Solve the problems in hw01.pdf:
Forbidden methods/classes: numpy.roots, numpy.polynomial, numpy.poly1d
Create a general function roots(coeffs) which takes the coefficients of a univariate polynomial and returns its (complex) roots.
Input/Output specifications for roots(coeffs: numpy.ndarray) → numpy.ndarray:
coeffs : 1-dimensional numpy.ndarray that defines the polynomial coefficients starting from the highest degree term.
numpy.ndarray containing the roots of the given polynomial.
Implement the solution in a single file hw01.py. The file must contain the roots function, such that it can be imported (by the automatic evaluation) as
import hw01 import numpy as np coeffs = np.array([1, 2, 3]) res = hw01.roots(coeffs)
Upload a zip archive hw01.zip (via the course ware) containing:
hw01.json - json file containing the answers to tasks 1, 2, 3.b and 4 (see below for the description of how to create it)
hw01.py - python script containing the implemented function roots
hw01.pdf - pdf file containing the solution to tasks 1, 2, 3.a together with the companion matrices for tasks 3.b and 4 (LaTex, photos, scans, …).
hw01.zip.
Creating hw01.json:
Create an empty dictionary in Python:
solution = {}
The keys for this dictionary are “task1”, “task2”, “task3” (for task 3.b) and “task4”.
The value for the key “task1” is a list of coefficients of the product polynomial starting from the term of the highest degree, i.e. for the product polynomial 2*x^4 + 5*x^3 + 3*x^2 + 1 do
solution["task1"] = [2, 5, 3, 0, 1]
The value for the key “task2” is a list of lists of coefficients of the quotient polynomial and the remainder, respectively, starting from the term of the highest degree, i.e. for the quotient polynomial 2*x^3 + 1 and the remainder x + 2 do
solution["task2"] = [[2, 0, 0, 1], [1, 2]]
The value for the key “task3” is a list of roots to the polynomial from task 3.b (including multiplicities), i.e. for the sequence of integer roots 1, 1, 2, 3 do
solution["task3"] = [1, 1, 2, 3]
The value for the key “task4” is created in the same way as for the key “task3”.
Finally, save solution to hw01.json:
import json
with open("hw01.json", "w") as outfile:
json.dump(solution, outfile)