Create a function that will output the three roots of a cubic equation specified by the 4 coefficients listed as input. The output should be sorted using the "sort" function of matlab, to be consistent. Also, the output need only be accurate to the 4th decimal place, and the input "A" will always be non-zero and real.
Example:
A*x^3+B*x^2+C*x+D=0 --> [A,B,C,D]
x^3-6x^2+11x-6=0 --> [1,-6,11,-6]
cubicFormula([1,-6,11,-6]) --> [1,2,3]
Solution Stats
Problem Comments
3 Comments
Solution Comments
Show comments
Loading...
Problem Recent Solvers22
Suggested Problems
-
5157 Solvers
-
Omit columns averages from a matrix
620 Solvers
-
470 Solvers
-
1467 Solvers
-
Find the index of nth maximum of a row vector of real numbers
83 Solvers
More from this Author1
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
the "sorted" requirement is problematic, I would suggest you drop this requirement and simply resort the output of cubicFormula after (not before) rounding to four digits (and apply the same logic to your testsuite)...
is there maybe a several problem with the sorting method you describe/need?? :-/
The problem requires abs as 'ComparisonMethod' for sorting and the non-conjugate transpose. That's a pain that I have just become aware: ' is the conjugate transpose, and .' is the non-conjugate transpose. The conjugate operator changes the signs of complex roots.