# All Questions

83 views

### Why do certain fractional values in TriangleWave not evaluate?

While answering another question I discovered that TriangleWave does not automatically evaluate when given certain fractional values, specifically fractions with a ...
218 views

### How to avoid an expensive subset of a Manipulate computation when dependent variables have not changed?

I have a Manipulate where a portion of the calculation that ends up displayed is dependent on a subset of the Manipulate control ...
87 views

### ListPlot : range from $0$

I want to plot values of a table for example: table = {0.456, 0.7899, 1.3456, 9.8908} But I want to Plot points (x,y) like: ...
56 views

### analysing data with MLF using (Oracle) Database connection

I'm testing the MLF package in Mathematica for datamining purpose. I start the databaseconnectivity with the following code: ...
20 views

### Incorporating Built-In Function Options/Parameters into Shorthand [duplicate]

Shorthand syntax provides an alternate way to apply functions and, in many cases, improves readability. A simple example would be ...
88 views

### How to distinguish expression from zero [closed]

my question is the following. I have an array, which elements are functions (say, sines of symbolic arguments). Some of the elements are zeros. I want to write code like: ...
73 views

### Limit[Sum[(2*E*n)^w/(w^(n/2+w)), {w,2,n}],n->Infinity]

I would like to show that the following (and other similar formulae) tends to zero. Limit[Sum[(2*E*n)^w/(w^(n/2+w)), {w,2,n}],n->Infinity] What's the right ...
111 views

### Adding a textfield to the function that I implemented

Adding a textfield to the function that I implemented to represent the tangent or derivative of a function, but I've added so mark errors. ...
25 views

### Threading a single abscissa through a list of ordinates [duplicate]

Suppose that I have the following list, called list. list contains elements X, ...
164 views

### Expansion with binomial coefficients

How can I get binomial coefficients in expansion of $(n x+i) (1+i x)^n+(n x-i) (1-i x)^n$, where $i=\sqrt{-1}$ and $n$ is an integer. I have no idea how to coax Mathematica to do something remotely ...
52 views

### Reap/Sow: strange behavior with tags and functions [closed]

I was trying to use strings as tags for Reap/Sow and I've found out the following strange behavior when I also add a function as the third argument of Reap[]: ...
204 views

### How to make slider in/visible in Manipulate?

I need your help with making a slider invisible and visible in a Manipulate. Here is my code: ...
39 views

### Replacing character in position

I'm trying to use Mathematica to make some work on binary data, and I'm missing something. Consider the string "111". I want to flip the last bit to become ...
23 views

### Is it possible to modify the options for a particular cell from another cell? [duplicate]

I was wondering if I can toggle the "CellOpen" state from a cell (or bunch of cells) from another cell. i.e. I am imagining having a manipulate command along the lines of: ...
125 views

### NDSolve boundary query / Extracting values from solution

I have a function $O_{2}$ with boundary conditions $O_{2}(r_{o}) = p_{o}$ and $O_{2}(g) = O_{2}'(g) = 0$. I plot it using the solver code below; ...
185 views

### How to animate 3-D figure using sequence of data [closed]

I have four points in 3-D, I want to join the points with a line. The points move with time. So I want to animate the jointed Point in three dimensions. I try to use ...
103 views

### Partial products in prime steps [duplicate]

I am trying to find out partial products going up in prime steps for Euler's product formula $$\prod_{p} \frac{1}{1-p^{-s}}$$ Trying things like ...
131 views

### Is linear interpolation applicable here

From my understanding about Linear Interpolation especially of that of Newton's Divided Difference Polynomial, we could get the value of F(x) from the given set of ...
95 views

50 views

### Extend a function defined for integers to a differentiable function of a real variable

Here is a function that calculates the probability of randomly landing on a Fibonacci number not greater than $n$: ...
235 views

### How to set magnification of image to 75%

Right click on an output image, choose magnification. There are 25%, 50%, 100% etc. But how can I set to 75%?
176 views

### Find the centre of FindGeometricTransform

I'm interested in using Solve[] to find the centre point of rotation (as an $x,y,z$ coordinate point) and axis of rotation (as a vector) from a ...
233 views

### Fitting data using a differential equation

I have data generated from two functions given below. How can I go about finding a fit of the form: y'[x] == -(a + b/(c + d y[x] + e F[x] )) where a,b,c,d,e are ...
51 views

### Mapping a function of two arguments where the 2nd arg has a fixed value

I create three random images: i1 = Image[RandomReal[1, {8, 12, 3}]]; i2 = Image[RandomReal[1, {8, 12, 3}]]; i3 = Image[RandomReal[1, {8, 12, 3}]]; I can scale a ...
145 views

