMechanics) but without success. > > > > We decided to assume approximation, and thus managed to dramatically > > simplify the set of equations, which we implemented 'by hand' in C. > > Problem is that such approach has to be unique and repeated each > > time someone has to design a simulator (because approximations are > > different). > > > > Another constraint I have is that some parts of the simulator has to > > be run by data files. Indeed some parts are so difficult that it is > > useless to try to represent it by equations. So some other people > > use different method (like finite elements computation) and give me > > the result in the form of data files. For instance for an airplane, > > I can have time vs mass vs flow in the data file. > > > > So my simulator is composed of equations, data files and some > > solver. How can I design a generic program capable of handling every > > situations is my current problem ! ;) > > > > I would be happy to build on your project (if possible) and made it > > available to the Python community... > > > > I'll keep you informed of my progress, > > > > Thank you again, > > > > *********** REPLY SEPARATOR *********** > > > > On Fri, 07 Oct 2005 08:07:34 0700, John Pennington Metta > > <penningj@...> wrote : > > > > > >>Nicolas, > >>I'm working on Pyarie (pyarie.wikisophia.org), a system designed > >>(theoretically) to take an arbitrary set of equations and solve > >them, >tracking system or state variables, using a variety of > >solution >methods (RungeKutta, etc). > >> > >>It's functional right now, but needs a great deal of cleaning up and > >>has a lot of gaps (probability distributions, etc.). I was > >originally > > >>writing it for some modeling I'm doing for my thesis, but we took a > >>different path, so it's on a bit of a hold. > >> > >>There is one version that would probably be fine for you and which > >>works. It just requires the user to build his/her equations and > >>variables (along with timestep, output timestep, initial conditions, > > > >>etc) into two modules. After which the model will run, and spit all > >>the state variables at each output timestep to a text file which > >you >could graph (I linked it successfully with gnuplot at one > >point, and >it ran and output graphs transparently). > >> > >>The link with SimPy is that continuous modeling is essentially > >>discrete, in that we have to solve most equations at each timestep. > >>So SimPy is the backend to the software, controlling the solution > >to >the equation as a discrete processes at the given timestep. > >> > >>For a nonprogrammer, the current prealpha version is > >nonfunctional, > > >>but for you it would work fine (the programming you have to do is > >>essentially just entering your equations correctly). Please feel > >free >to email me if there are any questions (which there will be), > >but I >think there's still a sample model included (testmodel.py > >holds the >equations, testsimulation sets up the initial variables, > >solver, >timestep, etc.) > >> > >>Also, let me know what you'd like to, or do, change. I'm always > >>interested in making this better for others. Eventually I'll clean > >it >up and publish it. > >> > >>Cheers, > >>J > >> > >>p.s. I just noticed that some fiends completely erased every page of > >>the wikibased home, so I'll have to modify that so noone can edit > >>it, and replace all the information. > >> > >> > >>Klaus Muller wrote: > >> > >>>Hi Nicolas! > >>>There has been some work on continuous system simulation in Python: > >>> > >>>1) traffic simulation (using SimPy, too): > >>>http://bitsko.slc.ut.us/blog/prtlrtsim.html > >>>2) a paper presented at EuroPython 2005: > >>>http://www.pythoninbusiness.org/ep2005/talk.chtml?talk=2273&trac > >k=646 >>3) an excellent book: "Python Scripting for Computational > >Science" >>by H. P. Langtangen (Springer) > >>> > >>>If you find out moe, please, let us all know. We may yet be able to > >>>make SimPy a hybrid simulation package. > >>> > >>>Klaus Müller > >>> > >>> > >>> > >>> > >>>>Original Message > >>>>From: simpyusersadmin@... > >>>>[mailto:simpyusersadmin@...] On Behalf Of > >>>>Nicolas Pernetty > >>>>Sent: Friday, October 07, 2005 1:16 AM > >>>>To: simpyusers@... > >>>>Subject: [Simpyusers] Continuous system simulation in Python > >>>> > >>>>Hello, > >>>> > >>>>I'm looking for any work/paper/ressource about