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6h
comment Find Root Iteration
mysum is not even a function of x in your sample
1d
comment How to plot several functions without jumping? (multiple eigenvalues of a system as functions of 2 parameters)
@altroware fixed that issue i think - verified only with 9 which it turns out has the Indexed function (undocumented).
1d
comment Numerically integrating a list-valued function
that issue is somewhat avoided if you do : foo[x_?NumericQ] :=foo[x]= {x^2, x^3} ( though not entirely in case NIntegrate wants to evaluate the expressions at different points )
1d
comment Numerically integrating a list-valued function
note this is evaluating each of the list expressions twice for each x .. so it illustrates the issue but isn't likely a good approach for performance reasons.
Aug
15
comment Finding average error of the data
mike, show the LinearModelFit code you tried that fails.
Aug
13
comment How to plot several functions without jumping? (multiple eigenvalues of a system as functions of 2 parameters)
i guess the warning i surpressed got elevated to an error. i dont have 10 to work on it though
Aug
13
comment ContourPlot // Heat Function visualization
dont mess with manipulate until you get the basic plot working
Aug
13
comment Error with “Newton's method” in Wellin's Mathematica book
my wag older mma versions didnt flag the issue with a warning (dont know how old that book is)
Aug
12
comment Measuring time complexity of a method
all you can do without acess to the details of the code is emperically evaluate for various n using timing and look at the trend
Aug
10
comment Read and write files
you should keep everything that you don't change in string format start with Import[file,{"Text","Lines"}]. Then you need to cook up the appropriate string operations to make the desired changes.
Aug
7
comment How to integrate a function which is only known at discrete points
reference.wolfram.com/language/ref/Interpolation.html
Aug
5
comment Matrix containing ellipse
note Rasterize does not (evidently) have an option to make a 1-bit image, so you end up with gray values at the edges of the ellipse. You could use Round instead of MorphologicalComponents however. (still a tad slower than Image ).
Aug
5
comment Integral too slow and with conditionals
you can do $Assumptions = {(x | y) \[Element] Reals && x > 0 && a > 0} instead of giving the option to Integrate (be aware though that only functions that take an assumptions argument actually use the $Assumptions variable.. )
Aug
5
comment the winding number for the circle map (Arnold tongue)
@xzczd : works for me (and about 50% faster ). Mean[Nest[# + a - k Sin[2 Pi #] &, RandomReal[1, Round[m]], Round[n]]/n]
Aug
5
comment Edge finite elements in Mathematica
is this a 'new in 10' question? (what "Finite Element capabilities " are you talking about? )
Aug
5
comment the winding number for the circle map (Arnold tongue)
good call +1!. Can you generate a figure showing regions where the result is "essentially" independent of the input?
Aug
4
comment Calculate integral in limit of very large coefficient
The second is zero: Limit[ Integrate[ Exp[ -alpha Sqrt[x] ], {x, 0, y}] , alpha -> Infinity, Assumptions -> {y > 0}]. The first you probably need to do numerically
Aug
4
comment the winding number for the circle map (Arnold tongue)
Have you plotted this? I still get a result that looks more like @Chenminqi's initial result that the figure on the wiki page. (I'm beginning to doubt the validity of the wiki page figure in the neighborhood of a~1/2 , b~3/5 )
Aug
4
comment the winding number for the circle map (Arnold tongue)
after taking a deeper look, I think someone with sufficient expertise should clarify what the "is to be interpreted" statement is supposed to mean on the wikipedia page..
Aug
3
comment the winding number for the circle map (Arnold tongue)
where \theta is to be interpreted as polar angle such that its value lies between 0 and 1. have you tried shifting the result on each iteration?