All Questions

5 views

ParametricPlot two Piecewise functions

I am trying to ParametricPlot two Piecewise functions. Here are my two Piecewise functions: ...
10 views

How can I set an axes scale on x in terms of Pi?

If I plot a function just like that Plot[Sin(x), {x, 0, 3Pi}] I'll Get a plot whit the x betwenn 0 and 10, I'll like to know how can I could modufy the x axes ...
6 views

Debugging NDSolve to see numerical values at each time-step

I wish to debug my NDSolve function and this is my first time using the Mathematica debugger. I have read around and attempted various different ways of debugging but I cannot figure it out. I want to ...
11 views

How to use vector plot and gradient vectors?

How do I plot a sampling of gradient vectors for fby using the vectorplot command? I’m confused how to use both these commands.
18 views

Multidimensional Matlab conversion

I try to convert this code Matlab code: ...
16 views

Custom Property interface on my own objects

I know I can use the Property interface for things like Graph but I want to use it for all of my objects. This includes: ...
13 views

Shading between two regions of two separate parametric curves/function

I have two long functions g12 and g14 in terms of g2: ...
50 views

How can I order this list on mathematica?

This is my list Matrix = {{1, -2, 3, -4}, {{a, b}, {f, e}, {a, b}, {f, e}}} I want to order the columns in ascending order depending on the values on the first ...
22 views

Finding all roots of a function within an interval

I have the following code: ...
17 views

Problem with building graphic using ListPlot

I want to build the graphic using ListPlot but it doesn't work. I get list in next form: ...
20 views

Understanding conditional expressions returned from definite integral

I dont understand how to interpret C[i] returned from a definite integral when there are no C[i] terms in the actual answer, only in the conditional expr. Thanks! Dan
20 views

Plotting points with different marker and different plotlegend

Currently i'm stuck at problem, where i have a sets of points, and I wish to plot these point with different plot markers, and also with different plot legend. The code is the following: ...
13 views

RunProcess returns a confusing error message when using ProcessDirectory options

Here is one way to find the names of the files in one's home directory: FileNames["*", "~"] (* { "~/.account", "~/Applications", "~/.bash_sessions", ... } *) ...
34 views

How to solve the system of two equations to get the approximation value

I'm a Ph.D. student in Banking and Finance and I'm not familiar with the solving system of equations. I don't know how to solve the two equations below to get the approximation value of x, and y. All ...
17 views

Command line arguments to wolframscript interact strangely with -file option

In order to avoid script-defined command-line arguments clashing with existing arguments to wolframscript, it appears you are supposed to use the ...
28 views

Solve second order differential equation with boundary values

I'm a bit new to solving differential equations in Mathematica. I want to solve the differential equation for f(R): Eq = f''[R] + K2[R]*f[R] (*=0*) With the ...
37 views

Easy way of integrating the same integrand over several intervals?

I was wondering if there is some shorthand in Mathematica for expressions such as $$\left(\int_A + \int_B + \int_C + \cdots\right)F(x_1,\ldots, x_n) dx_1\cdots dx_n$$ where $A,B,C,\ldots$ each ...
50 views

Can this integral be calculated using Mathematica?

I have the following integral:  \int_{-\infty}^{\infty} \frac{\mathrm d\tau}{2\pi \mathrm i} \int_{-\infty}^{\infty} \frac{\mathrm d\tau'}{2\pi \mathrm i} \frac{\mathrm e^{-c^2(\tau - \tau')^2}}{(\...
34 views

Manipulate does not work with random and text display

I would like to do a small demonstration of Monte Carlo integration. However, When I generated the plot code, it does not work properly. ...
21 views

Invert color in MatrixPlot

How can I invert the grayscale colors when using MatrixPlot? My data is between 0 and 1 and the color scheme when using GrayLevel...
19 views

InputField enabled or disabled with two dynamic variables

Dynamic has been really useful for me but it is as well not easy to understand also. I am doing a calculation where I want some of the input fields enabled or disabled depending on where I am in the ...
66 views

Interactive Labeling of Images

I have a list of pictures: pictures = {im1,im2,im3,im4,im5,im6} Where im1: im2: im3: im4: im5: im6: I want to assign the pictures to labels (1,2,3,4,5 ...
41 views

Unable to use Solve to solve simultaneous equations, or use Maximize for exact maximum solution

Mathematica has found that the maximum of the following function is negative using NMaximize, but I am trying to prove that the maximum is negative (i.e. that the ...
280 views

Deleting duplicates only if they are a certain kind of duplicate

I have a list of tuples like this: {{1,a,b},{1,1,b},{1,a,a},{b,a,1},{b,a,b}} I would like to find a way to delete all those tuples in the list that contain a ...
63 views

