134 total contributions since 2012

Professional Interests: MATLAB - statistics - modeling

Solved

5 Prime Numbers

Your function will be given lower and upper integer bounds. Your task is to return a vector containing the first five prime numb...

1 year ago

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Pernicious Anniversary Problem

Since Cody is 5 years old, it's pernicious. A <http://rosettacode.org/wiki/Pernicious_numbers Pernicious number> is an integer w...

1 year ago

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How to subtract?

*± ± ± ± ± ± ± ± ± ± ±* * Imagine you need to subtract one...

1 year ago

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Flip the main diagonal of a matrix

Given a n x n matrix, M, flip its main diagonal. Example: >> M=magic(5); >> flipDiagonal(M) 9 24 1 ...

1 year 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...

3 years 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...

3 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...

5 years ago

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Read a Soroban Abacus

*Description* The Soroban is the name of the modern Japanese abacus. Information on reading a Soroban can be found <http://we...

5 years ago

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Back to basics 21 - Matrix replicating

Covering some basic topics I haven't seen elsewhere on Cody. Given an input matrix, generate an output matrix that consists o...

5 years ago

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Compute a dot product of two vectors x and y

x and y are input vectors, d is a number and contains their dot product

5 years ago

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Create a row array using double colon operator

Create a row array from 9 to 1, using the double colon operator.

5 years ago

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Fahrenheit to Celsius using multiple statements

Given a Fahrenheit value F, convert to a Celsius value C. While the equation is C = 5/9 * (F - 32), as an exercise use two state...

5 years ago

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Circle area using pi

Given a circle's radius, compute the circle's area. Use the built-in mathematical constant pi.

5 years ago

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Simple equation: Annual salary

Given an hourly wage, compute an annual salary by multiplying the wage times 40 and times 50, because salary = wage x 40 hours/w...

5 years ago

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Find the "ordinary" or Euclidean distance between A and Z

A, B and Z define three points in the 3D _Euclidean_ space of the form: A = [x1;y1;0]; B = [x2;y2;0]; Z = [x2;y2;z]; Find th...

6 years ago

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Test for balanced parentheses

Given the input inStr, give the boolean output out indicating whether all the parentheses are balanced. Examples: * If ...

6 years ago

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Count decimal digits of a number

* Given an integer number you have to return the number of its digits. * For example 248 has 3 digits and 1589 has 4 digits ...

6 years ago

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give nth decimal place of pi

max 15th place after the decimal point is ok for now

6 years ago

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Determine Whether an array is empty

Input a matrix x, output y is TRUE if x is empty, otherwise FALSE.

6 years ago

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Convert a vector into a number

This is a sub problem related to this problem: <http://www.mathworks.com/matlabcentral/cody/problems/621-cryptomath-addition>...

6 years ago

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Given a window, how many subsets of a vector sum positive

Given a vector: [1 0 -1 3 2 -3 1] and a window of 2, A sliding window would find: 1 + 0 = 1 0 - 1 = -1 ...

6 years ago

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Duplicate each element of a vector.

for an n-dimensional vector x, the function should return another vector 2n-dimension which each element is repeated twice. Ex...

6 years ago

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Implement a ROT13 cipher

Replace each character in string s1 with the character that is shifted 13 positions from it (wrap back to the beginning if neces...

6 years ago

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Get the length of a given vector

Given a vector x, the output y should equal the length of x.

6 years ago

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Getting the indices from a vector

This is a basic MATLAB operation. It is for instructional purposes. --- You may already know how to <http://www.mathworks....

6 years 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...

6 years ago

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Check if number exists in vector

Return 1 if number _a_ exists in vector _b_ otherwise return 0. a = 3; b = [1,2,4]; Returns 0. a = 3; b = [1,...

6 years ago

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surface of a spherical planet

you just discovered its circumference, that is the input.

6 years 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 = ...

6 years 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 ...

6 years ago