# All Questions

0answers
33 views

### How to solve two non-linear equation simultaneously? [closed]

I want to solve two non-linear equation at same time with some condition, the complete description of the problem is attached, any comments? Thanks
0answers
57 views

### Academic citations network [closed]

Do you know if there is curated data that generates a network of academic citations? Something like http://well-formed.eigenfactor.org/radial.html or http://www.eigenfactor.org/map/maps.php I could ...
1answer
30 views

### NDSolve with arrays and Tables of Equations and WhenEvent

I've been toying around with NDSolve for a while, and read through the website. By doing so I discovered that I could use it for vectors and arrays with much pleasure. So I wanted to write a simple ...
2answers
62 views

### Placing some controls above and some below plot

The code below is something I wrote quickly to simulate the problem I'm having with more complex code. I use Row (or Grid) to get the first 2 manipulate variables (a and b) on one line above the plot ...
3answers
115 views

### Generating a list of questions (simultaneous equations)

I am trying to create a list of simultaneous equations showing steps, where I only need to change a, b and the question number, and maybe a couple of minor things about q (where q is the factored ...
3answers
125 views

### Plot parametric solutions using Manipulate [duplicate]

I want to plot the parametric diagram of {y[t],z[t]}, in which I manipulate a parameter, ω, from $[1, 10 \pi]$. Here is what I have attempted, but I can't get a ...
0answers
44 views

### Multiple NIntegral with singularity

I need to compute the following integral FF[0]. When evaluating FF[0] Mathematica simply takes too much time. The problem may ...
0answers
52 views

### Open a Mathematica 9 notebook in Mathematica 8

I have the following question: Can I open a Mathematica 9 notebook in Mathematica 8? Are there compatibility issues?
2answers
308 views

### How to visualize slope fields of differential equations without vectors?

I'm looking to visualize slope fields of differential equations for my differential equations course. Every example I see draws them as vectors, adding unnecessary "arrows" that, to me, are visually ...
2answers
24 views

### Combine two functions in mathematica to get one image with two elements

I am trying combine this two functions into one piece in grid. ...
3answers
135 views

### Colorize a 3D distribution of points according to density

Suppose we have some random 3D distribution of points. I'll use the spherical ball defined below as an example and a starting point for the discussion here : ...
1answer
41 views

### Simplify rearranges equations?

I've been using Simplify/FullSimplify to simplify some nasty equations, and by and large it does well but sometimes it rearranges equations in an unhelpful way. ...
0answers
100 views

### A* algorithm for finding shortest path in a graph

FindShortestPath finds the shortest path between two vertices in an edge-weighted graph, allowing a choice between the Dijkstra and Bellman-Ford algorithms. In my (limited) understanding, both of ...
0answers
71 views

### How to increase processing speed? [closed]

Well, let's first begin with the specs of my computer: Win 8 i7-3537U CPU@2.00GHz 2.50GHz 4GB of RAM 64-Bit And using Mathematica 8 I have to create some programmes to solve statistical problems, and ...
1answer
46 views

### Can I make a function which depends on several arguments which are not independent?

Here's a simple example Suppose have the permanent relation that z is proportional to xy^2, for real numbers s. z = s x y^2 Now, we are interested in ...
1answer
73 views

### Initial and boundary value errors

NDSolve::ivone: Boundary values may only be specified for one independent variable. Initial values may only be specified at one value of the other independent variable. >> I keep getting this, ...
2answers
51 views

### How to divide a notebook into sections? [closed]

I've seen some very nicely formatted Mathematica notebooks with sections, explanatory text, etc., but I can't figure out how to do something similar. The documentation is not especially helpful here ...
1answer
43 views

### Make duplicate string then join two strings together in a table

I have two lists of data, dataA and dataB. ...
0answers
57 views

### How to save the output file and make it run without mathematica? [closed]

I want to save a file, as the picture shows, and make it run without mathematica. I have to move this file to another computer which dose not install mathematica and run this file with all functions, ...
2answers
45 views

