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

The aim is to find all the zeros of a function within an interval.

Input :

Output :

output : vector with unique values for which the input function return zero The 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

Last Solution submitted on Jun 02, 2020

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))

Cris Luengo on 18 Jul 2012

Yeah, the test set is wrong...

circle cos sin tan trigonometry zeros