# All Questions

135 views

### Moving a locator based on the movement of another

My problem is: I want two Locators to simulate a vector in the following sense: The first Locator is the base and the second ...
427 views

### Color of a plane in Contourplot3D

I have the following code example: ...
197 views

### Interpolating a sparse list of two-dimensional coordinates

I've run into a problem where I have an ordered array of sets of coordinates, for example: ...
683 views

### A rotation-like transform on a matrix

Do not be confused with comments, those are for previous version of the question - Kuba Imagine I have a matrix of the form: ...
1k views

### Units, plotting and empty plots

maybe I'm completely newbie but I can't understand the behavior of units and the command plot. I'm doing some easy plotting of the state equation for gasses: ...
156 views

### Issue with scope of variables

For the definitions, t = 1; f[x_, y_] := t (x + y); v[3] := {1, 1}; g[u_] := f[v[u][[1]], v[u][[2]]]; the following two expressions yield different results, ...
491 views

### RecurrenceTable with a recurrence function of two variables

I have to calculate the cool down process of a regenerative heat exchanger. I solved the problem in Excel before, but now I want to do it with Mathematica. I want to create a table with the variables ...
279 views

### Equating two lists, element by element

Say you have two lists: listA = {a, b, c} listB = {d, e, f} How would you produce a listC that equates each of the two's ...
319 views

### How to configure two Mathematica in different places with different settings

For some reasons, I should use two language versions Mathematica. The most reason is I want to see the comparison of Help page(English version and Chinese version) to improve my English, both are ...
190 views

### Picking certain pairs according to a condition [duplicate]

I'm a Mathematica beginner and can't find out a solution to my problem. I have a list of pairs of numbers, for example something like this, but much longer: list={{2., 3.}, {3., 2.}, {5., 4.}, {4., ...
817 views

### How can I consistently get a good logistic regression fit?

I'm executing the command NonlinearModelFit[data, c/(1 + a Exp[-b x]), {a, b, c}, x] with the data being ...
1k views

### Plot FindRoot for non-trivial function

I would like to plot the results of FindRoot over certain range of inputs. I tried to do this with the code: ...
350 views

### How can you combine lines in $\LaTeX$ and lines in Mathematica?

Suppose that you want to make a report about the golden section algorithm, and you want to explain the process with text in $\LaTeX$, and in every iteration you want to show in that report the values ...
1k views

### Join a piecewise plot

I wrote some code to get a piecewise plot which is displayed correctly. Now I'd like to join the various parts of the plot, using some kind of interpolation, to get a continuous chart even though it's ...
778 views

### Save variables values and definition

I used to do a lot of programming in R and recently switched to Mathematica. One thing that bothers me is that I haven't found a way to save variables, their values and definition! Let's look at an ...
833 views

### How do I read a CSV file and remove comments from it

I have very recently started using Mathematica 9.0 Home Edition and am trying to understand it as best I can so please be tolerant ;). I have a file of data (sugar.csv) which contains blood sugar ...
519 views

### Combining and separating sums

How can I combine or separate sums in Mathematica in the way that Together or Expand work for rational expressions？ For ...
829 views

### How can I control the number format of exported data?

I'm having issues while exporting a tables of numerical values to "*.dat" data files. Here's the thing, sometimes when I export a table, I get more decimals on some random values. The problem is that ...
592 views

### How to combine some elements of a list?

In order to simplify my expression, I face a list manipulation problem. For example, given the input list ...
782 views

### Trying to plot a velocity profile in x-y plane

I have a velocity profile for two liquids on top of each other in a pressure driven channel. The profile is supposed to be parabolic. I plotted them up, but I can't manage to plot them in the x-y ...
526 views

### Deleting Print results

While playing around with $Pre and$Post I created this very annoying piece of code: ...
458 views

### Running external pdflatex command and importing the generated PDF document

There have been a couple of questions about incorporating labels and equations that were typeset in $\LaTeX$ into a Mathematica notebook. Ideally, this requires running ...
824 views

### How can I solve Tan[t] - t == F[x] for t as a function of x?

How can I solve the equation Tan[t] - t = Ax, where A is a constant for t[x]? I know that ...
279 views

