What is Mathematica: Definition and 1000 Discussions

Wolfram Mathematica is a software system with built-in libraries for several areas of technical computing that allow symbolic computation, manipulating matrices, plotting functions and various types of data, implementation of algorithms, creation of user interfaces, and interfacing with programs written in other programming languages. It was conceived by Stephen Wolfram and is developed by Wolfram Research of Champaign, Illinois. The Wolfram Language is the programming language used in Mathematica.

View More On Wikipedia.org
Recent contents Top users
  1. kq6up

    Mathematica Replacing Mass in Equations of Motion: Quick Mathematica Question

    I have equation of motion that our instructor wants to replace one or both of the masses with a negative mass in Mathematica. I tried m1=-m1, but I get an infinite recursion. What is the best way to do this? The equations of motion is a monster, so I don't really want to do this by hand...
  2. T

    MATLAB Is MATLAB's Implementation of Spherical Harmonics Incorrect?

    Hey guys, This is my first post here, so I will apologize in advance in case I'm posting this in the wrong section. I wrote a very simple function to calculate spherical harmonics in matla, and I used this function during 3 years. Yesterday I found that the function was actually wrong, and...
  3. M

    How to compute a tri-coherence

    Dear all, I have time-series data, from which I would like to compute the tricoherence. After some googling, it seems that I will have to write my own code. But before I begin, let me ask this. Do anyone here know of a code, library (fortran, c), module (python, matlab, IDL, mathematica)...
  4. J

    Is There a Free Alternative to Mathematica for Complex Calculations?

    I am trying to integrate a very messy expression using Wolfram online integrator but I get the message: "You need to use Mathematica to evaluate this expression". The online integrator works only for relatively simple expressions. Unfortunately I do not have a license for Mathematica. Any...
  5. M

    Maple Math Plotting Software for Electrical Engineering

    Hi All: I am an electrical engineering undergrad. I would like to learn a math plotting software which would be helpful in visualizing topics in advanced calculus (my immediate need). It would also be helpful if the math plotting software was of some use in electrical engineering, but this is...
  6. N

    Software for generating magnetic field within iron

    Dear All, I need to design a magnetized iron calorimeter detector (HEP ex). There will be current coils (in the vertical plane) that will generate x-y magnetic field within iron. Given the detector boundaries and exact locations of the coils (i.e. all the B.C.s), I need to obtain the...
  7. N

    Plotting results from for loop

    Plotting results from "for" loop Hello, I have a problem which it seems I couldn't solve. I have "for" loop which gives results of some calculations as, say, vectors with two coordinates. What I want is to plot the result as a point in the xy plane. This loop goes on and on with the...
  8. Ascendant78

    Useful ipad apps for physics majors?

    At this point, I have about $45 credit in my iTunes account from gift cards given to me for Christmas. I was wondering if there are any useful apps out there that I can get for physics? Whether they are good now for while I am in college, good for work in the field post-college, or both. For...
  9. H

    How can I solve my differential equation with Mathematica?

    Hi, I can't quite figure out what I'm doing wrong here. I tried restarting mathematica as well which is what fixed my previous problem Clear[eqn, soln, u, x, y] eqn = D[u[x, y], {x, 2}] + D[u[x, y], {y, 2}] == 0; soln = NDSolve[{eqn, u[x, 0] == Sin[x], u[0, y] == 0, u[1, y] == 0}, u[x...
  10. V

    MATLAB Maximizing the fraction of two integrals using matlab

    EDIT: I left out something of major importance, I want to maximize with respect to a! Good day, I've run into an issue in solving a certain problem with matlab, and I was hoping if anyone could help me out. I am relatively new to matlab, so I don't even know if this is possible, but I...
  11. G

    Mathematica Can You Integrate a Function of Two Variables in Mathematica?

    I have a function of two variables F[x_,y_] and I Would like to integrate over one variable only and get a function G[x] for example and work with it. I want something like: G[x_]:=NIntegrate[F[x,y],{y,0,\infty}] But it doesn't work.
  12. G

    Mathematica Plot 3D in Mathematica: Getting Coordinates for Points

    I have a 3D Plot in Mathematica and I would like to get coordinates for points (all points) that were plotted.
  13. M

    Mathematica Mathematica: moving point creating a curve

    Dear all, here is my animation of a simple plot: Animate[ ParametricPlot[ {Sin[tf], Cos[tf]}, {tf, 0, t}, PlotStyle -> {{Thickness[0.002], Red}, {Thickness[0.002], Blue}}, PlotRange -> {{-2, 2}, {-2, 2}, {-2, 2}}, AspectRatio -> Automatic], {t, 0.01, 100, 0.01}, AnimationRate -> 2...
  14. J

    Mathematica How can I convert a matrix to a list in Mathematica?

