Alex P.

221 total contributions since 2012

Physicist, Research in Optics

Alex P.'s Badges

Solved

Filter AC, pass DC
Input x is the sampled signal vector, may have both AC and DC components. Output vector y should not contain any AC component. ...

6 years ago

Solved

Circle area using pi
Given a circle's radius, compute the circle's area. Use the built-in mathematical constant pi.

6 years ago

Solved

Given a window, how many subsets of a vector sum positive
Given a vector: [1 0 -1 3 2 -3 1] and a window of 2, A sliding window would find: 1 + 0 = 1 0 - 1 = -1 ...

6 years ago

Solved

Simple equation: Annual salary
Given an hourly wage, compute an annual salary by multiplying the wage times 40 and times 50, because salary = wage x 40 hours/w...

6 years 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,...

6 years ago

Solved

Renaming a field in a structure array
MATLAB has a <http://www.mathworks.com/help/techdoc/ref/setfield.html setfield> and a <http://www.mathworks.com/help/techdoc/ref...

6 years ago

Solved

Interpolator
You have a two vectors, a and b. They are monotonic and the same length. Given a value, va, where va is between a(1) and a(end...

6 years ago

Solved

Find state names that start with the letter N
Given a list of US states, remove all the states that start with the letter N. If s1 = 'Alabama Montana Nebraska Vermont Ne...

6 years ago

Solved

Create a square matrix of multiples
Given an input, N, output a matrix N x N with each row containing multiples of the first element of each row. This also applies...

6 years ago

Solved

MATCH THE STRINGS (2 CHAR) very easy
Match the given string based on first two characters on each string. For example A='harsa'; b='harish'; result '1' ...

7 years ago

Solved

Binary Coder
Take an input number and print the binary value of this number.

7 years ago

Problem

Travelling Salesman Problem (TSP)
Find a short way through given points. This is the travelling salesman problem. But the solution should be a fast and small fu...

7 years ago | 0

Solved

Travelling Salesman Problem (TSP)
Find a short way through given points. This is the travelling salesman problem. But the solution should be a fast and small fu...

7 years ago

Solved

Say something funny
Say something funny, or not. Your solution will be (fully automatically and objectively) scored based on how clever or funny ...

7 years ago

Problem

dir with recursive subdirectory search
Write a function that performs a recursive file search. The input and output format can be identical to the dir function. The ...

7 years ago | 0

Solved

dir with recursive subdirectory search
Write a function that performs a recursive file search. The input and output format can be identical to the dir function. The ...

7 years ago

Solved

Project Euler: Problem 9, Pythagorean numbers
A Pythagorean triplet is a set of three natural numbers, a b c, for which, a^2 + b^2 = c^2 For example, 3^2 + 4^2 =...

7 years ago

Solved

Sum the elements in either diagonal of a square matrix
Sum the elements of a square matrix that lie on either the major diagonal or anti-diagonal.

7 years ago

Solved

Find files with extension ext in the current directory
List all files with extension 'ext' in the current directory. Return a char matrix with the name of files in rows. Return 0 if...

7 years ago

Solved

Basics: 'Find the eigenvalues of given matrix
Find the eigenvalues y for a given matrix x.

7 years ago

Solved

Insert zeros into vector
Insert zeros after each elements in the vector. Number of zeros is specified as the input parameter. For example: x = [1 ...

7 years ago

Solved

Back to basics 18 - justification
Covering some basic topics I haven't seen elsewhere on Cody. Given a string with extra spaces in front and/or in back, return...

7 years ago

Solved

random picture with random colours
write a function which creates a random(x,y) matrix with random RGB colours for example create_pic(5,5) gives us a 3d matrix. ...

7 years ago

Solved

Getting the absolute index from a matrix
This is a basic MATLAB operation. It is for instructional purposes. --- You may already know how to get the <http://www.ma...

7 years ago

Solved

Back to basics 19 - character types
Covering some basic topics I haven't seen elsewhere on Cody. Return the number of punctuation characters in the input variabl...

7 years ago

Solved

Getting the row and column location from a matrix
This is a basic MATLAB operation. It is for instructional purposes. --- You may already know how to get <http://www.mathwo...

7 years ago

Solved

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

7 years ago

Solved

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...

7 years ago

Solved

Back to basics 16 - byte order
Covering some basic topics I haven't seen elsewhere on Cody. Switch the byte order of the input (i.e. if little-endian -> big...

7 years ago

Solved

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)).

7 years ago