Solve or Reduce don't work with Integer functions

I had been trying to limit for some c++ programs, the bigest whole number they can handle is lim = 18446744073709551615 and the different functions are: ...
46 views

Problem using Nonlinearfit on integral function

I tried to fit my data with a very complicate Integrated function. But I get many errors messages when I perform the fit. For exemple I get : NIntegrate::inumr: The integrand ....has evaluated to ...
20 views

Table of SystemModelSimulate Data

I am trying to simulate a model in SystemModeler from Mathematica 11.3. I wish to simulate this model for various parameter values and make a table of the output data. To attempt this I do the ...
36 views

Solved: Randomizing Initial Conditions of NDSolve Differential Equation Phase Space Plots with Looping Structures

I am looking for a way to randomize the initial conditions on the numerical approximation for the angular displacement of a plane pendulum. I have been trying for hours, and believe a For loop is ...
45 views

Changing the values of variables throughout a notebook

I have a model with many parameters, and I'd like to see how the model changes when some of those parameters change. Right now many of those parameters are set to prescribed values, i.e., ...
37 views

Why is my GroebnerBasis = 0 in this case?

I recently asked a question: Finding Intersections Between Arbitrary Surface and A Line whose solution required me to use the GroebnerBasis function. I successfully ...
98 views

How do we cluster separate curves in a set of data?

Below, I have included some data. (It is long, but I don't like to host data elsewhere and provide links that might some day be broken.) Plotting this set of data,...
37 views

Representing an interpolating function

I just want to figure out how to "represent" or to inject an interpolating function into a numerical calculation. So, suppose i have an interpolating function $int$ and then i want to use NDSolve or ...
50 views

Manipulation of 3D matrix

Assume that we have a 3D array x, and we would like to split it into 2D slices then cut every slice into some small patches and get all patches in single list ...
32 views

Find minimum precision setting

I am using FindMinimum command to find a local minimum of an object function. My code is below ...
45 views

Assume a variable is a Matrix

Is it possible to tell Mathematica to assume a variable is a matrix, analogous to assuming a variable is real with the Assuming command?
24 views

How put a matrix in a row (with or without index titles) using mathematica

I am trying to put a 16x16 complex matrix in a row, with separated columns to real and imaginary parts (i.e a 1x512 matrix). Additionally this 16x16 matrix is generated by an operator ...
53 views

How to run a CellularAutomaton until a configuration is repeated?

I would like to do something like CellularAutomaton[10, {1, 0, 0, 0, 0}, 2^5], but instead of running for 2^5, it should stop as ...
28 views

Not getting solution to simple equation [on hold]

qThis is my code. R = 12.17 g = 9.8 θ = 36 Degree Solve[R==v*cos[θ]*(v*sin[θ]+sqrt[(v*sin[θ])^\.1d2 \[Minus] 2*g]), v]` What is the problem with this code?
115 views

Transferring DownValues

I have a code in which I define something like this: cc[1, 2] = 1; cc[2, 6] = 12; cc[3, 7] = 3; After some manipulation I define a sort of temporary variable ...
58 views

Is there a way to automate this procedure?

I have some code which numerically solves a differential equation for a given value of the parameter $M0$ and for some initial conditions. The initial conditions will remain fixed throughout the ...
82 views

Convert Unicode to Math Input

Any Ideas how I could convert unicode to Mathematica Input ? For instance : I have the following Unicode: test= {"a", "\\:1d62"} So here I would like to convert ...
53 views

Deleting sub-list that contains duplicates

I have a large list of uniform-length lists. What is an efficient way to delete component lists that contain duplicates? For three-item sub-lists, I have used the following code: ...
83 views

How to make a frustum of a cone

For finite element purposes I need a frustum of a cone with a finite wall thickness, i.e. a tapered pipe. To make a cone is easy ...
45 views

Series expansion of a multi-variable function with singularities

Can anyone help me to find the series expansion as a polynomial of the following multi-variable function with singularities? f[x_, t_] := 1/(x - t)^(1/4) Where <...
47 views

How can I better formulate a conditional statement?

To solve optimization problems I have seen this: Is there a more elegant way to do this with alternative conditional expressions? Is there something equivelant to ...
25 views

Solving a Volterra integral Equation with singularities

Dears, I am trying to solve the equation in the below picture. What I did is: I used wavelet functions and substitute the wavelet instead of u, where I have the ...
86 views

Unexpected behaviour of PowerSpectralDensity

I recently wanted to calculate the power spectral density of a surface profile. I was happy to find out that there is a built in PowerSpectralDensity[] function in Mathematica (version 10). However, I'...
54 views

Create a cross-section, time series data set using Matrix operations

I have developed the following code, which produces what I aim to obtain. ...