# All Questions

175 views

### Exporting a list as RawData or Data

My problem is quite simple yet I do not seem to figure out the solution to it. I am simply trying to export a list in Mathematica, actually a list of lists of lists etc, something like ...
104 views

To help distinguish the various dimensions, I have a model which outputs a vector in a series of time intervals, I then construct a list of these models. Next, I would like to compute the outer ...
316 views

### Drop selection of columns from a ragged array

I have an application where I need to drop some arbitrary list of columns from a ragged array (where of course the shortest array rows have at least all the specified columns). E.g., given a ragged ...
121 views

### How to define a function that operate with a base case recursively? [duplicate]

Let's start from the simplest case: say I have a function $f(x)=x$, and let's say I want to define a new function (of $x$) to be its $n$-th power $(f(x))^n$. How should I write the code? I tried: ...
44 views

### Functional derivatives in Feynman Path Integral [duplicate]

Is there any package that can simplify functional derivatives in path integrals? For instance the expression (integrate over, $x,y,z,u,v,r,s$): ...
692 views

### Differential operator squared

I defined a one-dimensional momentum operator $\hat{p}=-i\hbar\frac{\partial}{\partial{x}}$ in Mathematica p = -I * h * D[#, x]& and I want to get the ...
364 views

### Elliptic curve cryptography in Mathematica

I can find no resources for doing elliptic curve cryptography. I have used the finite field package, but I find it cumbersome and it does not seem to have any builtin methods for ECC. How can I get ...
87 views

### Square root of a value defined in a finite field?

I am trying to find the right way to compute the square root of a number defined in a finite field. For example, ...
339 views

### How to get CUDALink working on linux (Crunchbang Waldorf) with NVS 3100m

I am trying to get CUDALink working on my laptop. I am running Crunchbang "waldorf" which is based on Debian 7 "wheezy". I am a linux novice. The issue is that Mathematica can "see" the nVidia ...
100 views

### Are there some other ways to solve a second PDE except DSolve?

I have a partial differential equation as follows: $$\frac{\partial p(x,t)}{\partial t}=\text{Dp} \frac{\partial ^2p(x,t)}{\partial x^2}-\frac{p(x,t)-\text{p0}}{\tau }$$ What I try to do was to get ...
321 views

### Plotting Zeros of a Complex Variable

I'm trying to plot the zeros within a certain distance from the origin using Mathematica of a given function (in my case, partial sums of the Zeta Function). I've tried plugging in simple functions, ...
53 views

### Addition of sparse array objects [duplicate]

Bug introduced in 9.0.0 and fixed in 10.0.0 I have been having some trouble with the addition of large (but very sparse) matrices using SparseArray. Here is the simplest example to illustrate the ...
438 views

### Paste letter grades B+ , C-, A, B into notebook and not get B+C-AB

I have worked for two days to find a way through this problem. I am porting my student grade records into Mathematica from spreadsheets, or sometimes from my college web sites, or sometimes from my ...
514 views

### Insert a linebreak and character repeatedly into a very long string

Suppose I have a very long string ...
114 views

### Importing and manipulating data in HDF format

I have two matrices A1 and A2 in HDF format. I use the following code to import them. ...
192 views

### Plotting data in a weird format

I have a lot of data on the following form: data = {{param1,param2,param3,param4,{{x1,y1},{x2,y2},...,{xn,yn}}},...} The first variables in each sublist are ...
580 views

### NDSolve example - analytical vs numerical solution. How to specify initial conditions?

So, I have the following equation: y[t]^-3 == w^2 y[t]/t^2 + y''[t] where w^2 = (t0 k0)^2. Analytic solution is easy to ...
810 views

### How to draw rectangle in mathematica with arrow

I have a basic question but i cant seem to find an answer for it. How do i draw a rectangle in mathematica with either clockwise or counterclockwise arrow heads. In this picture i know two points ...
458 views

### InstallR on OS X with external R installation

How do I InstallR on OS X to use my already installed and configured R? Simply using ...
941 views

### Interpolation: Unstructured grid error

If I try to make a table SimpleTable and to interpolate a function of two variables, I encounter a problem. For example: ...
90 views

### Sorting non-numerical lists [duplicate]

The Sort function will by default sort from lowest to highest. In[1]:= Sort[{3, 1, 4}] Out[1]= {1, 3, 4} However, if the list ...
297 views

### How to 'center' a Histogram

How can a generate a histogram so the peak of the distribution is at x=0? I want to center these histograms for comparison ...
151 views

### Launching external program in background process with ParallelSubmit

I work on the implementation of an image processing pipeline in Mathematica in which I also would like to use external programs to do certain processing steps. As an example I have macros for the ...
727 views

### Finding differences between Pi with varying number of decimals

I have the following code In[32]:= N[Pi, 2] Out[32]= 3.1 In[33]:= N[Pi, 1] Out[33]= 3. In[34]:= N[Pi, 2] - N[Pi, 1] Out[34]= 0.*10^-1 Why can't Mathematica ...
487 views

