# All Questions

131 views

### Format Preservation of FullSimplify on Indexed System of Autonomous Equations

I currently have a large system autonomous differential equations. I've indexed a more managable dummy system of identical form, using Part to reference each ...
112 views

### Anti-aliasing won't work when there is PlotStyle command

I've found that if there is PlotStyle command in the input, anti-aliasing will not work. However if the Style code is ...
231 views

### Output precision

I've solved some equations using FindRoot and then computed some values. Now when I print the output, I only get a certain precision {{0.01, 496.983, 61.3147, ...
380 views

### Import large amount of data with time stamps

I have a large data file (150 000 lines) which I want to import in Mathematica. The first few lines look like this ...
1k views

### large matrix eigenvalue problem

I need solve a very large complex matrix (not sparse and not symmetry) eigenvalue problem, e.g., 1e4*1e4 or even 1e6*1e6. How large dimensions of the matrix can Mathematica support? And, how about ...
633 views

### Sqrt — how to get negative branch?

One of the many attractions of Mathematica is that integers are generally treated as exact symbolic entities, and not just as numbers. I was just playing with Sqrt, and was puzzled by what appeared to ...
922 views

### Plotting a complex function [duplicate]

What does it mean if this message appears: {Im[(1-E^Times[<<3>>] f)/(1-Power[<<2>>] f)]-0,Im[(1-E^Times[<<3>>] f)/(1-Power[<<2>>] f)]-0} must be a list of equalities or ...
507 views

### How to guess initial complex value for FindRoot

I have to solve a transcendental equation for a parameter, say $\beta$. Now, the $\beta$ has a range from $ik$ to $k$ where $i$ is the usual imaginary root $\sqrt{-1}$ and $k$ is a real number. ...
102 views

### Plotting data that lands on the axis

I have a data point that lands right on the Y axis, which corresponds to the index of refraction of some sample. the x axis is the mole fraction of chloroform of my samples. How do I get the first ...
527 views

### ListPointPlot3D seen from above

I have a couple of {x,y,z} points a = {{0, 1, 0.}, {50, 1, 0.018931}, {100, 1, 0.02}, {0, 2, 0.}, {50, 2, 0.131}, {100, 2, 0.2}}; and I'm visualizing them with ...
122 views

### Only perform a symbolic differentiation once

I want to define a function that involves a differentiation step that Mathematica can do easily, which might be of the form ...
619 views

### Running a Numerical Simulation on a System of Differential Equations with unique initial conditions

I have a system of differential equations as follows: ...
230 views

### Problem with large values in ParametricPlot

I've got a question quite similar to No 18163:Problem with high parameter values in ParametricPlot, but the solution of that problem did not work for me. So I hope you may have another tip. I want to ...
225 views

### Separate an array in two arrays, the even and odd terms being separated in these two arrays

How can I separate the odd terms in one array and the even terms in another array,i.e., go from a={1,2,3,4} to aeven={2,4} ...
616 views

### Why doesn't my Manipulate work?

I am new to Mathematica and reading my way through a few books. Playing around with Manipulate and I noticed the following does not work: ...
244 views

### Thread over a nested list top to bottom until non-list elements are found

I have a nested list: list = {1, 2, {3, 4}, f[a], {2, h[b]}} I would like to apply a function g to all elements of the ...
104 views

### TextCell going awry due to ImageResolution (in Mathematica 7)

Can anyone see how to fix this text display? The example is from a larger project. I need to export the graphic at high resolution, but the text is going wrong. ...
1k views

### How can I get a Taylor expansion of the Sin[x] function?

How can I get a Taylor expansion of the Sin[x] function by the power series?
152 views

### How to take input from user?

Since I'm new to Mathematica I want to have a Notebook which takes inputs from user and returns average of the inputs entered and plots it on x-y coordinate. How can I do this?
587 views

### How do I make my discrete plot thicker?

I am making a discrete plot and a regular function plot together. But my curve is so thick that for color-blind people, it's pretty much impossible to see the black dots of my discrete plot: ...
504 views

### How to solve this integral

I'm trying to deal with this article, but I don't understand how equations 5.9 and 5.10 were obtained. I tried to use Mathematica 8 to solve it, but the answer was different. I have a problem with ...
445 views

### Why is Euler's number an uppercase “E” and not a lowercase “e”?

Why is Euler's number an uppercase "E" and not a lowercase "e"? Isn't Euler's Number normally expressed with a lowercase "e"?
386 views

### solving for one solution to a system of polynomials

I'm trying to solve a system of equations: ...
4k views

### How to plot imaginary part of a function

I need to plot the cube root of x in mathematica, but the plot shows me only the real part. I want it to look like wolframalpha plot with both real and imaginary parts of the function. Is it possible ...
112 views

### is there an equivalent of “show” steps? [duplicate]

Possible Duplicate: Get a “step by step” evaluation in Mathematica In wolfram alpha, when preforming for complicated integrals there's a 'show steps' option that explains how ...
51 views

