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1d
comment Why do big-O terms disappear in definite integrals since Mathematica 9?
good call, see edit..
1d
comment how to speedup subpixel registration
@SimonWoods, thanks but not available (v10 think I guess?). Incidentally, setting the option "Transformation" -> "Translation" yields utter garbage results (9.0.1), even though the automatic setting clearly uses a simple translation..
2d
comment how to speedup subpixel registration
@nikie Thanks! you should post that as an answer. BTW FindMinimum produces a slightly less accurate result for some reason, but for present purpose that's not an issue.
Oct
23
comment Copy files existing in different directories under the same directory
reference.wolfram.com/language/ref/CopyFile.html
Oct
22
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 )
Oct
22
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).
Oct
22
comment Strange integration
$RecursionLimit = Infinity; causes it to keep running..not optimistic it will yield a result though.
Oct
22
comment Strange integration
FYI the expression simplifies to: (Cos[x]-Sinc[x])/(Cosh[x]+Sinh[x]-1). Same result on integration though :(
Oct
22
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.
Oct
22
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)
Oct
22
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.