Perimeter of a semicircle
Given the diameter d, find the perimeter of a semicircle

Given input in radians, output to degrees

Volume Pillar
Calculate the volume of a pillar with radius l and heigth ar.

Determine the number of odd integers in a vector
Determine the number of unique odd integers in a vector. Examples: Input x = [2 5 8 3 7 1]; Output y = 4; Inp...

Finding peaks
Find the peak values in the signal. The peak value is defined as the local maxima. For example, x= [1 12 3 2 7 0 3 1 19 7]; ...

Create an n-by-n null matrix and fill with ones certain positions
The positions will be indicated by a z-by-2 matrix. Each row in this z-by-2 matrix will have the row and column in which a 1 has...

Max index of 3D array
Given a three dimensional array M(m,n,p) write a code that finds the three coordinates x,y,z of the Maximum value. Example ...

Find last zero for each column
Given a numeric array of arbitrary size, return the row index of the last zero for each column. If a column contains all nonzero...

Calculate the Number of Sign Changes in a Row Vector (No Element Is Zero)
For a row vector: V=[7 1 2 -3] there is one sign change (from 2 to -3). So, the function you write must return N=1. F...

Change the sign of even index entries of the reversed vector
change the signs of the even index entries of the reversed vector example 1 vec = [4 -1 -2 9] ans = [9 2 -1 -4] example2...

Create a vector whose elements depend on the previous element
The idea is to create a vector A whose elements depend on the previous element : *A(i+1) = 2*A(i)+1* *2 Inputs*: - A : The...

Create an index-powered vector
Given a input vector x, return y as index-powered vector as shown below. Example x = [2 3 6 9] then y should be [...

Symmetry of vector
Determine whether the vector is symmetric or not (vector could be even or odd in length). For example: x = [1 2 3 3 2 1] is s...

Reindex a vector
You are given two vectors of equal length. Vector N has numeric values (no Inf or NaN) while vector IDX has integers. Place th...

We love vectorized solutions. Problem 1 : remove the row average.
Given a 2-d matrix, remove the row average from each row. Your solution MUST be vectorized. The solution will be tested for ac...

"Low : High - Low : High - Turn around " -- Create a subindices vector
Let two vectors *lo* and *hi* be given. The job is to create a index vector like so idx = [lo(1):hi(1) lo(2):hi(2) ...]...

Remove the two elements next to NaN value
The aim is to *remove the two elements next to NaN values* inside a vector. For example: x = [6 10 5 8 9 NaN 23 9 7 3 21 ...

Matrix indexing with two vectors of indices
Given a matrix M and two index vectors a and b, return a row vector x where x(i) = M(a(i),b(i)).

middleAsColumn: Return all but first and last element as a column vector
Given input A, return all but the first and last elements, arranged as a column vector. (I.e., all dimensions after the first s...

Getting logical indexes
This is a basic MATLAB operation. It is for instructional purposes. --- Logical indexing works like this. thresh = 4...

Specific Element Count
Given a vector _v_ and a element _e_, return the number of occurrences of _e_ in _v_. Note: NaNs are equal and there may be n...

Find the largest value in the 3D matrix
Given a 3D matrix A, find the largest value. Example >> A = 1:9; >> A = reshape(A,[3 1 3]); >> islargest(A) a...

Calculate the area of a triangle between three points
Calculate the area of a triangle between three points: P1(X1,Y1) P2(X2,Y2) P3(X3,Y3) these three points are the vert...

Pizza!
Given a circular pizza with radius _z_ and thickness _a_, return the pizza's volume. [ _z_ is first input argument.] Non-scor...

Check that number is whole number
Check that number is whole number Say x=15, then answer is 1. x=15.2 , then answer is 0. http://en.wikipedia.org/wiki/Whole_numb...

MATLAB Basic: rounding
Do rounding near to zero Example: -8.8, answer -8 +8.1 answer 8

Make roundn function
Make roundn function using round. x=0.55555 y=function(x,1) y=1 y=function(x,2) y=0.6 y=function(x,3) ...

MATLAB Basic: rounding IV

MATLAB Basic: rounding III