    Hi everyone: I would like to join all elements of on matrix into just one list: matrix = 1 2 3 4 5 6 7 8 9 into list = {1,2,3,4,5,6,7,8,9} Anyone has a solution for this? Thanks
  15. H

    Mathematica Help with "Which[] in a For loop using Mathematica

    Hello, I am a novice in Mathematica, but insisting to learn it. I would appreciate help in solving the following problem: (*a=1;Which[a==1,x,a==2,b]*) list := List[1611, 1612, 1613, 1614, 1615, 1616, 1617, 1618, 32, 10] For[i = 1, i < 4, i++, a = list[[i]]; Print[a]...
  16. X

    MATLAB Matlab vs Mathematica for computing derivatives

    I'm trying to do a calculation which involves taking the derivative of a term that is millions of terms long. I'm using a supercomputer right now with Mathematica to do it but it's taking to long. Does Matlab have a faster algorithm for computing derivatives analytically?
  17. M

    Mathematica Using mathematica to reduce a system of n equations and m variables

    Hi guys, I have a system of six equations and thirteen variables. I would like to reduce it to seven free parameters. I used Reduce to solve it but it is taking really long (one full day and no output yet) and I think there must be a better way. Here is my code Y = {{y1}, {y2}, {y3}} T =...
  18. S

    Mathematica Mathematica - get value of function at certain x

    Hi, I am not really sure this is the right topic to post my question in, but it is homework so... To my data in txt file I fitted a function ##f(x)## where ##x\in [0,100]##. In the original file I had only 100 points, but now that I have a nice polynomial fit, I can get infinite number of...
  19. Safinaz

    Mathematica Finding the range of the paramter space in Mathematica

    If I have a function depends on for example 2 parameters f[a,b], and I know the value of this function should range between 300 < f < 400, how I know the possible ranges of the parameters in Mathematica. Bests, S.S.
  20. WannabeNewton

    Mathematica Solving ODEs with large parameters in Mathematica 9

    I have an ODE ##e^{2x}H(Hv'(x) + H'v' + Hv'') + (k^2 - 2e^{2x}H^2(1 + \frac{H'}{2H}))v = 0## where ##H(x)## is a known function that Mathematica has stored as an interpolation from a previous ODE and ##v(x)## is the unknown function to be solved for. ##k## is the adjustable parameter. Using...
  21. Hepth

    Mathematica [Mathematica] Bug in Integrate with derivatives of a delta function

    Integrate[f[qs] DiracDelta'[qs (1 - 1/x)], {qs, -\[Infinity], \[Infinity]}, Assumptions -> 0 < x < 1] Integrate[f[qs] DiracDelta'[qs - qs/x], {qs, -\[Infinity], \[Infinity]}, Assumptions -> 0 < x < 1] This is on Mathematica 8 for windows. The results differ by a sign. They are effective...
  22. N

    Mathematica Mathematica Plots Wrong: How is it Possible?

    I said to Mathematica to plot a graph as this: Plot[Exp[-Sqrt[-x]] + Exp[Sqrt[-x]] - 2 == 0, {x, -10, 40}]. You can see that there is square root of -x, which should mean that the function is defined only for x<=0. But no, Mathematica would plot a curve also for positive values of x. How...
  23. Hepth

    Mathematica [Mathematica] : Mathlink/Evaluation of a function using NMinValue/NMin

    I have a function that is defined using a variety of things, some matrix algebra, some mathlink functions, etc. But they are all defined to evaluate when called with the parameters : chi2[mb, vmc, v1, v2, v3, v4, 0.1066, 0.219] gives me a number back. I can even do a table over some range...
  24. N

    Mathematica FindFit doesn't work for me in Mathematica

    Hello, I want to fit a two-parameter function to two points in this way: FindFit[{{0, 1}, {1, 0}}, D + C *Log[-1 + Sqrt[-C^2 + (-1 + x)^2] + x], {C, D}, x] But Mathematica won't give the values for parameters C and D. Instead it says: "FindFit::nrlnum: "The function value {0...
  25. K

    Mathematica How to define functions with integer index in mathematica

    There is a vector ##v_i(t)## (i=1,2,3). How to define the three functions in Mathematica? What about ##t_{ij}(t,\vec{x})##? I am trying to solve my vector and tensor equtions with Mathematica. Analytical solution would be perfect but numerical solution would also be fine. Actually I am not...
  26. adjacent