continuous > >>>>system simulation using Python or any similar object oriented > >>>>languages (or even UML theory !). > >>>> > >>>>I'm aware that SimPy is for discrete event simulation, but > >>>>maybe you would have heard of any similr work on continuous > >>>>system. I would like to develop a generic continous system > >>>>simulator, and so would be eager to join any open source > >>>>effort on the subject. > >>>> > >>>>For instance, it would be useful for modelling an airplane > >>>>with all the dynamics (flight simulator). > >>>> > >>>>Python is my language of choice because of the keyword > >>>>'generic'. Being an object oriented dynamic language, it's > >>>>perfect for such a task. > >>>>Unfortunately I'm a novice when it comes to object oriented > >>>>design and development, so I would prefer to start from > >>>>something already existent instead of starting from scratch. > >>>> > >>>>If you had any idea on the subject, I would be really glad to > >>>>discuss it with you. > >>>> > >>>>Thanks in advance, > >>>> > >>>> > >>>> > >>>>This SF.Net email is sponsored by: > >>>>Power Architecture Resource Center: Free content, downloads, > >>>>discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl > >>>>_______________________________________________ > >>>>Simpyusers mailing list > >>>>Simpyusers@... > >>>>https://lists.sourceforge.net/lists/listinfo/simpyusers > >>>> > >> > 
From: John Pennington Metta <penningj@en...>  20051010 23:25:43

Nicolas, Multiple solution routines should be trivial in Pyarie. It's based on=20 the simultaneous (with respect to timestep) solution of a system of=20 equations. Each system (e.g. a nitrogen cycling model) is built as a=20 class, with member functions for each equation (i.e. organic nitrogen)=20 or subroutine within an equation. The system doesn't care how the equation is solved. In other words, it=20 matters not whether you use mathematics or define a routine to look up=20 values in a table. You could even define the function in such a way that=20 it looks up a value and if the value can't be found in the table, then=20 calculates it and adds the calculated value to a table for later use. This all, of course, assumes that you are using the system in such a way=20 that each state variable is defined by a function. I'd be interested in=20 learning more about what you're doing and what you need. As the=20 documentation states, I designed this for my use in river ecosystem=20 modeling, but I'd like it to be as generally usable as possible. Cheers, J Nicolas Pernetty wrote: > Hi John, >=20 > Thank you for your answer. I've just downloaded the package and will > have a look on it next week. >=20 > About continuous system modeling, I'm personnaly involved in mechanics > system simulator (23 body linked together) and found it extremely > difficult to design the basic sets of equation without approximations. > Results are often hugely complex and slow. >=20 > We have tried to use readily available generic simulator (like > SimMechanics) but without success. >=20 > We decided to assume approximation, and thus managed to dramatically > simplify the set of equations, which we implemented 'by hand' in C. > Problem is that such approach has to be unique and repeated each time > someone has to design a simulator (because approximations are > different). >=20 > Another constraint I have is that some parts of the simulator has to be > run by data files. Indeed some parts are so difficult that it is useles= s > to try to represent it by equations. So some other people use different > method (like finite elements computation) and give me the result in the > form of data files. For instance for an airplane, I can have time vs > mass vs flow in the data file. >=20 > So my simulator is composed of equations, data files and some solver. > How can I design a generic program capable of handling every situations > is my current problem ! ;) >=20 > I would be happy to build on your project (if possible) and made it > available to the Python community... >=20 > I'll keep you informed of my progress, >=20 > Thank you again, >=20 > *********** REPLY SEPARATOR *********** >=20 > On Fri, 07 Oct 2005 08:07:34 0700, John Pennington Metta > <penningj@...