Let be given the complex number $z$ satisfying the condition $|z-2+2i|=2\sqrt{2}$. I want to find the complex numbers $z$ so that their modul obtain least and greatest value. I tried. Put z = x + y ... 2answers 121 views ### TrackedSymbols affected by CurrentValue. Another problem with SetDelayed(:=)+OwnVales in Initialization It is MWE, only a Disk[] that should print "Click" when clicked. Also "date... updating" ... 1answer 31 views ### Summation for a function having singularity I need to do summation of this function with Mathematica. For[t=0,t<500,t++;Sum[-Q*Log[Q],{k,-Infinity,Infinity},{n,-Infinity,Infinity}]] Q= Q1+Q2+Q3 where ... 0answers 109 views ### Every third element in a list [closed] EDIT - Just wanted to change wording Okay, so I didn't find an exact answer to this online so here I am. I have a range of integers from 1-200 ... 0answers 26 views ### Problem with slot in If statement [duplicate] I am struggling with slots, In this case I have a function int which gives either true or false. When it gives true, I want ... 1answer 58 views ### How to Solve/NSolve/Reduce this rationalized equation In this problem I don't know why the system is not solvable. I have just one unknown K0. ... 1answer 43 views ### Extracting second value of each sublist [duplicate] How can one get the second value of every array inside the outside array? I have the following data data = {{10, 20}, {30, 40}, {50, 60}}; I want to extract ... 0answers 31 views ### Changing the tick marks on the y-axis [closed] I know that Ticks allows me to scale the x-axis in terms of pi for example. How would I do so for the y-axis? EDIT: I've just realised how to do so: Plot[Sin[x], {x,0,10} , Ticks -> {Automatic, ... 1answer 77 views ### Extracting Imported Information What I want to do is to compare the relationship between the consumption of say beer and wine using scatter plots where each point designates the particular country (preferably named). I have tried to ... 0answers 80 views ### Fourier transformation of HeavisideTheta functions I want to find 2D-Fourier transformation of the function given below f = HeavisideTheta[y1]*HeavisideTheta[y2 - y1] For the purpose, I use built-in function in ... 2answers 102 views ### Permutations with restrictions I have a problem that can be modeled as: there are 8 boxes in total, and 60 different items. I want to put all items into boxes (all of them can be put into a single box). Now I want to find: 1) ... 1answer 44 views ### Choose partition of a set with Manipulate Suppose I have a set represented by an array of strings, like set = { "A", "B", "C", "D", "E", "F" } I would like to create a Manipulate which allows the user to build repartitions of the set. ... 1answer 36 views ### ContourListPlot not evaluating all of interpolated area I am trying to plot a contour for a matrix, but it seems not to be evaluating all the points. Here is the interpolated figure, followed by the MatrixPlot version itself. I used this colormap because ... 1answer 32 views ### Slow evaluation of complicated Table I have a system of recursive equations x[t+1]:=f[x[t],p[t-1],a[t],a[t-1]]; p[t+1]:=g[p[t],x[t-1],a[t],a[t-1]]; a[t+1]:=h[x[t],p[t],a[t],a[t-1]]; I want to ... 2answers 154 views ### extract line from position data I got a picture like this, and what I want to do is to extract lines from the picture. what I have done now is ... 1answer 76 views ### How to handle keyboard events for unselected item in CDF? How can I force the keyboard input to work for this cell without clicking on it after I evaluate or showing a blinking selection cursor? This is for running CDF games in a browser. ... 0answers 74 views ### Using NVIDIA 3D Shutter Glasses with Mathematica Mathematica has great capabilities to display 3D Graphics rendered to the 2D screen. This should make it perfectly suited to use the Graphics3D system together with an NVIDIA Graphics card, a 3D ... 0answers 50 views ### Constructing lists of evaluated functions inside Module [closed] This is my code: ... 0answers 60 views ### Playing around with “spherical k-ellispe” on the sphere surface [closed] It the Spherical K-ellipse I am looking for. What I mean is something like this but just with the two red curve and the sphere, idealy play with 2 parameters(number of foci and angle of the cone ... 0answers 43 views ### Solving for a variable within a definite integral using FindRoot I want to solve for P in this equation: Integrate[1/((P/(M*V)) - r*g - c*A*(V^2)*p/(2 M)), {V, 0, 26.82}] = s , where all constants are given except P. I've ... 1answer 66 views ### RandomSample Bug? I was using RandomSample with very skewed weights. I am asking for a random sample of 6 numbers 1 through 100 without replacement. In the screen shown, the weights for 1 through 6 are 100 000, with ... 0answers 39 views ### Type Vietnamese in Mathematica I type Vietnamese using UTF-8 Encoding but Text Display got error. How to type Vietnamese, Chinese in Mathematica. Please help me. 1answer 45 views ### Optimise CPU-intensive list combining function I have a list of numbers list1 from which I want to create another list (list2) consisting of only those numbers that are equal ... 0answers 21 views ### Set Image Size and Page Orientation When Exporting to PDF I want to export my plots (plot1 and plot2) as a pdf file. Since plot1 contains 4 figures in matrix form, so it will not fit in one page. ... 2answers 58 views ### Integrating a Simple Piecewise Function If I define f[x_]:=If[x<0,-1,1] and then integrate,say Integrate[f[x],{x,-3,7}] I get what I expect, namely 4. But ... 3answers 94 views ### Gather lists according to another list I have a first list of pairs like this one: ... 1answer 63 views ### How to plot a decahedron with Mathematica? I wrote Graphics3D[{Opacity[.9], FaceForm[Yellow], PolyhedronData["Dipyramid", "Faces"]}] and I get this picture: I would like to plot a decahedron without ... 0answers 42 views ### Why has my syntax coloring changed? Local variables in Module are no longer specially colored for me, but other syntax coloring remains, for example iterators in a ... 1answer 35 views ### Find the coefficients of a set of expressions in partial-derivatives [closed] Is there a way to find the coefficients of these (terms within the square brackets) expressions using mathematica? \begin{align} \hat{l}^2=&\sum\limits_{a=1}^{4}\left[\left(\frac{\partial ... 0answers 22 views ### Derivative with respect to certain variable. [closed] How would anyone calculate this derivative using mathmatica?? More specific with respect to dln(alfa) 0answers 30 views ### Generating the set of all three-dimensional binary arrays distinct under rotation and reflection? How can I automatically generate all possible three-dimensional binary arrays of size(x_1 \times x_2 \times x_3\$) where each array is distinct from all others with respect to rotation and reflection ...

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