Mathematica

Using numbers close to to zero in Mathematica version 6
On Apr 9, 12:35 am, "Ted Ersek" <ers...(a)md.metrocast.net> wrote: What does Mathematica version 6 give when the following is evaluated? Here (x) is 'zero' with 80 digits of accuracy. x = SetAccuracy[0, 80]; { Abs[x] < 10^-900, Positive[x], Negative[x], NonPositive[x], NonNegative[x] }//InputForm ... 11 Apr 2010 04:45

Change of function in an ODE
Hi, I'm solving DSolve[r^4 R''''[r] + 2 r^3 R'''[r] - r^2 R''[r] + r R'[r] - L^4 r^4 R[r] == 0, R[r], r] // Simplify Now, I would like to make the substitution R[r]=r^2 Log[r] G[r], formulate the equation for G[r] and solve it. What's the proper syntax for that? Thanks, Sam ... 12 Apr 2010 23:39

Number format on axes
Anyone know how to directly format the numbers next to the ticks on a DateListPlot or other to appear as AccountingForm? ... 11 Apr 2010 04:44

Format InputField -> Right ?
Does anyone know how to make the expression in an InputField[Dynamic[x]] appear right justified? ... 12 Apr 2010 06:59

Surprising behaviour with nested pure functions and
Hello, the experiment is very interesting; my point of view: In[1]:== Function[{x}, Function[{y}, x + y]] Out[1]== Function[{x}, Function[{y}, x + y]] In[2]:== %[2y] Out[2]== Function[{y$}, 2 y + y$] therefore the (Mathematica evaluation process) rule (lets call it RULE1) is, that local variable... 10 Apr 2010 08:00

How do you get Mathematica to evaluate "Floor" to give a number?
In[1]:= J = 367*y + Floor (7*(y + Floor ((m + 9)/12))/4) + Floor (275*m/9) + da + 1721013.5 Out[1]:= 2.44254*10^6 + (2200 Floor)/9 + 7/4 Floor (1966 + (17 Floor)/12) How do you get Mathematica to evaluate "Floor" to give a number? ... 12 Apr 2010 06:59

List Manipulation: Conditionally changing y value
n=5; x=RandomReal[{0,1}, n]; y=RandomReal[{0,1}, n]; pts=Thread[{x,y}]; {a,b}={.25,.75}; filtered1=If[a<#[[1]]<b,{1,0}#,#]&/@pts or filtered2={1,If[a<#[[1]]<b,0,1]}#&/@pts or filtered3={1,1-Boole[a<#[[1]]<b]}#&/@pts filtered1==filtered2==filtered3 True Bob Hanlon ---- Charles Ko... 10 Apr 2010 06:56

Simultaneous Nonlinear Data Fits
Hello everyone, A small statement of my problem: I have 4 data sets consisting of spectroscopic data (intensity vs frequency data). The data contain resonant peaks that are fit with the modulus squared of a sum of complex functions (one for each peak for a total of 6 peaks) and is such that I must use nonl... 20 Apr 2010 15:53

Symplify Table
I want to subtract array A by 1/2 array B and put it in array C. I need something like this except more complicated later. This is what I have thus far: C:=C=Simplify[Table[A[i]-1/2*B[i],{i,1,9}]] ... 12 Apr 2010 06:59

How to enter an integral in a formula and have mathematica
Hi, Jim, I am not quite sure that I've got your question right, but in case I did, execute this: (* Here it is assumed that your (stuff)=1 and your g(s,x)=exp(-x*s^2). This can be changed *) f1[x_] := 1 + \!\( \*SubsuperscriptBox[\(\[Integral]\), \(0\), \(1\)]\(Exp[\(-x\)* \*SuperscriptBox[\(s\), \(2\)]] \[D... 10 Apr 2010 06:56