An algorithm is a sequence of well-defined steps that defines in abstract the solution to a problem.

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How can I create a glass distortion effect in an image?

I'd like to overlay a glass jar onto an image with realistic light bending. Can anyone think of a way to automate this effect (perhaps this can be done with the raytracing package rayica)?
11
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2answers
379 views

Word Squares and Beyond

A word square is a set of words which, when placed in a grid, read the same horizontally and vertically. For example, the following is an English word square of order 5: ...
19
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3answers
734 views

Build a refined grid based on intersecting line

I honestly have no idea where to begin with this problem. In summary, I have a 2D coarse grid with an intersecting line. For an easy example, let's assume it's a 4x4 grid. I wish to pass through ...
12
votes
5answers
2k views

Finding all elements within a certain range in a sorted list

Suppose we have a sorted list of values. Let's use list = Sort@RandomReal[1, 1000000]; for this example. I need a fast function ...
3
votes
1answer
115 views

Center of quadrangular

Having 4 points A (ax, ay), B (bx, by), C (cx, cy) and D ...
11
votes
2answers
1k views

Simple algorithm to find cycles in edge list

I have the edge list of an undirected graph which consists of disjoint "cycles" only. Example: {{1, 2}, {2, 3}, {3, 4}, {4, 1}, {5, 6}, {6, 7}, {7, 5}} Each ...
4
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1answer
535 views

Computing Slater determinants

I need to compute Slater determinants. I'm wondering if I would benefit from assigning each of my functions to a variable prior to computation. I'm working with Slater determinants, but my question ...
8
votes
3answers
296 views

Faster Alternatives to DateDifference

I need a faster implementation of FractionOfYear and FractionOfMonth, which do the following: Input: A time/date specified by ...
7
votes
1answer
280 views

How can I extend BinCounts to work on Times and Dates?

I want to extend BinCounts to work on a list of times or dates, binning them by Day, Week, Hour of the Month, Day of the Year, etc... So given a list of times and a time bin spec, I need to calculate ...
29
votes
4answers
2k views

Finding a percolation path

I would like to examine percolation on a random lattice. To be exact, I wish to find the minimum length of a 'bond' needed such that the leftmost site can be connected to the rightmost site. Here is ...
22
votes
7answers
979 views

Splitting words into specific fragments

I am looking into splitting words into a succession of chemical elements symbols, where possible. For example: Titanic = Ti Ta Ni C (titanium, tantalum, nickel, carbon) A word may or may not be ...
15
votes
3answers
946 views

Effective matrix power like algorithm

First example Suppose you want to calculate the 6th power of some matrix $A$. The brute force attempt of doing this is considering $$(((AA)A)A)A)A$$ which requires a total of 5 matrix ...
35
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1answer
1k views

Adaptive sampling for slow to compute functions in 2D

EDIT: Although I have posted an answer based on my current progress, this in incomplete. Please see the "open issues" section in the answer. Most plotting functions in Mathematica adjust the ...
15
votes
5answers
428 views

Alternative ways to implement a triangular recursion

Triangular recursions are a class of algorithms that frequently turn up in computational mathematics. These recursions are expressible in the general form ...