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1d
comment Copy files existing in different directories under the same directory
reference.wolfram.com/language/ref/CopyFile.html
1d
comment Simplifying vector expressions
the fundamental problem is that mathematica does not recognize u as a vector , and there is unfortuantely no simple work around. You should look at this: reference.wolfram.com/language/tutorial/SymbolicTensors.html but before going too deep be aware only certain functions recognize symbolic vector concepts (D in particular does not )
1d
comment Is 450 lines of code in one block too much?
FWIW it works ok with v9/windows. (I just copied the code from the post).
1d
comment Strange integration
$RecursionLimit = Infinity; causes it to keep running..not optimistic it will yield a result though.
1d
comment Strange integration
FYI the expression simplifies to: (Cos[x]-Sinc[x])/(Cosh[x]+Sinh[x]-1). Same result on integration though :(
1d
comment simplifying the range of two definite integrals
right of course, caught me commenting before my second cup of coffee. I'll point out you can show this more simply as Integrate[ f[x] , {x, 0, 1} ] + Integrate[ f[x] , {x, 1, t } ] does not simplify under any assumptions I can think of.
1d
comment simplifying the range of two definite integrals
mathematically you need 0<=t<=1 to consolidate that to a single integral (from 0 to t). (I don't know if mathematica will do the simplify even under that assumption though)
1d
comment simplifying the range of two definite integrals
to further simplify you need to know something about the range of t. try specifying assumptions.
Oct
20
comment Colorize Grayscale Image
about 15x faster than my ImageApply :(.
Oct
20
comment Find all roots in range
just looking at the comments @matin maybe should clarify the question as he seems to be aware of ZetaZero and looking for an alternative for some reason.
Oct
20
comment Find all roots in range
Solve gives the result that the roots are +/-Im[ZetaZero[i] - 1/2] for any i>0 (plus the trivial roots) .. at least as I read the question/comments he wants to find the roots without using ZetaZero
Oct
20
comment Find all roots in range
Note this just returns a result in terms of ZetaZero..
Oct
20
comment How do I get a Do function to create a list?
have a look at Reap/Sow
Oct
20
comment How do I get a Do function to create a list?
i'm going to guess you have a Print[] in the do?
Oct
20
comment Open a .txt file in Mathematica
posting the first dozen or so lines from the file might be useful...
Oct
20
comment Open a .txt file in Mathematica
change the extension to nb?
Oct
19
comment using memoization with conditional statement
for your last example do Downvalues[myfunction] after plotting. i expect you will see that you are seperately memorizing the result for each v.
Oct
18
comment Loops for Unit Root Test
UnitRootTest/@px seems to be all you need..
Oct
18
comment Loops for Unit Root Test
does that RandomReal work? Its not a documented usage (likely you mean RandomVariate )?
Oct
18
comment why CopyFile cannot overwrite existing file?
i don't think an undocumented option should be considered a "bug". There may be legitimate reasons, especially for a system related function it may not be robustly tested for all system combinations.