# All Questions

179 views

Why does this work: Graphics[{Circle[{0, 0}, -Pi/4]}] But this doesn't? Graphics[{Circle[{0, 0}, N[-Pi/4]]}] Telling me: ...
34 views

### Plotting a parameterized vector in the x-y plane

I am trying to plot the trajectory of a parachutist descending at a constant vertical rate of 8 m/s while a south wind also blows at a rate of 8 m/s. He initially jumps from a height of 300 m. I am ...
57 views

### Comparing unit normal definition in calculus with FrenetSerretSystem

I'm trying to compare the unit normal definition in calculus texts (i.e., $\vec N=\vec T'/||\vec T'||$) where $\vec T$ is the unit tangent vector, with the unit normal vector returned by the ...
161 views

### DSolve documention on web differs greatly from distributed MMA 10.2.0 version

In the course of improving my answer to 95361, I noticed that the DSolve documentation on the web is much better written than that distributed with Mathematica ...
202 views

### Generate multiple integer variables with constant sum

I have asked similar question three day ago[The old question]. it was incorrectly marked as duplicated. This time I make this question more general and closer to reality. I want to build a model of N ...
66 views

### Lloyd relaxation on VoronoiMesh

How can we apply Lloyd's relaxation algorithm to a VoronoiMesh? Thanks. UPDATE Thanks a lot KennyColnago for your answer. Based on Simon Woods sugestion of using ...
146 views

### Trying to model a chemical reaction - NDSolve::litarg error

I am trying to model a chemical reaction with NDSolve. I have specified the known differential equations and parameters, ...
58 views

### Purchasing a laptop to fit Mathematica system requirements [closed]

I need to buy a new laptop and I intend to run the latest student edition of Mathematica (I am not sure if that is equivalent to Mathematica 10). What I don't understand are the specifications needed ...
79 views

### Plot Text Data in Mathematica

I am trying to analyze some text data for my thesis! How can I plot this data in Mathematica in a barplot based on the frequency of the words and combinations of them? On the Abscissa (...
91 views

### A bug in Rasterize?

I plot a straight diagonal line and then simply rasterize it. Consider what happens (Mathematica 10.2 on Windows 7 x64): ...
103 views

### How can I illustrate the solution space of these equations in 3D?

I would like to plot the solution space $\{\theta,\varphi,\Omega\}$ of this vector equation, \begin{pmatrix} \sin (\theta ) \sin (\varphi ) \sin (2 \pi \Omega )-\sin (2 \theta ) \cos (\varphi ) ...
122 views

### PixelValues along a straight Line [duplicate]

UPDATE to the question I have reformulated the question in order to make it distinct from the one suggested as a duplicate: "Line Intensity Profile From Image." The key difference is that I'm ...
51 views

### Program for fractional-order Lorenz system

Here, I am writing the Mathematica program for fractional-order Lorenz system by using Euler method. Please check the following code and correct it. Program: ...
36 views

### Filling option failing when used with ListLogLinearPlot

As mentioned in this question the following filling seems to work well. ...
16 views

### Using Solution of NSolve when Passing a Function Inside [closed]

I apologize if any of my questions are super easy, I am new to Mathematica. If I do something like this: f[x_] := 1/2 (3 x - x^3) a = NSolve[f == x, x] I will ...
42 views

### Solve 4 equations using Solve [closed]

I'm trying to solve $4$ systems of equations with $4$ unknowns. There are some trig involved and I keep getting error "Solve::ifun: inverse functions are being used by Solve." Please help me to ...
46 views

### HoldForm -> InputForm without processing the contents

I have programmatically generated a large number of simple equations like 1+1/2. I need them to be 'unprocessed', so they've been run through ...
36 views

### Why do notebooks reset themselves now and then? [closed]

Now and then I am working on a notebook and suddenly it reset itself. What I mean is that I am entering commands and when I type enter, the notebook command number goes to 1 and I have lost all ...
36 views

### Fourth derivative of a Bessel function [migrated]

I am given with a relation $$\frac{d^2}{dx^2}(P_l(x))=\frac{1}{2}\sum_{n=(0,1),2}^{l-2}(l-n)(l+n+1)(2n+1)P_n(x).$$ Using the above equation, I get ...
86 views

### Newton's Method Converges in Mathematica for non-convergent functions

In mathematica I set f[x_] := Sign[x] Sqrt[Abs[x]] and then I solved it in a root finding for Newton's method by doing ...
40 views

### ListPlot3D and plotting a 3 dimensional array [closed]

I have a 3D array of the form: {{{a1,a2,a3},{b1,b2,b3}...}}} and ListPlot3D only accepts data of form: ...
61 views

### Correlation suspiciously high [closed]

I used the Correlation function and got a value that seemed suspiciously high. The two series look like this when plotted: Correlation[fri1E, fri2E] // N ...
83 views

### Find subsequence A in sequence B A007908 - OEIS

I have sequence A as A007908 - OEIS and pattern B which is a sub-sequence of that sequence A. I need to find index of first occurrence of the given pattern. For example pattern ..1010... I've looked ...
69 views