    Mathematica [Mathematica] Number problem with digits

    Determine all three-digit number ,##N##, having the property that ##N## is divisible by 11, and ##\frac{N}{11}## is equal to the sum of the square of the digits of ##N##. This cannot be solved just by guessing. I think I should use mathematica for this,but, this sum of the digits is a scary...
  27. S

    Mathematica Mathematica being very strange

    So when i use the following command, I get the following error DSolve[y'[x] - y[x] == 3, y[x], x] DSolve::deqn: Equation or list of equations expected instead of False in the first argument False. >> But when i change the variable y[x] and y'[x] to s[x] and s'[x], It works why is this...
  28. E

    Mathematica Free alternative to Mathematica?

    In Mathematica, I computed the integral ##\lim\limits_{n\to\infty} \frac{1}{n^2} \int\limits_{0}^{\frac{\pi}{2}} \frac{\sin((2n+1)x)}{\sinh(x)} \ dx## and it incorrectly output the answer ##-\frac{3\pi}{2}##. I wanted to try a different CAS software that might provide a different answer, but so...
  29. M

    Mathematica Mathematica - How to make 3D plots flat

    Hello, I've been using mathematica the past few days and quite like it. I am trying to add some figures to my word document. Because of the size of the exported emf file from mathematica, I am unwilling to have a document that is 100MB in size. So I was searching for some ways to export...
  30. D

    Mathematica Collecting terms in mathematica

    I have an integrand with a handful of terms, and some of them have poles in the denominator of the form (x+c) (but not all). There are three poles in total, and I want to collect all the terms according to each pole individually (eg all the terms with (x-1) in the denominator, (x-5), etc.)...
  31. Rasalhague

    Mathematica Evaluating a derivative at a point in Mathematica

    If I define a function, such as f[x_, y_] := {-2 x + 2 x^2, -3 x + y + 3 x^2} I can compute the derivative with D[f[x, y], {{x, y}}] but what is the syntax for evaluating this derivative at a point?
  32. C

    Mathematica How Do I Handle Variables in Mathematica as a Beginner?

    Hello, I'm just testing out mathematica for the first time. I was hoping someone could help me make sense of this input (see attached screenshot). I'm sure I'll be running into more peculiarities as I get more comfortable with the software, Ill post them in this thread as the pop up. Help much...
  33. N

    Mathematica Mathematica calculates for ages

    Hello, I told Mathematica to do a few calculations as follows: a = 0; b = 1; n = 4; For[i = 0, i < n, i++, p = 2*x*b - 2*i*a; a = b; b = p] c = CoefficientList[p, x]; l = Length[c]; m = 0; For[i = 1, i < l + 1, i++, r = Abs[Part[c, i]]/Abs[Part[c, l]]...
  34. N

    Mathematica Defining a function in Mathematica

    Hello, I know that in Mathematica one can define a function as follows: f[x_]:=x^2. The problem is, I get a polynomial from a for loop as an expression p=a*x^n+b*x^(n-1)+... Now I want to evaluate the polynomial at a specific point. I tried to define a function from the polynomial as...
  35. S

    Mathematica How to get smaller-size eps figures from Wolfram mathematica?

    Dear every Mathematino-s in high energy physics I knew several workers in computer and mathematics, but few of them know wolfram mathematica software, so I think it is justified to let my question appear here. I use wolfram-mathematica to make 3D figures and want to use them...
  36. Hepth

    Mathematica Mathematica : Noncommutative Multiply and Replacement Rules

    Val[a_] := ToCharacterCode[ToString[a]][[1]]; GH[a].GH[b].GH[c].GH[d].GH[b] //. {GH[a_].GH[b_] :> If[Val[a] > Val[b], GH[b].GH[a], GH[a].GH[b]]} I have the noncommutative multiply of GH[a].GH[b].GH[c].GH[d].GH[b] My goal is to order these in increasing charcter value. (Val is the function...
  37. T

    Mathematica How to solve Solve x-2cosx=0 in mathematica

    Solve[x - 2 cos[x] == 0, {x}] this is my imput but i get an error. What is the command to solve trig functions in mathematica thanks. I searched online but no avail.
  38. N

    Mathematica Integrate vs. NIntegrate in Mathematica

    I'm trying to integrate the function Exp[-I*t*x - t^2/2] from -infinity to infinity using NIntegrate in Mathematica; the value that I get is accurate when x is small, but as x gets larger, the output from NIntegrate does not match the value I get when I use Integrate -- it gets less and less...
  39. G

    Mathematica Mathematica: f[a,b,c] = a*g[b,c], force evaluate

    Hey, Say I have a function f[a,b,c] which depends on another function g[b,c] such that: f[a,b,c] = a*g[b,c] If I input, f[a,1,2], mathematica spits out a*g[1,2] rather then actually evaluating what g[1,2] is. Is there a way I can force mathematica to evaluate g[1,2] so instead, e/g if g...
  40. Hepth

    Mathematica Mathematica : Integrate and a Log problem?

