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### Searching for an element of one list in another list and replacement

I have two lists as follow: l = {"XY", "XT", "AB", "GT"}; ll = {{"x", "g", "f"}, {"x", "y", "l", "t"}, {"x", "c", "a", "b", "z"}, {"g", "t"}}; for each ...
248 views

### How to limit the argument to binary type in mathematica function

How do I write a function that only takes binary input?
219 views

### Manipulating several values from the same interval

Some of my calculations depend on the choice of several values from the interval [-2, 2] (it is more or less interpolation of a fixed function using the points as parameters). I want to create a ...
1k views

### Solve[Tan[theta] == (b*Sin[t])/(a*Cos[t]), theta] breaks when “Reals” is added?

Mathematica solves this equation fine: Solve[ Tan[theta] == (b*Sin[t])/(a*Cos[t]), theta] // InputForm ...
285 views

### Does mathematica 9 on mac depend on these dynamic libraries?

The Mac package installing program "brew" suggests I remove some of these dynamic libraries, but I am worried that mathematica 9 might depend on them. As far as mathematica 9 is concerned, is it OK to ...
149 views

### What am I missing!? Simple symbolic sum not simplifying

I'm VERY confused: in what universe is the following not zero? FullSimplify[2*Sum[Subscript[f, i], {i, 1, q}] - Sum[2*Subscript[f, i], {i, 1, q}]] Mathematica ...
336 views

### Adding Dynamic functionality to a Graph

I would like to make the edges and vertices of a Graph interactive, a simple demonstration is to change their colors: ...
122 views

### Finding the tangents of the function in each mesh

I have a 2D graphic which contains a table of curves within a circular region. ...
157 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 ...
377 views

### Unresolved differential equation [closed]

Why can't Mathematica solve this equation as stated? ...
238 views

### Any solution to system of equations?

I need ANY combination of 8 variables which satisfy: a+b+c+d+e+f+g+h=0 a^2+b^2+c^2+d^2+e^2+f^2+g^2+h^2=1 a*b+b*c+c*d+d*e+e*f+f*g+g*h+a*h>2/3 Ideally these ...
339 views