### How can I define a ⊕ operator?

What is wrong with the following code? CirclePlus := SparseArray[Band[{1, 1}] -> {##}] & a_ ⊕ b_ := CirclePlus[a, b] SetDelayed::write: Tag Function in ...
71 views

### Solving polynomial equations takes infinit time

I need to solve an polynimial equation, but when i try to use Solve or NSolve in mathematica, its cant find the solution in appropriate time (i interrupted calculation after 5 hour left). The ...
145 views

### Solving algebraic equations

How may I make n and k in terms of x and y in this ...
40 views

### How to get shadow of a 3d object [duplicate]

Suppose that we have a box or a sphere or an other 3D object and a ponctual light source. How we can generate the cast shadow using mathematic? Is there any tools to render a shadow given the light ...
14 views

### Evaluating a String that is a Variable [duplicate]

I have a Variable assigned a value, say ImportantDocuments=1 How do I make N["ImportantDocuments"] evaluate to be 1 instead of ImportantDocuments I found that ...
137 views

### Passing Mathematica function via MathLink or LibraryLink to c (or c++)

I want to numerically solve the heat equation. To do so I wrote a program in C++ - It is a BVP $(\alpha T +\kappa \frac{\partial T}{\partial r}=f(t))$, where $f(t)$ is an arbitrary function, whose ...
118 views

### Why isn't Simplify completely simplifying my expression when it has all the necessary info?

I have a complex variable, and I'm trying to multiply it by its Conjugate[], which should give me a real number. So, I'm currently doing: ...
133 views

### Swap first and last names in a list

Edited to fix an inconsistency in the given example data format. I'm trying to write a simple function to load in a csv list of names which is formatted as "Lastname Firstname Initial " and ...
151 views

### PixelValue with pixel indices [duplicate]

How Can we use PixelValue with pixel indices?
365 views

### Why x = x doesn't cause an infinite loop, but f[x_] := f[x] does?

If I execute: In[1] := x = x Out[1] = x and then I evaluate the symbol x: ...
194 views

### Conditional range in a parametric plot

I have a program that needs to be done like this: ParametricPlot[ equation, If[x < 1, {x, 0, t}, {x, t, 2}]] But Mathematica didn't seem to recognize the ...
170 views

### Reduce with Integer domain, but receive a rational solution

I want to find the integer values $k$ so that D[f[x], x] has integer solutions. I tried ...
61 views

### Converting StringForm output to a string produces unexpected results

I want to compose a string that contains newlines, so I tried the following: ...
102 views

### How would I get the best quality plot into a TeX editor which includes the legends?

I have currently used "Save Selection As" after highlighting the graph and legend and then saved it as a PNG file, but the quality isn't brilliant. I am using TeXworks on Windows 7. The "Copy As ...
86 views

### Scroll bar glitch when entering full screen mode at magnifications higher than 100%

I noticed that when I enter full-screen mode in Mathematica 9 (F12 for Windows) using a magnification of 125% (or any other number higher than 100%) there is a horizontal scroll bar at the bottom of ...
87 views

### Export/Copy + Paste a plot from Mathematica Trial Version to TeX editor

I wish to get a view plots from Mathematica trial version into a TeX editor, but cannot seem to do it (unless I print the screen and crop the image which leads to bad quality). Is there a way in which ...
243 views

### Determing two Nonlinear model fits with 95% confidence bands from one data set

I have the following data which is postulated to have contributions from two different sources .....as can be seen from the confidence band, many points are out of the band. Question: How can I ...
119 views

### FindMinimum gets confused by If[…]

I'm confused by why the following doesn't work. I'm trying to numerically minimize a function that has an If statement in its definition, as follows: ...
165 views

### Forcing Mathematica to recognize a symbol without defining it

In the Mathematica front-end, symbols that have been defined are colored black and symbols with no definition associated are colored blue. This is useful to prevent spelling mistakes. Also, defined ...
251 views

### How to generate the following partitions [closed]

I have 2N items and I need to form 2N sets each with N items. The items should be evenly ...
166 views

### How can I get an approximate contour plot from a 3D plot?

I have some larger square, Hermitian matrices, M, (dimension 20, say, much more than 4) with 2 independent variables, call them x and y. I can plot the eigenvalues as functions of x and y with: ...
155 views

### Processing all files in a folder automatically

I have a lot of files in a folder that needs to be process through a function that I have written in Mathematica. I need help writing a code that would process all the files automatically. ...
106 views

### How do I save a Unicode string?

I am having a problem saving a long complicated string with Unicode characters in it. I have boiled the problem down, I think, to this minimal example: ...
140 views

### Detect a graphic primitive inside a Graphic

Please excuse me if that question is too basic but I couldn't find anything in the documentation or on here. If you consider the following Graphic I would like to ...