    Here is the code, I am using Mathematica 7 with no packages installed at the moment. $Assumptions = 0 < u <= 19/80 && I10 \[Element] Reals; FXN = Sqrt[(u - 15/16)^2 - 2/5 (u + 17/16) + 1/25] (I10 (u^2) - 1/u); PA = Integrate[FXN /. {I10 -> 1/2 Log[1/2]}, u]; PB = Integrate[FXN, u] /...
  41. kq6up

    Mathematica Mathematica vs. Other Math Apps

    I have been using Maxima to help me review to go back to grad school for physics. I think I might be running to the limits of its functionality (or maybe I just don't know how to use it correctly). I used to have a lot of experience with Mathematica, but their license system has grown to be...
  42. F

    Mathematica [Mathematica] FindFit/NonlinearModelFit with non-gaussian residuals

    Hi, I note that in the 'more info' for NonlinearModelFit it says that it assumes the values are normally distributed around the mean response function y, which I understand is required if one wants to use maximum likelihood methods and construct confidence intervals etc. However, there appears...
  43. C

    Mathematica Solving ODE numerically in Mathematica - 'ndnum' error?

    I'm trying to solve this ODE R'(t)=\frac{-a}{R(t)^2} numerically in Mathematica (a, b are non-zero constants). Here's what I have: NDSolve[{R'[t]==-a/R[t]^2, R[0]==b, WhenEvent[R[t]==0, end=t; "StopIntegration"]}, R, {t,0,1}] It's returning with NDSolve:::ndnum : Encountered...
  44. T

    Mathematica Inverting dispersion relation with Mathematica

    Hi guys, I'm currently working on a project related to Faraday instability, and I of course came across the dispersion relation for capillary-gravity waves, i.e. ω² = tanh(kh)(gk + σk³/ρ) . Now I would need to numerically solve this relation for the wavenumber k as a function of depth h...
  45. N

    Mathematica Tag × protected in Mathematica?

    Instead of giving the results of the calculation, Mathematica says: "Tag Times in 0 × 1.52098*10^11 is Protected." as in the attached file. Anyone has any idea how to get the results?
  46. Hepth

    Mathematica Mathematica : Easy? Function that returns and increases counter.

    I have a statement that looks like : vD.vD.vD.vD Where vD is noncommutative (but that doesn't really matter) I want to replace it so that each vD becomes v[a].D[a] But I would like it so the "a" is not repeating. So I need somehow a function that each time it is run returns it with...
  47. R

    Mathematica I have a problem with mathematica

    Hello,I need help in Mathematica,my problem is that I wrote the system of differential equations and I put a certain value of the variables and it is supposed that the value of the absolute of the determent would be zero but unfortunately I did not get zero , I got another answer when I put...
  48. M

    Mathematica Solve Error in Mathematica: Get Solution Here!

    Here is my code Nl = 10^(49) ; Nh = 100 ; b = 4*10^(-13) ; Rs = N[((3 Nl)/(4 Pi b Nh^2))^(1/3)]; a = 6*10^(-18) ; Solve[x/(4 Pi r^2) E^(-Nh a x) a Nl == (1 - x)^2 b Nh, x]When I run it, it shows the error: "Solve::nsmet: This system cannot be solved with the methods available to Solve. >>"...
  49. IridescentRain

    Mathematica How do I calculate an area in Mathematica?

    Hi! Say I have a region described by any number of inequalities. This region is a surface in 3D space. How can I ask Mathematica to calculate the region's area? If it helps, my particular region is the intersection of a hollow sphere and a solid (i.e. filled-out) toroid-like surface. I'm...
  50. Hepth

    Mathematica Mathematica : Pulling inputs from a function; methodology question.

    I have a heaviside function: HeavisideTheta[a,b,c,d,e,...] where the letters correspond to functions, and the number of functions is arbitrary. I want to make a replacement so that HeavisideTheta[a_]:> If[a>0,1,0] HeavisideTheta[a_,b_]:>If[a>0,1,0] If[b>0,1,0] or something similar. I wish...
Back
Top