> wrote : >=20 >=20 >>Nicolas, >>I'm working on Pyarie (pyarie.wikisophia.org), a system designed=20 >>(theoretically) to take an arbitrary set of equations and solve them,=20 >>tracking system or state variables, using a variety of solution >>methods (RungeKutta, etc). >> >>It's functional right now, but needs a great deal of cleaning up and >>has a lot of gaps (probability distributions, etc.). I was originally >> >>writing it for some modeling I'm doing for my thesis, but we took a=20 >>different path, so it's on a bit of a hold. >> >>There is one version that would probably be fine for you and which=20 >>works. It just requires the user to build his/her equations and=20 >>variables (along with timestep, output timestep, initial conditions,=20 >>etc) into two modules. After which the model will run, and spit all >>the state variables at each output timestep to a text file which you >>could graph (I linked it successfully with gnuplot at one point, and >>it ran and output graphs transparently). >> >>The link with SimPy is that continuous modeling is essentially >>discrete, in that we have to solve most equations at each timestep. >>So SimPy is the backend to the software, controlling the solution to >>the equation as a discrete processes at the given timestep. >> >>For a nonprogrammer, the current prealpha version is nonfunctional, >> >>but for you it would work fine (the programming you have to do is=20 >>essentially just entering your equations correctly). Please feel free >>to email me if there are any questions (which there will be), but I >>think there's still a sample model included (testmodel.py holds the >>equations, testsimulation sets up the initial variables, solver, >>timestep, etc.) >> >>Also, let me know what you'd like to, or do, change. I'm always=20 >>interested in making this better for others. Eventually I'll clean it >>up and publish it. >> >>Cheers, >>J >> >>p.s. I just noticed that some fiends completely erased every page of >>the wikibased home, so I'll have to modify that so noone can edit >>it, and replace all the information. >> >> >>Klaus Muller wrote: >> >>>Hi Nicolas! >>>There has been some work on continuous system simulation in Python: >>> >>>1) traffic simulation (using SimPy, too): >>>http://bitsko.slc.ut.us/blog/prtlrtsim.html >>>2) a paper presented at EuroPython 2005: >>>http://www.pythoninbusiness.org/ep2005/talk.chtml?talk=3D2273&track=3D= 646 >>>3) an excellent book: "Python Scripting for Computational Science" >>>by H. P. Langtangen (Springer) >>> >>>If you find out moe, please, let us all know. We may yet be able to >>>make SimPy a hybrid simulation package. >>> >>>Klaus M=FCller >>> >>> >>> >>> >>>>Original Message >>>>From: simpyusersadmin@...=20 >>>>[mailto:simpyusersadmin@...] On Behalf Of=20 >>>>Nicolas Pernetty >>>>Sent: Friday, October 07, 2005 1:16 AM >>>>To: simpyusers@... >>>>Subject: [Simpyusers] Continuous system simulation in Python >>>> >>>>Hello, >>>> >>>>I'm looking for any work/paper/ressource about continuous=20 >>>>system simulation using Python or any similar object oriented=20 >>>>languages (or even UML theory !). >>>> >>>>I'm aware that SimPy is for discrete event simulation, but=20 >>>>maybe you would have heard of any similr work on continuous=20 >>>>system. I would like to develop a generic continous system=20 >>>>simulator, and so would be eager to join any open source=20 >>>>effort on the subject. >>>> >>>>For instance, it would be useful for modelling an airplane=20 >>>>with all the dynamics (flight simulator). >>>> >>>>Python is my language of choice because of the keyword=20 >>>>'generic'. Being an object oriented dynamic language, it's=20 >>>>perfect for such a task. >>>>Unfortunately I'm a novice when it comes to object oriented=20 >>>>design and development, so I would prefer to start from=20 >>>>something already existent instead of starting from scratch. >>>> >>>>If you had any idea on the subject, I would be really glad to=20 >>>>discuss it with you. >>>> >>>>Thanks in advance, >>>> >>>> >>>> >>>>This SF.Net email is sponsored by: >>>>Power Architecture Resource Center: Free content, downloads,=20 >>>>discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl >>>>_______________________________________________ >>>>Simpyusers mailing list >>>>Simpyusers@... >>>>https://lists.sourceforge.net/lists/listinfo/simpyusers >>>> >> =20 John Metta (yes, my name has indeed changed...) http://oregonstate.edu/~penningj/ "A computer without windows is like a dog without bricks tied to its head." 
