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Read a column of numbers and interpolate missing data

Given an input cell array of strings s, pick out the second column and turn it into a row vector of data. Missing data will be i...

4 months ago

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Kaprekar Steps

6174 is the <http://en.wikipedia.org/wiki/6174_%28number%29 Kaprekar constant>. All natural numbers less than 10,000 (except som...

4 months ago

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Find the peak 3n+1 sequence value

A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...

4 months ago

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Scrabble Scores

Given a word, determine its score in <http://en.wikipedia.org/wiki/Scrabble Scrabble>. The input string will always be provi...

4 months ago

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Subset Sum

Given a vector v of integers and an integer n, return the the indices of v (as a row vector in ascending order) that sum to n. I...

4 months ago

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Find common elements in matrix rows

Given a matrix, find all elements that exist in every row. For example, given A = 1 2 3 5 9 2 5 9 3 2 5 9 ...

4 months ago

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Alphabetize by last name

Given a list of names in a cell array, sort the list by the last name. So if list = {'Barney Google','Snuffy Smith','Dagwood ...

4 months ago

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Maximum running product for a string of numbers

Given a string s representing a list of numbers, find the five consecutive numbers that multiply to form the largest number. Spe...

4 months ago

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Duplicates

Write a function that accepts a cell array of strings and returns another cell array of strings *with only the duplicates* retai...

4 months ago

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Function Iterator

Given a handle fh to a function which takes a scalar input and returns a scalar output and an integer n >= 1, return a handle f...

4 months ago

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The Goldbach Conjecture, Part 2

The <http://en.wikipedia.org/wiki/Goldbach's_conjecture Goldbach conjecture> asserts that every even integer greater than 2 can ...

4 months ago

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QWERTY coordinates

Given a lowercase letter or a digit as input, return the row where that letter appears on a standard U.S. QWERTY keyboard and it...

4 months ago

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Extract leading non-zero digit

<http://en.wikipedia.org/wiki/Benford%27s_law Benford's Law> states that the distribution of leading digits is not random. This...

4 months ago

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Sums with Excluded Digits

Add all the integers from 1 to n in which the digit m does not appear. m will always be a single digit integer from 0 to 9. no...

4 months ago

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Remove all the words that end with "ain"

Given the string s1, return the string s2 with the target characters removed. For example, given s1 = 'the main event' your ...

4 months ago

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Indexed Probability Table

This question was inspired by a Stack Overflow question forwarded to me by Matt Simoneau. Given a vector x, make an indexed pro...

4 months ago

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Summing Digits within Text

Given a string with text and digits, add all the numbers together. Examples: Input str = '4 and 20 blackbirds baked in a...

4 months ago

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Pattern matching

Given a matrix, m-by-n, find all the rows that have the same "increase, decrease, or stay same" pattern going across the columns...

4 months ago

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Trimming Spaces

Given a string, remove all leading and trailing spaces (where space is defined as ASCII 32). Input a = ' singular value deco...

4 months ago

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Find the two most distant points

Given a collection of points, return the indices of the rows that contain the two points most distant from one another. The inpu...

4 months ago

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Interpolator

You have a two vectors, a and b. They are monotonic and the same length. Given a value, va, where va is between a(1) and a(end...

4 months ago

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Return a list sorted by number of occurrences

Given a vector x, return a vector y of the unique values in x sorted by the number of occurrences in x. Ties are resolved by a ...

4 months ago

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Make a Palindrome Number

Some numbers like 323 are palindromes. Other numbers like 124 are not. But look what happens when we add that number to a revers...

4 months ago

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Reverse Run-Length Encoder

Given a "counting sequence" vector x, construct the original sequence y. A counting sequence is formed by "counting" the entrie...

4 months ago

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Elapsed Time

Given two date strings d1 and d2 of the form yyyy/mm/dd HH:MM:SS (assume hours HH is in 24 hour mode), determine how much time, ...

4 months ago

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De-dupe

Remove all the redundant elements in a vector, but keep the first occurrence of each value in its original location. So if a =...

4 months ago

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Quote Doubler

Given a string s1, find all occurrences of the single quote character and replace them with two occurrences of the single quote ...

4 months ago

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Balanced number

Given a positive integer find whether it is a balanced number. For a balanced number the sum of first half of digits is equal to...

4 months ago

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Making change

Given an amount of currency, return a vector of this form: [100 50 20 10 5 2 1 0.5 0.25 0.1 0.05 0.01] Example: Input a = ...

4 months ago

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Replace NaNs with the number that appears to its left in the row.

Replace NaNs with the number that appears to its left in the row. If there are more than one consecutive NaNs, they should all ...

4 months ago