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bio website mathprogramming-intro.org
location St. Petersburg, Russia
age 37
visits member for 2 years, 3 months
seen 6 hours ago

Ok, an obligatory note: opinions expressed here are mine and not those of my employer.


Apr
10
comment RLink Java(TM) platform has stop working
What makes you think that you are constructing a valid R function with this string? I looked at it, and it contains e.g. Mathematica Log functions etc. Besides, this is most definitely not the recommended way to construct an R function with RLink. What you should be doing is to transfer data to R, and then construct the R function to operate on that data.
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Funzies I have added a section on exact solution on infinite interval. It can serve as a starting point of some better approach, something like a perturbation theory in the "proximity of the finite large interval to infinite interval", or, smallness of the coefficient const.
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Szabolcs Oh, I see what you meant. I agree with this.
Apr
10
revised Solving a nonlinear, second order d.e. in Mathematica
Added a solution for infinite interval
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Szabolcs Any differential operator includes boundary conditions in its definition. Therefore, there is no translational invariance, since it is obviously broken by the boundary conditions (finite region).
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Funzies I've made some mistake in my calculations, corrected now. It only affected the formulas and constants, the new plots are visually indistinguishable from the old ones. But of course, you should use the new formulas. Sorry for the confusion.
Apr
10
revised Solving a nonlinear, second order d.e. in Mathematica
Corrected a mistake in computations
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Funzies Actually, it seems I've made a mistake. Will correct shortly.
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
@Funzies You are welcome :). It remains to check that the numerical solution is correct, by substituting into the equation, but that may require extra precision.
Apr
10
answered Solving a nonlinear, second order d.e. in Mathematica
Apr
10
comment How to protect functions in a Mathematica Package?
@Pillsy I guess, locking here is used in the context of protecting the intellectual property. This is how I interpreted this question anyway.
Apr
10
comment Solving a nonlinear, second order d.e. in Mathematica
What makes you think that there is a solution for your boundary conditions? Even for a linear case, this is only guaranteed for initial-value problems, where you'd provide values of s and its derivative at one and the same point.
Apr
10
revised How to protect functions in a Mathematica Package?
added 322 characters in body
Apr
10
comment How to protect functions in a Mathematica Package?
@LoryLory The problem with Needs, as halirutan just pointed out, is that this does not help you during the development, where you do want your package to be reloaded to pick up the changes, rather than just its context brought up to the $ContextPath - which is what Needs does for already loaded packages.
Apr
10
answered How to protect functions in a Mathematica Package?
Apr
9
comment relative directory paths within a mathematica package/what directory does a mathematica package see as local?
See also this
Apr
9
answered Selecting items in a list based on multiple tests
Apr
9
comment What is the most efficient way to map a linked list?
@Pillsy Thanks :) Also for the accept, and for asking this question in the first place. I am myself quite interested in using linked lists more, and this was a nice opportunity to practice / learn a bit more about this.
Apr
9
revised Wrapping a data selection in Mathematica
Added a section on packed arrays
Apr
9
answered Wrapping a data selection in Mathematica