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Matrix indexing with two vectors of indices
Given a matrix M and two index vectors a and b, return a row vector x where x(i) = M(a(i),b(i)).

14 years ago

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Function composition - harder
Write a function that accepts an arbitrary number of function handles f_1, f_2, ..., f_n and returns the composition h. That is,...

14 years ago

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System of equations
Find a solution to a system of equations represented by a |n| by |n+1| matrix. For instance, [ 2 0 4; => 2*x = 4 ...

14 years ago

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Back to basics 18 - justification
Covering some basic topics I haven't seen elsewhere on Cody. Given a string with extra spaces in front and/or in back, return...

14 years ago

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Person of interest?
given a person_of_interest, what is his_name?

14 years ago

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Infernal Recursion
Consider the recursion relation: x_n = (x_(n-1)*x_(n-2))^k Given x_1, x_2, and k, x_n can be found by this definition. Wr...

14 years ago

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Convert a numerical matrix into a cell array of strings
Given a numerical matrix, output a *cell array of string*. For example: if input = 1:3 output is {'1','2','3'} whic...

14 years ago

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Specific toolboxes
Given a string that is the name of a MATLAB toolbox, return true if it is available on the Cody solvers evaluation system, false...

14 years ago

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Make a simplified barcode
Given an integer to encode, make a barcode using the following encoding scheme: * The bar code is made from the binary versio...

14 years ago

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Return unique values without sorting
If the input vector A is [42 1 1], the output value B must be the unique values [42 1] The *values of B are in the s...

14 years ago

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Rosenbrock's Banana Function and its derivatives
Write a function to return the value of <http://en.wikipedia.org/wiki/Rosenbrock_function Rosenbrock's two-dimensional banana fu...

14 years ago

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peta to nano (x-ray)
for certain x-ray radiation, given frequency in petahertz, give wavelength in nanometer, must be accurate +/- 25%

14 years ago

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Poker Series 02: isQuads
The Poker Series consists of many short, well defined functions that when combined will lead to complex behavior. Our goal is to...

14 years ago

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Vectorize the digits of an Integer
Create a vector of length N for an integer of N digits. x=123045; x_vec=[1 2 3 0 4 5]; I happened upon a trick to do ...

14 years ago

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Create a square matrix of multiples
Given an input, N, output a matrix N x N with each row containing multiples of the first element of each row. This also applies...

14 years ago

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Back to basics 19 - character types
Covering some basic topics I haven't seen elsewhere on Cody. Return the number of punctuation characters in the input variabl...

14 years ago

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Trickier Timing
You solution should return control to main program only when the current time ends in either a 5 or 0 (e.g. the current seconds ...

14 years ago

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Fizz Buzz
Given an array of positive, non-zero, integers, return a cell array of strings the same size as the input, where each element in...

14 years ago

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Filter values in a vector
Cody often benefits from a functional style of programming. For example, your score is often better when you compose multiple fu...

14 years ago

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middleAsColumn: Return all but first and last element as a column vector
Given input A, return all but the first and last elements, arranged as a column vector. (I.e., all dimensions after the first s...

14 years ago

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Stuff the Board
You have a stack of tiles to put onto an array-like playing board. Each tile has a number (always an integer), and the board var...

14 years ago

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Sum of first n terms of a harmonic progression
Given inputs a, d and n, return the sum of the first n terms of the harmonic progression a, a/(1+d), a/(1+2d), a/(1+3d),....

14 years ago

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Find perfect placement of non-rotating dominoes (easier)
Given a list of ordered pairs, find the order they should be placed in a line, such that the sum of the absolute values of the d...

14 years ago

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Given two strings, find the maximum overlap
Given two strings s1 and s2, create a new string s3 which is as short as possible and contains both strings. If s1 = [1 2...

14 years ago

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Vector Linear sum: (p1-m1)V1+(p2-m2)V2+...(pK-mk)Vk
Calculate the sum of a Vector times coefficients expressed as two strings. Example: Normal representation [ a b c ], [ p1 ...

14 years ago

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Angle of triangle
For three unknown points a b c, given three sides ab bc ca, find three angles abc bca cab in radians. Your function should b...

14 years ago

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Double Deal
*Description* Given an input vector _v_, return the first element as the first output, the second element as the second outpu...

14 years ago

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Set defaults
Write a function that computes the volume of a cube. The function should be able to accept three inputs: the length, width, and...

14 years ago

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Parasitic numbers
Test whether the first input x is an n-parasitic number: <http://en.wikipedia.org/wiki/Parasitic_number>. ( _n_ is the second in...

14 years ago

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First non-zero element in each column
For a given matrix, calculate the index of the first non-zero element in each column. Assuming a column with all elements zero ...

14 years ago