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location Champaign, IL
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visits member for 2 years, 8 months
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8h
comment How to figure out whether a nonlinear inequality holds or not
FindInstance is a good function to check for existence of a counterexample. FindInstance[(1 + g)^(-m - w) ((a - (-1 + a) (1 + g)^m) (1 + p q) Q - (1 + g)^w ((-1 + p) q + (1 + g)^m (1 + q)) Q) < 0 && 0 < g && 0 < w && 0 < m && 0 < Q, {g, w, m, Q, p, a, q}] gives one quite quickly.
1d
comment How to get the series coefficient of a function defined by a differential equation
Sorta' defeats the concept of developing a local series solution if you get a closed form instead. (Just saying..)
1d
answered How to get the series coefficient of a function defined by a differential equation
2d
comment How can I resolve the insufficient memory to complete the computation problem for solving function with iterated variables?
It probably means that in attempting to validate that solution, Solve noted both a numerator and denominator (approximately) vanishing. So it could not tell whether the solution was legitimate or a parasite.
2d
comment How can I resolve the insufficient memory to complete the computation problem for solving function with iterated variables?
If you post a working self-contained code this might be more amenable to analysis. That way others do not need to guess at values for RA1[[whatever]], or read through the code to figure out dimensions, or what are the variables in need of values. That's asking a lot of ones readers.
2d
comment Find arc length
If you define f sans Re[], and then use Re[] on the max, min, plot, and NIntegrate, they will all work. As it stands, D has trouble with the Re because it is not an analytic function.
2d
comment Why is it not allowed to define vectors of variables in a scoping construct?
Those scoping constructs take symbols as elements of the first argument, optionally setting them to values. Whether that could be extended to nested lists is an open question I guess, but the fact is the language does not support that at this time.
2d
revised Finding all paths of certain length between vertices in path graph, non-simple ones too
added faster graph variant
2d
awarded  Nice Answer
2d
comment 12th International Mathematica Symposium
It's an important ad, but I agree meta is the right venue (though I wish the rules were a bit more indulgent in this regard).
Sep
14
answered Maximize violating constraints
Sep
13
revised Finding all paths of certain length between vertices in path graph, non-simple ones too
added a graph-based method
Sep
13
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
Wow. And here is some description which you may already have read. Was he ever where anyone thought he was?
Sep
13
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
I still liked your ILP-based method. I even cribbed from it (still no match for the faster methods though).
Sep
13
revised Finding all paths of certain length between vertices in path graph, non-simple ones too
added 1319 characters in body
Sep
13
comment How to make a new analytic function work seamlessly with Mathematica's analysis functions?
There will be places in internal Limit (and other) code that check for that attribute, and treat nonnumeric "functions" as being, in effect, inert. So if you have myFunction[x], that might be seen as something for Limit et al to regard as constant rather than being functionally dependent on x.
Sep
12
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
Yes I do. But which Floyd? Patterson? Mayweather? Pretty Boy? (Patterson was a bit small for a heavyweight, but he won a gold medal as a middleweight in Helsinki).
Sep
12
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
Google images is suggesting Nicolino Locche, but my guess seems to be second on their list. Hard to tell.
Sep
12
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
Ah yes. Well do I remember that segment. Now let me ask:??
Sep
12
comment Finding all paths of certain length between vertices in path graph, non-simple ones too
Those Or constraints scare me. Not as much as the thought of you with half a sheep. But close.