From: Klaus Muller <kgmuller@xs...>  20051008 15:22:39

I would use a class Machine with Resource instances A, B, and C (with capacities 1, 2 and 3, respectively) as attributes which get = instantiated in __init__.=20 Klaus M=FCller =20 > Original Message > From: simpyusersadmin@...=20 > [mailto:simpyusersadmin@...] On Behalf Of=20 > Steven H. Rogers > Sent: Saturday, October 08, 2005 2:44 PM > To: 'SimpyUsers List' > Subject: [Simpyusers] Modeling Clusters >=20 > I have a need to model machines with multiple types of=20 > resources, say one unit of type A, two of type B, and perhaps=20 > three of type C. A natural way to do this would be to=20 > aggregate the three resource types in a class. The model=20 > might have many of these machines. Is there a better way to=20 > to this with SimPy? >=20 > Regards, > Steve >=20 >  > Steven H. Rogers, Ph.D., steve@... > Weblog: http://shrogers.com/weblog > "He who refuses to do arithmetic is doomed to talk nonsense." >  John McCarthy > =20 >=20 >=20 >=20 >  > This SF.Net email is sponsored by: > Power Architecture Resource Center: Free content, downloads,=20 > discussions, > and more. http://solutions.newsforge.com/ibmarch.tmpl > _______________________________________________ > Simpyusers mailing list > Simpyusers@... > https://lists.sourceforge.net/lists/listinfo/simpyusers >=20 
From: Steven H. Rogers <steve@sh...>  20051008 12:44:14

I have a need to model machines with multiple types of resources, say one unit of type A, two of type B, and perhaps three of type C. A natural way to do this would be to aggregate the three resource types in a class. The model might have many of these machines. Is there a better way to to this with SimPy? Regards, Steve  Steven H. Rogers, Ph.D., steve@... Weblog: http://shrogers.com/weblog "He who refuses to do arithmetic is doomed to talk nonsense."  John McCarthy 
From: Steven H. Rogers <steve@sh...>  20051008 12:36:25

Klaus Muller wrote: > Hi all! > I will be offline (on holiday) from October 9 till November 7. Natural= ly, I > will answer all my mail then. So, keep writing! >=20 > Klaus M=FCller Have a good holiday, Klaus. Thanks for all the hard work. Regards, Steve =20 Steven H. Rogers, Ph.D., steve@... Weblog: http://shrogers.com/weblog "He who refuses to do arithmetic is doomed to talk nonsense."  John McCarthy 
From: Klaus Muller <kgmuller@xs...>  20051008 10:25:07

Hi all! I will be offline (on holiday) from October 9 till November 7. = Naturally, I will answer all my mail then. So, keep writing! Klaus M=FCller 
From: John Pennington Metta <penningj@en...>  20051007 15:08:03

Nicolas, I'm working on Pyarie (pyarie.wikisophia.org), a system designed=20 (theoretically) to take an arbitrary set of equations and solve them,=20 tracking system or state variables, using a variety of solution methods=20 (RungeKutta, etc). It's functional right now, but needs a great deal of cleaning up and has=20 a lot of gaps (probability distributions, etc.). I was originally=20 writing it for some modeling I'm doing for my thesis, but we took a=20 different path, so it's on a bit of a hold. There is one version that would probably be fine for you and which=20 works. It just requires the user to build his/her equations and=20 variables (along with timestep, output timestep, initial conditions,=20 etc) into two modules. After which the model will run, and spit all the=20 state variables at each output timestep to a text file which you could=20 graph (I linked it successfully with gnuplot at one point, and it ran=20 and output graphs transparently). The link with SimPy is that continuous modeling is essentially discrete,=20 in that we have to solve most equations at each timestep. So SimPy is=20 the backend to the software, controlling the solution to the equation as=20 a discrete processes at the given timestep. For a nonprogrammer, the current prealpha version is nonfunctional,=20 but for you it would work fine (the programming you have to do is=20 essentially just entering your equations correctly). Please feel free to=20 email me if there are any questions (which there will be), but I think=20 there's still a sample model included (testmodel.py holds the equations,=20 testsimulation sets up the initial variables, solver, timestep, etc.) Also, let me know what you'd like to, or do, change. I'm always=20 interested in making this better for others. Eventually I'll clean it up=20 and publish it. Cheers, J p.s. I just noticed that some fiends completely erased every page of the=20 wikibased home, so I'll have to modify that so noone can edit it, and=20 replace all the information. Klaus Muller wrote: > Hi Nicolas! > There has been some work on continuous system simulation in Python: >=20 > 1) traffic simulation (using SimPy, too): > http://bitsko.slc.ut.us/blog/prtlrtsim.html > 2) a paper presented at EuroPython 2005: > http://www.pythoninbusiness.org/ep2005/talk.chtml?talk=3D2273&track=3D= 646 > 3) an excellent book: "Python Scripting for Computational Science" by H= . P. > Langtangen (Springer) >=20 > If you find out moe, please, let us all know. We may yet be able to mak= e > SimPy a hybrid simulation package. >=20 > Klaus M=FCller >=20 >=20 >=20 >>Original Message >>From: simpyusersadmin@...