Is there any way to get an exact solution a system of non-linear equations? The system I would like to solve is: $\quad \quad \begin{eqnarray} h_{1}x_{1}=c_{1}\\ h_{2}x_{2}=c_{2}\\ h_{3}(1-x_{1}-x_{... 3answers 707 views ### plotting two Error List Plots in one I made two ErrorListPlots ... 3answers 280 views ### Visualizing Base-10 Digits (0-9) As Corresponding Colors Is there a way I can visualize my output (which happens to be in base-10 by default) with a specific color text corresponding to the digit (0 through 9)? Here is the key for the coloring scheme: 0: ... 3answers 284 views ### How can I use NestWhileList instead of While in this case? OK, the problem occurred when I challenged with Project Euler No. 10 The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. My code is: ... 2answers 82 views ### Extra constant in solution of ODE using DSolve [closed] A paper that I have states that the solution of the ODE $$-\frac{\left(\frac{\pi k}{a}\right)^2 Y(y)}{G_y}+\frac{Y''(y)}{G_x}+\frac{8 \theta }{\pi k}=0$$ is$$Y=A\sinh\left(\frac{k\pi\mu}{a}y\right)+... 2answers 116 views ### Insert at specific resulting positions in multidimensional list? I have an initial "multidimensional" list (that is, a list that is not a vector): list0 = {{1},{2,3,4},{3,4},{5}}; and I want to insert elements ... 0answers 224 views ### Conceal GUI source code I'm working with a simple software application written in Mathematica, composing of several .nb and .m files. The application is centered around a simple mathematica GUI, which includes several ... 3answers 165 views ### BarChart without axes neglects the last zero of a list Creating a BarChart with {1, 2, 3, 0} as BarChart[{1, 2, 3, 0}, Axes -> False, Frame -> True] gives me only the first three bars, a chart identical to just ... 2answers 2k views ### Formatting results of a polynomial long division I am teaching polynomial long division to my high school students. Not a pleasant topic to have to cover. I went to use Wolfram|Alpha and obviously, internally, they have a really elegant way to ... 2answers 269 views ### How to calculate the analytical result of this singular integral? [duplicate] I'm trying to solve this integral:$I(a,b)=\displaystyle{\int_1^{\infty }\dfrac{e^{-ax}}{\sqrt{x^2-1} (1+x\sqrt{1-b^2}) (x-1/\sqrt{1-b^2})} \, dx} \,\, \,\,(a \;\textrm{real>0} \, , 0<b<1)$... 1answer 153 views ### Integrate and ConditionalExpression Output I am integrating some difficult functions and using the conditional output to place bounds on parameters to ensure integrability, but it seems that not all of the conditions are being returned. The ... 1answer 289 views ### Step Monitor option in DifferentialEvolution Using the "Step Monitor" option what exactly do I read? Does it show me the "best solution" for each population? Or does it show me each search point in the population? Also is there an integrated "... 3answers 993 views ### Function to Expand exponentials Is there a function similar to PowerExpand which expand exponentials? This would, for example, take Exp[5(a + b)] and ... 1answer 556 views ### ParametricNDSolve with variable initial conditions [duplicate] I have a large set of coupled non-linear first order ODEs describing the time evolution of multiple variables a[t]....z[t]. For most of these, I have fixed initial ... 1answer 1k views ### How to tell Mathematica not to simplify an expression While there is this question with a very similar title, it does not answer my question, which is: I have part of an input, in my case Re[Exp[I*x]] which ... 3answers 225 views ### How to transform a 3D list to a 2D list? I want to apply the command Histogram3D to an image.The image data is {{r1,g1,b1},{r2,g2,b2}...} And the input of ... 1answer 184 views ### Different outputs for Simplify In at least one instance, the same Simplify command (without using options) produces very different results on two of my computers, one Windows 7 and the other ... 2answers 140 views ### Importing Data and Devoting Their Names to Them There are some files in a directory. I have used of SetDiroctory to access all of them. SetDirectory["C:\\Users\\SE7EN\\Desktop\\mathematica\\test"]; I can visit ... 4answers 109 views ### Insert at specific resulting positions? (Another option) [duplicate] I found the answer in this post very interesting to do what I need, but I would like something where I could provide a list to be modified, a ... 2answers 175 views ### Finding Minimium Periapse Distance Between Spacecraft and Planet I have the following simple model that simulates a spacecraft orbiting Mars. What I'm hoping to do is be able to find the periapse radius of the spacecraft as I did below, except instead of using ... 0answers 104 views ### FourierCoefficient performance I encountered weird performance issue while using FourierCoefficient[]. I narrowed it down to calculating$n$-th coefficient for$\cos(nx)$. ... 2answers 380 views ### How to solve analytically a 2D Sturm-Liouville Problem? Maybe it is a syntax problem, since I haven't been using Mathematica for much time, but I haven't been able to find a similar example in internet. I am just trying to solve analitically the Sturm-... 2answers 285 views ### To change the pattern of sphere surface in Graphic3D I used of this command to draw a sphere ... 1answer 414 views ### Problem with Label in a Do loop, “nolabel” Can someone tell me why this code doesn't work and how to fix it ? Thanks. ... 1answer 107 views ### Compute the potential of confusion between two matrices I have a problem. Any help will be appreciated. In order to calculate the accuracy, sensitivity, sensibility and F1 score between diseases and their symptoms, I have two matrices with a different ... 3answers 253 views ### binning list of lists in unequal bin lengths I'm lookin for binning of ... 1answer 102 views ### Efficient Round edition with different rounding direction As pointed out in this post, Mathematica has a special version of Round that Round rounds numbers of the form x.5 toward the nearest even integer. A comment by ... 1answer 488 views ### Plot data with different confidence intervals [closed] I want to plot something like the graph in the figure. I have some points (data) and each of them is associated to two different confidence intervals, at 90% (red) and 95% (blue). These intervals can ... 1answer 173 views ### Will the solution NDSolveValue finds outside of the region I give it give me bogus results? I'm using NDSolveValue to solve Laplace's equation for a relatively simple system. I have two rectangles, separated by a small gap, which I define using RegionDifference: ... 1answer 134 views ### Palette to set Cell Options such as Background Editable and Initialization property? Hello I have found examples of codes that generate palettes to format the text of a cell (or a portion of it). I have also found codes for palettes that change the style of a cell. The latter is ... 1answer 245 views ### How to import and array of data? I'm trying to import many files which have the same name "x.data", but they end with a extension "x_code1.data". I was trying to import all files with the routine: ... 3answers 598 views ### Export NDSolve results I can see the correct result of my NDSolve when I plot them with large PlotPoints. ... 1answer 126 views ### Output of intermediate results from very long NDSolve computation into sequenced CSV files There is a problem that I was not able to solve for months, if not years, and I can't postpone it any longer. It is this: I know how to output the result of a computation from NDSolve into a file ... 1answer 173 views ### Two dimensional high oscillated numerical integral I have some problem with two dimensional integral. I want to calculate such integral. ... 1answer 964 views ### Why won't Mathematica obtain eigenvectors for this symmetric matrix? The matrix is a real symmetric 4x4: ... 1answer 356 views ### Piecewise function extraction I have a piecewise function and I'm trying to extract the different functions for different values of the parameter. I use: ... 1answer 687 views ### List Deconvolution I have some experimental data to analyse. The function$f(t)$that describes it is however convolved with a gaussian, due to finite resolution of our experiment.$f(t)$is too complicated to be ... 3answers 519 views ### Is there a way to do conditional matrix loop using 'continue' I have the following: ... 1answer 2k views ### Use Euler method to solve differential equation Use Euler's Method or the Modified Euler's to solve the differential equation${dy/dt=y^2+t^2-1, y(-2)=-2}$on$[- 2, 2]\$. Take h = 0.2 (...

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