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comment How to get integer/rational and real eigenvectors to be the same?
the sign change is not explicitly mentioned in the link, but it is essentially the same issue. You can "fix" by choosing a convention that suits you such as multiplying by the Sign of the largest magnitude component. Look at the answer here math.stackexchange.com/questions/235396/eigenvalues-are-unique
15h
comment Generate a list of values with equal number of each value
your formula is right but not the number: 32 (32!/(16!)^2) == 19234572480 (off by 1/2 .. )
17h
comment complicated Numerical Integration, FEM application
mathematica.stackexchange.com/questions/34657/…
17h
comment complicated Numerical Integration, FEM application
the other thing you need to take that inner integral and turn it into a function that takes only numeric arguments (eq inner[x2_?NumericQ, y2_?NumericQ, xz_?NumericQ, yz_?NumericQ] := NIntegrate[...] . Probably add ?NumericQ to the arguments of t and B2 as well
18h
comment complicated Numerical Integration, FEM application
your definition trans:= does not create a function that takes four arguments. You should do trans[x1_,y1_..] (Its not immediately obvious what args should be)
1d
comment How to get more accurate orthonormal eigenvectors?
you are asking for output that is higher precision than the input
1d
comment draw graphics in cycle
lots of basic syntax errors, where to begin?
1d
comment Solving nonlinear system by newton method
This question appears to be off-topic because it is not about mathematica
1d
comment Recover data points from RGBColor of known ColorScheme
The issue is that color scheme has a region of a constant channel (Red==0 for z<1/4), so Solve fails.
1d
comment Recover data points from RGBColor of known ColorScheme
Nice +1. Just to make some extra work it doesn't work quite right with some other color schemes eg. ColorData["AvocadoColors"] (random choice.). I'm guessing it needs just a little tweak to make more robust.
2d
comment Randomly selecting and reinserting a subset of elements in a list
nit picking i think you need to add 1 to the random range or you'll never insert at the end
2d
comment How can I use a For loop in a recursive function?
your loop doesnt get past k=0 since it immediately hits Return
2d
comment Enter exact rational numbers easily with decimal notation
The point is to work with the actual text entered to avoid some of the issues raised in the comments arising from conversion to/from machine precision. (As a practical matter those issues may not be important, and using $Pre like that is clearly cleaner and more robust )
Apr
15
comment Deciding lambda and integrate a function
appears to be not about mathematica and not fully explained to migrate to math.so either. (looks like a "part" of a seperable pde problem)
Apr
14
comment How can I calculate the limit without using the L'Hopital's rule
i'm sure its trivial to show that the series converges, but i'd think you need to show that step to offer this up as proof.
Apr
14
comment combining plots
you can very well do Show[{gr[...],Plot[..]}] (many ways to skin this cat)
Apr
14
comment How to produce functions
he answered the literal question, but its not likely the best approach to your problem. Using f[1][x],f[2][x].. for example would be cleaner and avoid messing with symbol names.
Apr
14
comment Errors of machine precision
note he claims he hasn't used that expression. @Meqdad you need to show the code you are using if you want further help.
Apr
14
comment Vector-calculus
BinCounts might be better (this will break if any count happens to be zero)
Apr
14
comment Vector-calculus
see Partition and Tally