=20 >>[mailto:simpyusersadmin@...] On Behalf Of=20 >>Nicolas Pernetty >>Sent: Friday, October 07, 2005 1:16 AM >>To: simpyusers@... >>Subject: [Simpyusers] Continuous system simulation in Python >> >>Hello, >> >>I'm looking for any work/paper/ressource about continuous=20 >>system simulation using Python or any similar object oriented=20 >>languages (or even UML theory !). >> >>I'm aware that SimPy is for discrete event simulation, but=20 >>maybe you would have heard of any similr work on continuous=20 >>system. I would like to develop a generic continous system=20 >>simulator, and so would be eager to join any open source=20 >>effort on the subject. >> >>For instance, it would be useful for modelling an airplane=20 >>with all the dynamics (flight simulator). >> >>Python is my language of choice because of the keyword=20 >>'generic'. Being an object oriented dynamic language, it's=20 >>perfect for such a task. >>Unfortunately I'm a novice when it comes to object oriented=20 >>design and development, so I would prefer to start from=20 >>something already existent instead of starting from scratch. >> >>If you had any idea on the subject, I would be really glad to=20 >>discuss it with you. >> >>Thanks in advance, >> >> >> >>This SF.Net email is sponsored by: >>Power Architecture Resource Center: Free content, downloads,=20 >>discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl >>_______________________________________________ >>Simpyusers mailing list >>Simpyusers@... >>https://lists.sourceforge.net/lists/listinfo/simpyusers >> =20 John Metta (yes, my name has indeed changed...) http://oregonstate.edu/~penningj/ "A computer without windows is like a dog without bricks tied to its head." 
From: Klaus Muller <kgmuller@xs...>  20051007 08:42:54

Hi Nicolas! There has been some work on continuous system simulation in Python: 1) traffic simulation (using SimPy, too): http://bitsko.slc.ut.us/blog/prtlrtsim.html 2) a paper presented at EuroPython 2005: http://www.pythoninbusiness.org/ep2005/talk.chtml?talk=3D2273&track=3D6= 46 3) an excellent book: "Python Scripting for Computational Science" by H. = P. Langtangen (Springer) If you find out moe, please, let us all know. We may yet be able to make SimPy a hybrid simulation package. Klaus M=FCller > Original Message > From: simpyusersadmin@...=20 > [mailto:simpyusersadmin@...] On Behalf Of=20 > Nicolas Pernetty > Sent: Friday, October 07, 2005 1:16 AM > To: simpyusers@... > Subject: [Simpyusers] Continuous system simulation in Python >=20 > Hello, >=20 > I'm looking for any work/paper/ressource about continuous=20 > system simulation using Python or any similar object oriented=20 > languages (or even UML theory !). >=20 > I'm aware that SimPy is for discrete event simulation, but=20 > maybe you would have heard of any similr work on continuous=20 > system. I would like to develop a generic continous system=20 > simulator, and so would be eager to join any open source=20 > effort on the subject. >=20 > For instance, it would be useful for modelling an airplane=20 > with all the dynamics (flight simulator). >=20 > Python is my language of choice because of the keyword=20 > 'generic'. Being an object oriented dynamic language, it's=20 > perfect for such a task. > Unfortunately I'm a novice when it comes to object oriented=20 > design and development, so I would prefer to start from=20 > something already existent instead of starting from scratch. >=20 > If you had any idea on the subject, I would be really glad to=20 > discuss it with you. >=20 > Thanks in advance, >=20 >=20 >  > This SF.Net email is sponsored by: > Power Architecture Resource Center: Free content, downloads,=20 > discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl > _______________________________________________ > Simpyusers mailing list > Simpyusers@... > https://lists.sourceforge.net/lists/listinfo/simpyusers >=20 
From: Nicolas Pernetty <nicopernetty@ya...>  20051006 23:12:07

Hello, I'm looking for any work/paper/ressource about continuous system simulation using Python or any similar object oriented languages (or even UML theory !). I'm aware that SimPy is for discrete event simulation, but maybe you would have heard of any similr work on continuous system. I would like to develop a generic continous system simulator, and so would be eager to join any open source effort on the subject. For instance, it would be useful for modelling an airplane with all the dynamics (flight simulator). Python is my language of choice because of the keyword 'generic'. Being an object oriented dynamic language, it's perfect for such a task. Unfortunately I'm a novice when it comes to object oriented design and development, so I would prefer to start from something already existent instead of starting from scratch. If you had any idea on the subject, I would be really glad to discuss it with you. Thanks in advance, 