# All Questions

6 views

### Why doesn't this pattern work? [on hold]

I want the in-built function Count to count the elements in a list which are greater than a value. Example: Count[{1, 1, 2, 3}, (# > 1.5) &] Why doesn't ...
20 views

### Solve with variables as single vector

Say I have a set of equations where the unknown variables are the elements of a vector $c=(c_1,c_2,\ldots)$ and want to solve it for $c$. Is there a way to do this with ...
15 views

### Compile with modification of arguments' values

Is it possible to compile while changing the value of the arguments? How do I do this? As an example: ...
13 views

### Bug(?) in version 10: Tooltip and ListPointPlot3D

The coordinates of a point in a three dimensional graph can be shown in a tooltip: ...
15 views

### How to use a C compiler without having SystemModeler

In this question the answer given implies that I must compile a certain function. When I try to compile I get the error A C compiler cannot be found on your system. Please consult the ...
18 views

### Find all roots in range

Is there any way to check for all roots in a range? Jens' findAllRoots function is pretty good, but runs at approx. 10% of roots missed when I ran a quick check on ...
62 views

### Colorize Grayscale Image

I have a grayscale image that contains two objects. The grayscale pixel values can be divided into three intervals where two of them represent objects and the third represents the background. The ...
5 views

### Unprotect fails the first time, works on second pass

I am redefining some of the standard math functions. I know this is dangerous, so I am trying to be extra careful. (For instance, in the redefinitions, I make sure to only match a custom head) The ...
16 views

### How can I use multiple Textures in Graphics3D

I am creating a Graphics3D object for a box using 6 Polygons (1 per side). I can use one single Texture on one or more sides but I can not find a way to use different Textures for different sides of ...
14 views

### Using conditionals to check if LinearSolve found a solution

Is there some way to check if LinearSolve found a solution using conditionals in Mathematica 9? I need to solve a large number of linear equations, but I am only interested in the cases where there ...
27 views

### ListContourPlot in V10

It seems that I obtain different results when using ListContourPlot under V9 and V10. Using this datafile http://www.4shared.com/file/4CWeOCO9ba/cm_online.html ...
27 views

### Nothing happens when I click the mouse clicked on my graphics

I wrote codes to record list of coordinates when mouse clicked. It is expected that the coordinates should be plotted dynamically. But actually nothing happened. Can anybody help me to find the ...
37 views

### How do I get a Do function to create a list?

I have a Do function which gives me a column of expressions. How can I get the Do function to give me these expressions in a list. i.e The do function gives me this: a b c d I would like it do give ...
47 views

### Rotate points by 60° in 2D

I wrote this code, to rotate a list of points 60° about the first point in the list in 2D, but Mathemtica says: "Recursion depth of 1024 exceeded."
33 views

### Vertex manipulation/simplification in graph?

Given a Graph such as the one produced with the following code ...
47 views

### How to define multiple functions using a for command

Let's say I want to plot 10 graphs of those following functions. Since they are recursive functions, I cant make a table with 10 different initial conditions because Mathematica stores each value ...
118 views

### How to join two strings one of which is Subscript?

If I write this one str=Subscript["x","y"]; StringQ[str] False How can I get str as string?
21 views

### Plots to check all assumptions of linear regression

I'm running a linear regression with LinearModelFit and would like to plot graphs to check the assumptions of linear regression: linearity, independence of the ...
16 views

### How does Mathematica use system environment variables?

Is there a common way in which environment variables are accessed, stored, or used by the kernel? Some standard practice used by WRI programmers? There are built-in functions for querying and setting ...
43 views

### Open a .txt file in Mathematica [on hold]

i have a .txt file written for Mathematica, but wenn I open it with Mathematica, there is just an unreadable text and no graphs and simulations like it should actually be, could you tell me how to ...
40 views

### Tooltip with ListLinePlot and interpolation

Is it possible to get the coordinates of any point on a graph using Tooltip, ListLinePlot and interpolation ? For example on this simple example ...
308 views

### Check if two lists are equal in any order

Suppose I have two lists, how can I efficiently check if the two lists are identical up to permutations of the elements? For example I would like the function to output: ...
31 views

58 views

### Is there a way to stop Export if the file size is too big?

I've got code that's exporting a file, but the file might be so big that it will take up too much space on the cluster I'm using and crash other users' processes. Is there anything like ...
46 views

### Identically styled cells from ToBoxes and Cell do not align

I'm trying to generate some worksheets using NotebookWrite so that I can control the page breaks, but have got stuck on the alignment as there appears to be a ...
210 views

### How do I generate cross sections of a 3D graphic?

I would like to approximate the volume of a bottle by summing up the volume of the individual disks. I have obtained code references from a demonstration. But how do I generate the cross sections? The ...
76 views

### Mean curvature of Sphere

I am trying to calculate mean curvature of a parametric surface(like sphere), and I wrote this code based on this discussion. Here is my code: ...