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# Da Lu

##### Last seen: 6 dagen 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/...

9 maanden 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...

9 maanden ago

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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.

9 maanden ago

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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...

9 maanden 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....

9 maanden 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,...

9 maanden ago

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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...

9 maanden ago

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

9 maanden 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.

9 maanden ago

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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...

meer dan 2 jaar 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 ...

bijna 3 jaar 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...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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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...

bijna 3 jaar 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...

bijna 3 jaar 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...

bijna 3 jaar 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...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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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...

bijna 3 jaar 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 =...

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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

bijna 3 jaar ago

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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...

bijna 3 jaar ago

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You just measured its surface area, that is the input.

bijna 3 jaar ago

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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....

bijna 3 jaar ago

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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 = ...

bijna 3 jaar ago

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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 ...

bijna 3 jaar ago