The following Mathematica codes is programmed to resolve differential equations founded by Lagrange method.
Five generalized coordinates (q1[t],q2[t],q3[t],q4[t] and q5[t]) are introduced to characterize the motion of the system. According to the physical processes, the boundary conditions (init...
@Rojo Because the work is about building a sophisticated UI in Mma. And I really think Mma's FE is too convoluted and not robust enough. And then you have all those incompatibilities from version to version
DatabaseLink: I have an in memory database in hsqldb that is taking 1.7GB of ram. I dropped the "big table", but it still takes up that much memory. Any ideas?
(Solved)
Wow, I somehow managed to make the FrontEnd disappear, keeping the notebooks open
hello; simple question: in other languages, you can define a function say, function() which takes flags; so that its defined as function(x,flag1=,flag2=)...
so it makes it easy to have many arguments and not care about the order at which they are called
@chris Here's an example (middle of the answer) where a function I wrote was turned into all options (with a couple of improvements along the way). I am not a fan of all option functions, I think it hinders usability, but I believe Faysal uses it quite regularly, so whatever works for you.
@acl This is very important and not very well known, I think. I used to write only a plain usage message. Once, when sending something to someone, I decided to change it to f::usage = "f[x,y] blah blah" so that it is clearer for the other person. I was surprised when I did cmd-shift-k (which was an accident... I meant to do only cmd-k) and it auto completed the template. Now I always write messages this way...
@R.M when you have functions with many arguments it can be very useful, yes (so long as you don't change the order of the args in the usage message by mistake)
All, would be grateful for any suggestions of good reviews for symplectic integrators for Hamiltonian systems (preferably physicist-oriented but not a problem if not)
As you asked for source code: From HERE you can download MATLAB and FORTRAN code for symplectic methods for Hamiltonian systems and symmetric methods for reversible problems. And a lot of other methods for dealing with diff equations too.
And in THIS paper you can find the description of the alg...
@J.M.: sometimes I can find you in the list of chat users, and sometimes not. I think someone is playing around with the code for the two letter, punctuated names.