### Solving differential equation (Analytical or Numerical)

I want to solve the following differential equation for $0 < x < 1$ ...
74 views

### Bifurcation diagram for iterative map [duplicate]

I have a mapping function (cubic logistic map) f(x)=rx(1-x^2) and I need to make multiple bifurcation diagrams, showing stable equilibria and periodic orbits for 400 equally spaced r values ...
57 views

### Permutation with a condition [duplicate]

I need to create a set A={“a”, “b”, “c”, “d” “e”} and print all the permutations of the set with lenght 3 that satisfy the condition:element "a" has to be ahead of "c" and "d" has to occur atleas ...
68 views

### How can I put the results of TrigFactor function into a more convenient form?

a1 D11 Cos[n x] + a0 a1 D11 Cos[n x] + 1/2 a1 a3 D11 Cos[n x] + 1/2 a2 a4 D11 Cos[n x] I have a large trigonometric expression. Can I factor out different ...
41 views

### How to add a positive definiteness of a unsymmetric matrix as a constraint to a Findminimum problem

The problem is I have a function which has 33 variables, and which to minimize it in a given set of contraints. I have also a matrix consisting of these 33 variables. The condition is that this matrix ...
156 views

### Projectile motion in Mathematica using Euler's method [duplicate]

I need to write the equations of a ball in projectile motion (ignoring air friction) with an initial velocity of 40 m/s at an angle of 40° with respect to the horizontal. Specifically, I need to ...
88 views

### How to plot and visualize a single linear vector in 3D? [closed]

I have a vector (in physic) designated as F1=250cos(60)i+250cos(60)j+250cos(45)k, and i would like to see it in a 3D graphic with the axis centered at the origin, after what i would include other ...
148 views

### How to construct a linear feedback shift register

Are there any posts regarding the construction of a LFSR (Linear Feedback Shift Register) in Mathematica? I can't seem to find any and I am not sure how I would construct one.
68 views

### Determination of Ricci tensor and Scalar curvature from veirbeins

Consider the following metric: $ds^2=h(r)\bigg(dr^2+r^2\big(d\theta^2+\sin^2\theta ~d\phi^2+(d\psi+\cos\theta ~d\phi)^2\big)\bigg)$ We can try to compute the Ricci scalar of this metric by using ...
120 views

### Non linear model fit

I need to fit this, but for some reason I cannot... data = {{0.617,0.8}, {0.605,0.6}, {0.5997,0.4}, {0.5972,0.2}, {0.5985,0.1}}; soln = NonlinearModelFit[data, {y - 2478.82*wlog[kc + 1]}, {y,w,k}, ...
108 views

### Estimating Parameters of a Custom Distribution

The problem is I can not get estimation of parameters of any custom probability distribution (distributions are not built in Mathematica), here is an example: First: I entered random numbers of ...
171 views

### Generate Matlab figure

I am currently working on a project. Because of lack of communication between my team mates and I, I did most of the work (and the graphical figures) in mathematica. Now, I have to pass all the ...
73 views

### Get all variables in an expression with Variables[]

"\[Phi]" <> "1"; Variables[%] Exp["\[Phi]" <> "1"]; Variables[%] Exp[Subscript[\[Phi], 1]]; Variables[%] Say I have lots of variables used for ...
127 views

### Suppressing reduction in fraction box size in multi-level fractions [duplicate]

Mathematica display complex fractions like this, the second x look smaller, I want it look like this, how can I get it in Mathematica?
273 views

### Show Progressbar after pressing a button

I've recently struggling with Buttons. So I understand Buttons have the form Button["text",action]. Now I want the action to be ...
140 views

### How to solve this nonlinear 2 by 2 equations?

I have a equation (x^2 + q1^2 - y^2)/2*(x + q1 - y) + (1 - 2*a)*q + 2*F = 2*(1 - a)*c[q] in q(variable) with parameters q1,a,F and function c(in variable q also, and I define it outside Solve so I can ...
180 views

### Why is 1. x (Times[1., x]) not simplified to x?

This is maybe a silly question, but I could not think of any logical reason why it is not simplified automatically. I was working with a big linear equation system with some constrained inequalities ...
344 views

### How to use FindRoot` to solve an equation containing a parameter?

I'm trying to derive some of the results of the following paper: Electrodynamics of semiconductor-coated noble metal nanoshells, JT Manassah - Physical Review A In the paper there is matrix \$\mathbf ...
91 views

### Why does Fourier give a large error in MachinePrecision?

Consider this code: ...
40 views

### save all inputs as list [duplicate]

I received three results of calculations: {k->0.190729} {k->0.197575} {k->0.249319} Could you help me write the results in the following form: ...
175 views

### Fraction of fibers that have failed

I have the following to set into mathematica. Assume a stress(sigma) applied on a specimen which has a number of fibers within it. All fibers that have a strength less than the applied stress should ...
78 views

### nested series expansion

I have to invert the following matrix in which the functions U[t,x,y,r] and K[t,x,y,r] and all their derivatives are "small"; ...
124 views

### A problem with set values

The following code is just an example to clearly explain my problem. Assume that : ...