### Polynomial GCD over a ring (with composite characteristic)

I'd like to implement the "Franklin-Reiter Related Message Attack" (see section 4.3 of Boneh's paper). As part of the implementation, I require to compute the GCD of two polynomials over ...
247 views

### Import a large no. of image from a folder together to Mathematica and assign a variable to each of the image [duplicate]

I am using Mathematica for the processing of images. For this I have to process a lot of images. Currently, I import one by one of the images to run the simulation. I want to import all the image ...
218 views

### intersection of two lines with a slope slider

I am trying to build an IS/LM model with sliders for a few things including the slope of the IS curve. I am stuck getting the equilibrium ticks and dashed lines to properly follow the intersection of ...
302 views

### Convergence in NIntegrate vs Integrate

I am faced with this situation that for a certain integration, $\int _0 ^\infty \frac { \tanh (\pi \sqrt{x} )} {\sqrt{x+10} } dx$ - the command Integrate returns ...
92 views

### Strange result using NIntegrate with Max and PDF

This is really trivial and I appologise in advance if I have made a stupid error somewhere. I have been chasing down some strange results when using NIntegrate with ...
71 views

### Resolve a conditional expression including exists and forall

I don't know the Resolve function exactly, especially when involved with Exists and ForAll, ...
402 views

### Visualising Special Relativity

Mathematica newbie learning by doing (or not so far, in this case). Problem: Special Relativity - consider two inertial frames $A$ & $A'$ in relative motion. At a time $t0$ as measured in $S$, ...
83 views

### Accumulate 2D points that have the same first component [duplicate]

I have a list of points: points={{3, 0}, {3, 9}, {4, 2}, {5, 5}, {6, 9}, {6, 6}, {6, 1}, {7, 7}, {8,0}, {8, 10}}; And as you can see on the plot, there are ...
765 views

### Solve non linear system of equations

I am trying to solve a system of two equations with two unknowns. In these equations I have, a part from constants: Unknown nr 1, $$D_{\perp}$$ Unknown nr 2, $$\omega_C$$ Known function of r: ...
135 views

### Numerical method for solving a polynomial equation

I am looking for a numerical solution of a equation which contains, in general, one polynomial equation with unknown variable x. I have tried Reduce, ...
263 views

### Problem with CurrentValue[“MouseOver”] when graphics are wrapped with Deploy

Bug reproduced in: V 9.0.1 - 10.3 Please take a look at following toy example: ...
152 views

### Plot rate of change in $x$ axis of list of points

I have a list of points, that may have clusters in some of the $x$ axis values, and my goal is to get a function that shows that graphically. Something like this, but the red function is "hand ...
303 views

### Spherical harmonic derivative

Consider the following substitution Derivative[2, 0][S][th, ph] /. S -> Function[{th, ph}, SphericalHarmonicY[3, 0, th, ph]] which gives correct answer. While ...
170 views

### How to get a number from Solve [duplicate]

It's often useful to get just one number from Solve. I use the following construction for acquiring one solution from the expression returned by ...
158 views

### Patterns of function-arguments in expressions

I want a function that compares an expression with a specific pattern. The expression has always the following form: ...
147 views

### Unexpected output from oddSublists [duplicate]

I have just bought Mathematica and I'm in the process of plowing through Shifrin's great book. On page 74 the function oddSublists doesn't give me the expected ...
116 views

### CurveGraphics for 3D System of DEQs

I am using the CurveGraphics6 NB to try and do some 3D related phase portraits and graphics. The following works and produces an animation. ...
238 views

### Nested Derivative

These two expressions are mathematically the same, but when substituting with the same rule, yield different results. What is happening? ...
24 views

### $H_{\infty}$ optimization of transfer function matrix [duplicate]

I have a two-dimensional $(2 \times 2)$ transfer function matrix like this: $$G(s) = \begin{pmatrix} \frac{1}{xs+1} & \frac{1}{s+0.5}\\ \frac{3}{s+3}& \frac{1}{ys+2} \end{pmatrix}$$ The ...
137 views

### Collecting terms in an expression [duplicate]

I have an expression: ...
272 views

### Cropping a Plot without rasterization

Suppose that I make a plot of $x^2$ vs. $x$: myPlot = Plot[x^2, {x, -1, 1}, Frame -> True] If I click on the plot, I see the orange handles with which I can ...
175 views

### SSH known hosts in Windows (Error code = 124)

I had to re-install Raspbian OS and now it has new SSH key. SSH clients usually let ignore this fact and save the new key, but not now. Mathematica gives no way to go if the Host Key was changed. I ...
201 views

### Sporadic bugs in multidimensional SparseArray objects

Udate This SparseArray[] bug is (apparently) fixed on version 10.0 ...
697 views

### Most influential and/or disrupting features introduced with new versions of Mathematica

This is something that has been bugging me for ages. With every upgrade, Mathematica has added new functionalities and amended some of its bugs. In the process, though, some older functionality has ...