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Da Lu


Last seen: 2 days ago
99 total contributions since 2018

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Convert this color - RGB Vector to Hex String
Given a 3 element RGB vector corresponding to a color (given by the MATLAB color spec <http://www.mathworks.com/help/matlab/ref/...

26 days ago

Solved


Convert hex color specification to MATLAB RGB
Here's something that comes up all the time if you deal with web pages. Given a <http://www.w3schools.com/html/html_colors.as...

26 days ago

Solved


Magic is simple (for beginners)
Determine for a magic square of order n, the magic sum m. For example m=15 for a magic square of order 3.

26 days ago

Solved


Make a random, non-repeating vector.
This is a basic MATLAB operation. It is for instructional purposes. --- If you want to get a random permutation of integer...

26 days ago

Solved


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....

26 days ago

Solved


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,...

26 days ago

Solved


Generate a vector like 1,2,2,3,3,3,4,4,4,4
Generate a vector like 1,2,2,3,3,3,4,4,4,4 So if n = 3, then return [1 2 2 3 3 3] And if n = 5, then return [1 2 2...

26 days ago

Solved


Return area of square
Side of square=input=a Area=output=b

26 days ago

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Maximum value in a matrix
Find the maximum value in the given matrix. For example, if A = [1 2 3; 4 7 8; 0 9 1]; then the answer is 9.

26 days ago

Solved


Extra safe primes
Did you know that the number 5 is the first safe prime? A safe prime is a prime number that can be expressed as 2p+1, where p is...

1 year ago

Solved


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 ...

2 years ago

Solved


Reverse Run-Length Encoder
Given a "counting sequence" vector x, construct the original sequence y. A counting sequence is formed by "counting" the entrie...

2 years ago

Solved


Triangle sequence
A sequence of triangles is constructed in the following way: 1) the first triangle is Pythagoras' 3-4-5 triangle 2) the s...

2 years ago

Solved


Is this triangle right-angled?
Given any three positive numbers a, b, c, return true if the triangle with sides a, b and c is right-angled. Otherwise, return f...

2 years ago

Solved


Find a Pythagorean triple
Given four different positive numbers, a, b, c and d, provided in increasing order: a < b < c < d, find if any three of them com...

2 years ago

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Is this triangle right-angled?
Given three positive numbers a, b, c, where c is the largest number, return *true* if the triangle with sides a, b and c is righ...

2 years ago

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Area of an Isoceles Triangle
An isosceles triangle has equal sides of length x and a base of length y. Find the area, A, of the triangle. <<http://upload...

2 years ago

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Dimensions of a rectangle
The longer side of a rectangle is three times the length of the shorter side. If the length of the diagonal is x, find the width...

2 years ago

Solved


Side of a rhombus
If a rhombus has diagonals of length x and x+1, then what is the length of its side, y? <<http://upload.wikimedia.org/wikipe...

2 years ago

Solved


Side of an equilateral triangle
If an equilateral triangle has area A, then what is the length of each of its sides, x? <<http://upload.wikimedia.org/wikipe...

2 years ago

Solved


Area of an equilateral triangle
Calculate the area of an equilateral triangle of side x. <<http://upload.wikimedia.org/wikipedia/commons/e/e0/Equilateral-tr...

2 years ago

Solved


Length of a short side
Calculate the length of the short side, a, of a right-angled triangle with hypotenuse of length c, and other short side of lengt...

2 years ago

Solved


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 =...

2 years ago

Solved


No Twins?
Write a function that accepts as input a vector and returns the same vector, but retaining only the first occurrence of an eleme...

2 years ago

Solved


Roll the Dice!
*Description* Return two random integers between 1 and 6, inclusive, to simulate rolling 2 dice. *Example* [x1,x2] =...

2 years ago

Solved


Too mean-spirited
Find the mean of each consecutive pair of numbers in the input row vector. For example, x=[1 2 3] ----> y = [1.5 2.5] x=[1...

2 years ago

Solved


radius of a spherical planet
You just measured its surface area, that is the input.

2 years ago

Solved


Length of the hypotenuse
Given short sides of lengths a and b, calculate the length c of the hypotenuse of the right-angled triangle. <<http://upload....

2 years ago

Solved


Swap the input arguments
Write a two-input, two-output function that swaps its two input arguments. For example: [q,r] = swap(5,10) returns q = ...

2 years ago

Solved


Bottles of beer
Given an input number representing the number of bottles of beer on the wall, output how many are left if you take one down and ...

2 years ago

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