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0
votes
1answer
69 views

Generate a list of values with equal number of each value

I want to create a list of 32 values such that from {a,b} I can generate ...
0
votes
1answer
28 views

Generate array of every $n^{th}$ integer between two bounds [closed]

I want to generate the series {1930, 1934, 1938, ..., 2014} with Mathematica. I found that I can use Sum[2014-m*4, {m, 20}] to ...
2
votes
1answer
106 views

Plot 3D boolean Array or matrix in Mathematica

I have been attempting several methods to plot a 3D diagram of a n by n boolean array in Mathematica but none of them produced satisfactory result. I want the $3D$ plot to have a cube when ...
5
votes
1answer
140 views

How to combine matrix with array without cycles?

I am new to Mathematica. And I'm sorry for my English. I have created a matrix ($6 \times 4$) and an array ($1 \times 4$). I want to get another matrix that will have the first element from the array ...
3
votes
4answers
258 views

Efficient method for Inserting arrays into arrays

This is strongly related to the following Questions: Looking for a way to insert multiple elements into multiple positions simultaneously in a list Building matrices by attaching vectors (columns) ...
3
votes
2answers
195 views

Mapping multiple functions over an array

I am looking for an elegant way to Map multiple functions over an array. My problem looks something like this: Consider a list of functions: ...
4
votes
2answers
101 views

Values (or positions) of array row elements within a specified number of positions from target value

I have the need to collect values from the rows of rectangular arrays of arbitrary precision integers, given a target element value and allowed "distance" (positions +/- within the row from found ...
0
votes
3answers
137 views

Padding of matrix

I want to do padding of matrix a = {{x,x},{x,u}}; to ...
10
votes
1answer
161 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 ...
1
vote
2answers
97 views

2D Fourier transform of a table - ArrayPlot issue

Recently, I have encountered an issue with ArrayPlot after performing a Fourier transform of a table. Picture presented above is an ArrayPlot of a 2D table. Using Fourier on this 2D table I obtain ...
0
votes
1answer
50 views

Extracting second value of each sublist [duplicate]

How can one get the second value of every array inside the outside array? I have the following data data = {{10, 20}, {30, 40}, {50, 60}}; I want to extract ...
0
votes
0answers
39 views

Generating the set of all three-dimensional binary arrays distinct under rotation and reflection?

How can I automatically generate all possible three-dimensional binary arrays of size $(x_1 \times x_2 \times x_3$) where each array is distinct from all others with respect to rotation and reflection ...
4
votes
3answers
245 views

Finding connected components in an array

I have an $w\times h$ array with non-negative integers. I wish to partition the set of coordinates $(c,r)$ with $1\leq c \leq w$ and $1\leq r \leq h$, in subsets, so that each subset corresponds to a ...
1
vote
2answers
65 views

Unknown limit of an array of area integrals

Could someone explain why Mathematica can't finish computing this limit (this is a limit of an array, when n -> Infinity (n ...
1
vote
3answers
119 views

More elegant/efficient solution to browse through an array

I have an array of lists and want to correlate every list with each other like this: ...
0
votes
2answers
71 views

Specifying an array that may have an unknown number of entries [duplicate]

Say I'm running some process of unknown duration, and during the process, I need to periodically record the state of some variable. If we knew exactly how long the process took, we could simply ...
10
votes
2answers
474 views

Finding all possible solutions to a math mind game

In the example below the letters shall be replaced by numbers. The numbers are from 1 to 9, and each letter has the same number ...
2
votes
2answers
38 views

Specifying an array with a specific number of copies of two elements

To specify an array of length L in Mathematica, where each entry is someElement, I'm accustomed to writing: ...
1
vote
3answers
85 views

Detecting the existence of an element in a subarray with specific properties

If I have an array that looks like this: ...
5
votes
0answers
215 views

How to extract structured array data from DefineDLLFunction in Mathematica

I want to use my Bluechip PCI-ADC acquisition card in Mathematica via his dynamic link library “Bcdll32.dll”; (used to access functions on my PCI data acquisition cards). My problem is the function ...
5
votes
3answers
156 views

How to make a control array of buttons or togglers?

An array of buttons From time to time I wish I had a control array of the sort native to Visual Basic. A control array of buttons would be a table of buttons in which each button "knows" its ...
0
votes
3answers
93 views

List of squareful, cubeful, etc. numbers

The following works: ...
0
votes
0answers
26 views

Convert separate digits of a number into an array [duplicate]

Is it possible to convert the digits of a number such as Pi into an array? It's supposed to be something like this: Digits = {3, 1, 4, 1, 5, 9, 2, 6, 5, 3...}
0
votes
0answers
37 views

Why might ListStreamPlot fail to cover StreamPoints?

I have a pretty sparse array of vectors (in the colloquial sense that it covers the domain sparsely; it's not a SparseArray). ...
3
votes
3answers
128 views

Lists - pairing up

I have two (fairly large) lists of equal length & would like to pair them up. eg - from: a = {{0, 1}, {0, 2}, {0, 3}}; b = {{1, 2}, {1, 3}, {1, 4}}; I would ...
6
votes
1answer
184 views

Is matrix multiplication automatically done in parallel in Mathematica 9?

In good old Mathematica versions (5.2, 6.0), matrix multiplication was automatically done in parallel. For example, on an 8-core machine, define two square real matrices: ...
1
vote
2answers
74 views

How do I assign specific data points in an array to a new array?

