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Dec
17
comment How to convert a string of number into real numbers without precision loss
what is StringToDouble ?
Dec
15
awarded  Enlightened
Dec
15
awarded  Nice Answer
Dec
12
comment Assigning an equation as a variable
@AshleyJames, ok add N@Grid
Dec
12
revised Assigning an equation as a variable
added 2 characters in body
Dec
12
answered Assigning an equation as a variable
Dec
9
comment Inversion algorithm for Laplace Domain
Why do you put [] around names of your variables? like this [CurlyPhi] = 0.1; [Omega] = 10^-6 did you read that somewhere in the documentation? ALso it is bad idea to use UpperCaseFirstLetterForYourVariablesAndSymbols since this can conflict with Mathematca's own and also can be confusing to the reader. lowerCaseFirstLetterWillWorkJustAsWell
Dec
9
comment Plotting equations of motion of a baseball
I know that offcourse. But the problem is that when copying it back from here to my notebook, the subscripts stay in the long form. Hence impossible to read the code. That is why it is not good idea to use it subscripts in code. Become hard to move around as plain text code.
Dec
9
comment Plotting equations of motion of a baseball
can't read your code with all this subscript this and subscript that. Sorry. Can't read code, can't help.
Dec
8
comment Prime factor counting function
why the decimal point? in count3[100000.] ?
Dec
8
comment Prime factor counting function
and if you just want the count, then something like: k = 0; Do[If[PrimeOmega[n] == 3, k++], {n, 1, 1000}];
Dec
8
comment Prime factor counting function
or use Do as in Reap@Do[If[PrimeOmega[n] == 3, Sow[n]], {n, 1, 100}] which is fast also. Not as fancy as your code though but Do is really fast, and I think it qualifies sort of as being functional programming, but may be not pure functional, just a little bit functional.
Dec
8
comment Prime factor counting function
Why not just use a simple table? Table[If[PrimeOmega[n] == 3, n, Sequence @@ {}], {n, 1, 100}] gives {8, 12, 18, 20, 27, 28, 30, 42, 44, 45, 50, 52, 63, 66, 68, 70, 75, 76, 78, 92, 98, 99} and it seems faster than what you have using a quick test. May be you can double check
Dec
8
comment Prime factor counting function
you can start by skipping the prime numbers themselves. maybe that will speed it up a tiny bit. Your code is too advanced for me, having hard time knowing wHat this do Not[FreeQ[PrimeOmega[n], _?(# == 3 &)]] ? btw, bad idea to use UpperCase first letter for your function names. They look like build-in commands.
Dec
8
comment Does Mathematica know if an integral is convergent or not?
I think yes, M would have said it does not converge if does not. But you can check. Assuming[m >= 1 && q >= 1 && k >= 1 && m \[Element] Integers && k \[Element] Integers, Limit[Exp[-2*\[Pi] (m*q*Sqrt[\[Lambda] + 1/4] + k*Sqrt[\[Lambda]])], \[Lambda] -> Infinity]] gives zero. (you need to fix Pi[] error in your code. still there) since integrand goes to zero, there is a good chance the area below the function is zero. But this is for the math people to confirm.
Dec
8
comment Does Mathematica know if an integral is convergent or not?
Yes, but Pi is not a function. You can't write Pi[....], well you can, but it makes no sense.
Dec
8
comment Does Mathematica know if an integral is convergent or not?
You still have error. You type Pi [] where you need to use Pi () for grouping. Do not use [] to group expression. see Pi[ m*q in your code... Pi is not a function. Your integrand is too hard for analytical solution. Removing the second Sqrt[lambda] helped. !Mathematica graphics
Dec
8
comment Does Mathematica know if an integral is convergent or not?
see !Mathematica graphics You can't write m[Element] Integers, you can't write Sqrt[[Lambda]] etc...as I said, W/A accepts messy human input. But Mathematica needs exact syntax. May be in version 10, when the system becomes WL and unified, then your input will work. But now in version 9.01 it is giving errors.
Dec
8
revised Different results for integration using Mathematica and MATLAB
deleted 206 characters in body
Dec
8
answered Different results for integration using Mathematica and MATLAB