Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

Created by Aurelien Queffurust

Solve Later

The aim is to find all the zeros of a function within an interval.
Input :
fcn : an anonymous function (@sin, @cos...)
lb : lower bound
ub :upper bound
Output :
output : vector with unique values for which the input function return zeroThe values must be sorted in ascending order.
Example
output = find_zeros(@sin,0,2*pi) will return :
output = [0.0000    3.1416    6.2832]
since the sinus function between [0 2pi] is zero for [0 pi 2pi]

Solve

Solution Stats

122 Solutions
21 Solvers

Last Solution submitted on Dec 10, 2024

Last 200 Solutions

Problem Comments

5 Comments

5 Comments

Show 2 older comments

Tim on 17 Jul 2012

I think test case 2 might be incorrect.

Richard Zapor on 17 Jul 2012

I disagree slightly with the expected solution to test 2.
Test 2 cos between [0 2pi]
[-pi/2 pi/2 3*pi/2]

I do not believe that -pi/2 is in the interval [0 2*pi].

If -pi/2 is desired then the answer to sin [0 2*pi] should be [-2*pi -pi 0 pi 2*pi]

Richard Zapor on 17 Jul 2012

Correction of assert function.
One of the ")" is in the wrong place.
is:
assert(all(abs(find_zeros(@sin,0,2*pi) -[0 pi 2*pi]<1e-9)))

Should be:
assert(all(abs(find_zeros(@sin,0,2*pi) -[0 pi 2*pi])<1e-9))

Rafael S.T. Vieira on 4 Sep 2020

As mentioned by others, the 2nd test case is incorrect, -pi/2 is outside the interal [0,2*pi] for the function cosine. And if we do plot cos(x) on said interval, we notice that the cosine function crosses the x-axis only twice.

goc3 on 29 Sep 2020

The –pi/2 has been removed from that test case.

Solution Comments

Show comments

Problem Recent Solvers21

Problem Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers21

Suggested Problems

More from this Author30

Problem Tags

Community Treasure Hunt

Problem 837. Find all the zeros of sinus , cosinus and tangent in a given interval

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers21

Suggested Problems

More from this Author30

Problem Tags

Community Treasure Hunt

Players