I am trying to learn how to script/program in mathematica and I am retyping some simple C and FORTRAN programs into Mathematica as a way to learn. I am writing a Monte Carlo code to calculate the ...
6
votes
3answers
193 views

How to Flatten Array of Arrays of the highest order in a simple way?

I have a matrix of matrices, given in the following code. I want to flatten the array... ...
3
votes
7answers
311 views

Concise way to generate multiset lists

I wrote the following to generate a multiset with the same number of items over a fixed range: ConstantArray[#, 3]& /@ Range[9] // Flatten ...
1
vote
1answer
153 views

Formatting plot of symmetric points differently to asymmetric points

From an array of numbers, I would like to determine (and then colour appropriately) which points are symmetric about a given axis (here, $x = 1/2$), and which are not. For example, form this: ...
1
vote
2answers
158 views

How to apply function f for each time value t, to each pixel from image, resulting in t images

I have a 2D array of complex values and I want to apply a function to every entry of the array, for every timepoint t in a list. I know how to apply my function to one entry for every time t in a ...
6
votes
2answers
161 views

Get information about a stack of images, without plotting it

A very long time ago I used Mathematica for a few months and found it very intuitive. Now for my work I use MatLab. I was just trying some stuff out with Mathematica again and there is something I ...
0
votes
1answer
113 views

Find if element exists in N-dimensional array

I was wondering if there was a more elegant way of finding whether an element exists in an N-dimensional array. The way I would do it is: ...
1
vote
2answers
81 views

Binning sequential sets of elements together in a list

Given a list of the form: {{1,2,3,4,5},{6,7,8,9,10},{11,12},{13,14,15,16},{17,18,19,20,21,22,23},{24},{25,26},{27},{4}} How can I bin each sequential set of N ...
6
votes
5answers
275 views

A fast way to calculate the median difference between pairs of elements

I have a list of coordinate pairs, take for example the following list of three pairs: ...
3
votes
0answers
59 views

Extending listability to coordinates [duplicate]

I noticed that one can subtract a since real number value from all elements in an array by writing something like {5, 4, 3, 2, 1} - 5 which outputs ...
0
votes
0answers
22 views

Pruning a list of points to find the largest clique of points with a minimum threshold point-to-point Euclidean distance [duplicate]

I have a array of points (which we'll just create randomly here): pointList = Table[{RandomReal[{0, 5}], RandomReal[{0, 5}]}, {i, 1, 100}]; I'd like to find the ...
0
votes
1answer
94 views

Computing a mean of median list of points

Given a array of lists with the same number of here N = 10 elements: ...
1
vote
1answer
144 views
6
votes
4answers
258 views

Inserting points along a linear interval between adjacent coordinates in an array

Say I have a list of coordinates in an array {{0, 0}, {0, 1}, {1, 1}} I'd like to create a new array where, between each pair of nearest-neighbor coordinates in ...
3
votes
1answer
146 views

How can I make ArrayPlot use one pixel per plot point? [duplicate]

If I ArrayPlot an {1200,1600} matrix, the result is a plot with ImageDimensions of ...
4
votes
1answer
116 views

DeleteCases vs. DeleteDuplicates for removing points within a critical Euclidean distance

I'm attempting to remove all points in an array which are within a Euclidean distance "ThresDist" of one-another. Using the command: ...
5
votes
2answers
255 views

Pruning elements in an array based on the existence of similar elements in adjacent arrays

Imagine I have a series of particles floating around in $\mathrm{R}^3$, where, at any given time, particles can pop into and out of existence. Here, for some number of time points, $(t_1, \dots, ...
5
votes
2answers
170 views

How can I use Pick[] to select items in one list when a value in a corresponding list is $\leq$ some value?

Imagine I have two list: List1 = {0, 1, 0.6, 0.5, 1.2, 0.4}; List2 = {"a","b","c","d","e","f"}; How can I use Pick to return a third list consisting of items in ...
0
votes
2answers
51 views

Efficiently adding a fixed real numbered value to a set of elements in an array

Imagine I'm trying to add some value $r$ to each element in a very large array $L$. Take for example: L = Table[RandomReal[{0,1}],{q,1,10^7}]; r = 0.0032; I can ...
2
votes
3answers
94 views

Reversibly merging sets of $k$ adjacent elements in an array

Say I have an array of the form: ExampleArray = {{1}, {2}, {3}, {4}, {5}, {6}, {7}, {8}, {9}, {10}, {11}, {12}}; I'd like to be able to reversibly merge sets of ...
0
votes
2answers
118 views

Taking averages at certain intervals

I am trying to take averages of a large two dimensional array at certain intervals. For example, for the first row, I want to take K averages of 500 values. Here is what I am trying ...
0
votes
2answers
63 views

Selecting a coordinate in a list with the smallest displacement from a point [closed]

Imagine I have a list like the following: list = {{-0.00620663, -0.0103077}, {-0.0065754, 0.00995827}, {-0.0105642, 0.00765869}, {-0.0121962, 0.00329474}}; Is ...
3
votes
2answers
307 views

Importing data into an array, column by column

I'm building a large matrix having different sized rows consisting of a few columns. The different columns are imported .txt files. Why can't I build the matrix column by column? For example, I ...
2
votes
1answer
236 views

Finding a fixed vector which minimizes the pairwise distance between noisy elements in two unordered arrays

Let $A$ and $B$ be two sets of $d$-dimensional coordinates of comparible (though not necessarily equal length). For example, here we can set $d = 3$ and have normalized values like: ...