### Parallel PowerMod

Is there anyway to parallelize the PowerMod function? Here is my Left-To-Right modular exponentation: ...
3k views

### Plot Even Piecewise function

Is it possible in Mathematica to plot an even piecewise function like: $f(x) = \begin{cases} 3t , 0 \le t \le \frac{\pi}{2} \\ 3t + 6 , \frac{\pi}{2} \le t \le \pi \end{cases}$ which has ...
240 views

### Customizing FrameTicks in DistributionChart

So I have been fighting with this for a while. I'm trying to get custom frame ticks on both the left and right side of a DistributionChart. It's not going very ...
3k views

### DSolve gives complex function although the solution is a real one

I have a problem with the DSolve[] command in mathematica 8. Solving the the following 4th order differential equation spits out a complex solution although it should be a real one. The equation is: ...
2k views

### How to find palindromic numbers (Project Euler #4)?

I'm trying to solve the fourth Project Euler's problem with this: ...
526 views

### How to simplify the following trigonometry expression such that the number of used characters is minimal?

How to simplify the following trigonometry expression such that the number of used characters is minimal? (13*Cos[t] - 5*Cos[2*t] - 2*Cos[3*t] - Cos[4*t])/4 The ...
168 views

### Is there a quick way to find a built-in function by name search?

Is there a quick way to search all built-in Mathematica functions by name? Say I want to find all functions whose name contains "Graph", such as GraphPlot, NeighborhoodGraph, Subgraph, and so forth. ...
662 views

### How can I assign a Fit result to a function?

I have this code ...
208 views

Code ...
602 views

### Randomly selecting elements without repetition

I assigned energy values to each element in the array as per the program of Verbeia. The program looks like this ...
225 views

### Exchange axes in ListLinePlot

I'm sorry to do this right off the bat, but I have the following set of data: ...
377 views

### Pattern test for variables during function definition

I am having a problem with pattern testing on variables during function definition ...
100 views

### Equal flow boundary conditions

I'm having the following issue that can not find a solution , by using this boundary condition v[0, t] == u[1, t] that Mathematica does not understand, someone ...
69 views

### Create region from polygons and tangential line segments

I have two circles and tangential line segments that I want to define a region: ...
90 views

### Evaluating Real and Imaginary parts in a dispersion equation via ContourPlot [closed]

I want to reproduce a dispersion curve from P. Zou's thesis found here: http://www.ipd.anl.gov/anlpubs/2001/06/39620.pdf on Pg. 31, Eq. 2.13. The problem is, the code below only gives values for the ...
79 views

### Simplifying Expressions for FindMinimum

I am currently trying to apply the FindMinimum function to find the lowest energy of an expression. My current expression as of now is relatively complicated. It is the summation of 48 similar terms, ...
103 views

### How to use Compile to generate an $n\times n$ array using $n$ vectors

Let's consider the following: ...
62 views

### Stopping NDSolver at time of error

I am using NDSolver and WhenEvent to solve a system of differential equations. I get this message: ...
160 views

### Confusion with SplineFit (Angle calculation)

This question is continuation to this other one I am creating polymers (where each monomer is of equal length) using this method: ...
81 views

### Does DynamicModule cure Problem with Manipulate?

Hopefully, this is a final cure for the Problem with Manipulate introduced on A problem with Manipulate and then continued on Continuation of a Problem with Manipulate. Michael E2 suggested on the ...
60 views

### How to NDSolve a set of equations, one of which itself contains NIntegrate of a desired function?

How to NDSolve a set of equations, one of which itself contains NIntegrate of a desired function waited to be solved by NDSolve first? For example, ...
70 views

### How to use Buttons to run alternate Manipulate functions

I wish to use Buttons to trigger alternate Manipulates. According to the documentation: "The first argument to Button is the label" ....and the "second argument is the function that will ...
204 views

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111 views

### Difficulty with Manipulate that has same variables as other code lines in a notebook

If I write this: ...
106 views

### Color points in ListPointPlot3D

I have some 3d points with coordinates and a value assigned to each point. I want to plot the points and depending on the value use a different color. I have tried to use the answer in ListPlot3D - ...
Is there a way, or if not, how could one define a function which takes an equation in any form (for example as given by FullSimplify): $$(A+X_0) x+By=3x$$ and ...