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Lei Ru

Last seen: 4ヶ月 前 2022 年からアクティブ

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Make an awesome ramp for a tiny motorcycle stuntman
Okay, given a vector, say v=[1 3 6 9 11], turn it into a matrix 'ramp' like so: m=[1 3 6 9 11; 3 6 9 11 0; 6 9 ...

4ヶ月 前

Back to basics 23 - Triangular matrix
Covering some basic topics I haven't seen elsewhere on Cody. Given an input matrix, return a matrix with all elements above a...

4ヶ月 前

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...

4ヶ月 前

Calculate Inner Product
Given two input matrices, |x| and |y|, check if their inner dimensions match. * If they match, create an output variable |z|...

5ヶ月 前

Find the Best Hotels
Given three input variables: * |hotels| - a list of hotel names * |ratings| - their ratings in a city * |cutoff| - the rat...

5ヶ月 前

Calculate BMI
Given a matrix |hw| (height and weight) with two columns, calculate BMI using these formulas: * 1 kilogram = 2.2 pounds * 1 ...

5ヶ月 前

Plot Damped Sinusoid
Given two vectors |t| and |y|, make a plot containing a blue ( |b| ) dashed ( |--| ) line of |y| versus |t|. Mark the minimum...

5ヶ月 前

Calculate a Damped Sinusoid
The equation of a damped sinusoid can be written as |y = A.&#8519;^(-&lambda;t)*cos(2πft)| where |A|, |&lambda;|, and |f| ...

5ヶ月 前

Solve a System of Linear Equations
Example: If a system of linear equations in x₁ and x₂ is: 2x₁ + x₂ = 2 x₁ - 4 x₂ = 3 Then the coefficient matrix (A) is: 2 ...

5ヶ月 前

Verify Law of Large Numbers
If a large number of fair N-sided dice are rolled, the average of the simulated rolls is likely to be close to the mean of 1,2,....

5ヶ月 前

Find the Oldest Person in a Room
Given two input vectors: * |name| - user last names * |age| - corresponding age of the person Return the name of the ol...

5ヶ月 前

Convert from Fahrenheit to Celsius
Given an input vector |F| containing temperature values in Fahrenheit, return an output vector |C| that contains the values in C...

5ヶ月 前

Calculate Amount of Cake Frosting
Given two input variables r and h, which stand for the radius and height of a cake, calculate the surface area of the cake you n...

5ヶ月 前

Times 2 - START HERE
Try out this test problem first. Given the variable x as your input, multiply it by two and put the result in y. Examples:...

5ヶ月 前

Remove NaN ?
input -> matrix (n*m) with at least one element equal to NaN; output -> matrix(p*m), the same matrix where we deleted the enti...

5ヶ月 前

Find the sum of the elements in the "second" diagonal
Find the sum of the elements in the diagonal that starts at the top-right corner and ends at the bottom-left corner.

5ヶ月 前

Find max
Find the maximum value of a given vector or matrix.

5ヶ月 前

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....

5ヶ月 前

Finding Perfect Squares
Given a vector of numbers, return true if one of the numbers is a square of one of the numbers. Otherwise return false. Example...

5ヶ月 前

Return the first and last characters of a character array
Return the first and last character of a string, concatenated together. If there is only one character in the string, the functi...

5ヶ月 前

Number of 1s in a binary string
Find the number of 1s in the given binary string. Example. If the input string is '1100101', the output is 4. If the input stri...

5ヶ月 前

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

5ヶ月 前

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...

5ヶ月 前

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.

5ヶ月 前

Create times-tables
At one time or another, we all had to memorize boring times tables. 5 times 5 is 25. 5 times 6 is 30. 12 times 12 is way more th...

5ヶ月 前

Sum all integers from 1 to 2^n
Given the number x, y must be the summation of all integers from 1 to 2^x. For instance if x=2 then y must be 1+2+3+4=10.

5ヶ月 前

Determine whether a vector is monotonically increasing
Return true if the elements of the input vector increase monotonically (i.e. each element is larger than the previous). Return f...

5ヶ月 前

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,...

5ヶ月 前

Swap the first and last columns
Flip the outermost columns of matrix A, so that the first column becomes the last and the last column becomes the first. All oth...

5ヶ月 前

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 = ...

5ヶ月 前