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# Kuifeng

### Nanyang Technological University

124 2012 年以降の合計貢献数

#### Kuifeng's バッジ

How can I draw a contour line in contourf around "threshold" value
Try: contourf(X, Y, Data, [0.9999 0.9999] ) Quote "To display a single contour line at a particular value, define v as a...

7年以上 前 | 0

Omit columns averages from a matrix
Omit columns averages from a matrix. For example: A = 16 2 3 13 5 11 10 8 9 7 ...

9年弱 前

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>...

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...

Wind outward from the center ...
Create an n-by-n matrix with elements ranging from 1 to n^2 in a rectangular spiral pattern. Example if n = 5 : 21 ...

surrounded matrix
With a given matrix A (size m x n) create a matrix B (size m+2 x n+2) so that the matrix A is surrounded by ones: A = [1 2 ...

Whether the input is vector?
Given the input x, return 1 if x is vector or else 0.

Is A the inverse of B?
Given a matrix A and a matrix B, is A the inverse of B? >>A=[2,4;3,5]; >>B=[-2.5,2;1.5,-1]; >>isInverse...

Multiply a column by a row
* Given a column vector C and and a row vector R. * Output a matrix M. * Every column of M equals to C multiplied by correspon...

Rotate a Matrix
Input a Matrix x, Output y is the matrix rotating x 90 degrees clockwise

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

Determine Whether an array is empty
Input a matrix x, output y is TRUE if x is empty, otherwise FALSE.

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

Cannon Ball
Given g (acceleration due to gravity) and desired altitude x, find the minimum ground velocity of a cannon ball to reach x.

Replace May with April
For instance, if the input is input_str = 'The flowers may bloom in April'; then the output is output_str = 'The flo...

Back to basics 6 - Column Vector
Covering some basic topics I haven't seen elsewhere on Cody. Given an input vector, output true or false whether it is a colu...

Program an exclusive OR operation with logical operators
Program an exclusive or operation *without* using the MATLAB function xor. Use logical operators like |, &, ~, ... instead. ...

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

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 = ...

Counting Money
Add the numbers given in the cell array of strings. The strings represent amounts of money using this notation: \$99,999.99. E...

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

The Hitchhiker's Guide to MATLAB
Output logical "true" if the input is the answer to life, the universe and everything. Otherwise, output logical "false".

First N Perfect Squares
*Description* Return the first N perfect squares *Example* input = 4; output = [ 1 4 9 16 ];

Bullseye Matrix
Given n (always odd), return output a that has concentric rings of the numbers 1 through (n+1)/2 around the center point. Exampl...

2 b | ~ 2 b
Given a string input, output true if there are 2 b's in it, false if otherwise Examples: 'Macbeth' -> false 'Publius Cor...

Back to basics 7 - Equal NaNs
Covering some basic topics I haven't seen elsewhere on Cody. Given 2 input variables, output true if they are equal, false ot...

Back to basics 12 - Input Arguments
Covering some basic topics I haven't seen elsewhere on Cody. Return a value equal to the number of input arguments to the fun...

Sum of diagonal of a square matrix
If x = [1 2 4; 3 4 5; 5 6 7] then y should be the sum of the diagonals of the matrix y = 1 + 4 + 7 = 12

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...

Nearest
*Description* Find the value and index of the element in vector _x_ that is nearest to value _y_. _y_ should be able to be a ...