### Turning table into association for Classify

I have the following sample data for 20 users. I know their sex, and the response for three yes/no questions. I am trying to building a classifier to guess their response to the third question, based ...
89 views

### Inverse of parametrized ellipse area

If you parametrize an ellipse (with the center, not a focus, at the origin) as: {a Cos[t], b Sin[t]} the area traced out from the focus (not origin) for a given ...
70 views

### Can I map a function over a sequence of arguments without making the arguments into a list first?

I would like to set evenFunction[f_][a_, b_, c_, ...] = f[Abs[a], Abs[b], Abs[c], ...] I have come up with two ways to do this so far. Use pure functions ...
94 views

### DSolve gives an empty solution set to a solvable ODE

I really hope this isn't a duplicate, today I was answering this question and was to lazy to solve the quadratic equation on my own and so just asked mathematica to give me the solution of the ...
44 views

### Fail to Create a package [closed]

This is rather basic. In an empty notebook I type in a single cell ...
52 views

### Call an executable

I have one data file, one executable file and one *.txt with the results from running the executable, all within the same folder. The folder has the path C : \ Users \ Dimitris \ Desktop \C32EXE ...
32 views

### How to prevent space trimming when importing HTML with ImportString?

I am importing a HTML-formatted string with ImportString[string, "HTML"] to properly parse all HTML-escaped characters like ...
163 views

### Consecutive identical integer members of a list

Can you help me to find and count sub-sequences of consecutive, identical integer members of a long list (at least 1000 members)? By sub-sequences I mean runs like ...
40 views

### Launch Front End from .NET MathKernel and return result to .NET

Is it possible to launch a front end and open a notebook from a .NETLink kernel and return a result from the notebook to .NET? In the code below "x" appears in the .NET textbox after 10 seconds but ...
206 views

### A tricky algebraic simplification

EDIT from the OP: Please delete this question. The whole problem was that I was using a very old version of MMa on a friend's computer without realizing it. FullSimplify[] handles it perfectly even ...
47 views

### Ctrl + Shift + 6 produces some weird symbol instead of power

I'm trying to configure the Ctrl+^ shortcut to produce Superscript instead of Power as described here, but for some reason I ...
53 views

### Mathematica computes too slowly at the start of a session [closed]

Everyone, I'm a Mathematica new user. I find it a problem that, when I start a new Mathematica session, it executes too slowly for the first command (say, "1+1", it may take a few seconds before it ...
302 views

### Plotting a Bifurcation diagram

I have the following system equation v'(t)=2*G*J1[v(t-τ)]cos(w*τ)-v(t) How do you plot the bifurcation diagram, τ in the x ...
460 views

### Defining indefinitely many functions

Is it possible to define a class of indefinitely many functions f1, f2, f3, ... such that ...
46 views

### How to generate a Log BarLegend for a DensityHistogram

I have a Log count histogram: DensityHistogram[myData, 100, {"Log", "Count"}, ColorFunction -> "Rainbow", ChartLegends -> Automatic] But ...
57 views

### Factoring out a common term

Very simple question, but I can't find a simple answer here or in the documentation. I have an expression: qq = a x + b x^2 + c x^3 and wish to factor out a ...
60 views

### How to use the variables from Table in calculation

New to the site and Mathematica. I'm trying to use the finite element method to get a temperature profile. So if $q_0=f(T_0,T_1)$, $q_n=f(T_{n-1},T_n)$ and we also know that ...
64 views

### Problem with DiscreteWaveletTransform for DaubechiesWavelet

I am trying to use Mathematica's wavelet transform. In preparation I entered: ...
72 views

### Select from a list using another list of limits

Given a list of values list1 = {2.4, 3.4, 5.9, 1.2, 9.5, 7.5} and a another list containing theoretical maximum values ...
49 views

### Solution to Simultaneous Arithmetic/Geometric Mean Recursion Relations

I'm trying to solve the simultaneous convergent sequences of geometric/arithmetic means where $a_{n+1}=\frac{1}{2}(a_n+b_n)$ and $b_{n+1}=\sqrt{a_nb_n}$ and initial values are $a_0=1+x$ and $b_0=1-x$. ...
68 views

### is this a possible integration bug? [closed]

I am find a discrepancy in evaluating an integral which has given me trouble all day. I have finally isolated where the problem is which I now frame: I define the integral in terms of a delayed ...
73 views

### Importing and saving .csv files as variables with the original filebasenames

I have a modest number of .csv files that I want to import into mathematica. I would like to save their contents as their filebasename for use throughout my notebook, but I am running into errors as ...
56 views

### Ploting a parallel graph for an animation

I am sorry that my attempt to obtain a fully functional plot as I want failed badly because I am not able to integrate the features to the graph. Here is my simple code: ...
60 views

### Mathematica applies the replacement rule without telling it explicitly? [closed]

I ask this question just because of curiosity. Consider the following code with a replacement rule defined in its begining: ...
100 views

### Alternatives to Span? [closed]

Is there a better alternative than Span for getting particular columns out of matrix. For example, if I have the data: {{a,b,c},{d,e,f},{g,h,i},{j,k,l}} and I ...