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Otter-NumericCalculus/yoshi_otter/interpolation/__interpolation.py

184 lines
4.4 KiB
Python

from typing import Callable, Any
from yoshi_seals import process as sl
import numpy as np
class Interpolation:
"""
Data should be organized in a dataframe of two columns: X and Y
"""
def __init__(self, data) -> None:
self.data = data
self.polynomial = self.Polynomial(self.data)
def minimums(self) -> Callable[[Any], float]:
theta = 0
# somatorio de x
for i in range(self.data.shape[0]):
theta += self.data.X[i]
eta = 0
# somatorio de y
for i in range(self.data.shape[0]):
eta += self.data.Y[i]
sigma = 0
# somatorio de xy
for i in range(self.data.shape[0]):
sigma += self.data.X[i] * self.data.Y[i]
omega = 0
# somatorio de x^2self.dself.dself.d
for i in range(self.data.shape[0]):
omega += self.data.X[i] ** 2
a = (self.data.shape[0] * sigma - theta * eta) / (self.data.shape[0] * omega - (theta ** 2))
b = (theta * sigma - eta * omega) / ((theta ** 2) - self.data.shape[0] * omega)
ym = 0
for i in range(self.data.shape[0]):
ym += self.data.Y[i] / self.data.shape[0]
sqreq = 0
for i in range(self.data.shape[0]):
sqreq += ((a * self.data.X[i] + b) - ym) ** 2
sqtot = 0
for i in range(self.data.shape[0]):
sqtot += (self.data.Y[i] - ym) ** 2
r2 = sqreq / sqtot
return lambda x: a * x + b, r2
class Polynomial:
def __init__(self, data) -> None:
self.data = data
def vandermonde(self) -> Callable[[Any], float]:
matrix = np.zeros((self.data.shape[0], self.data.shape[0]))
for k in range(0, self.data.shape[0]):
matrix[:, k] = self.data.X[:] ** k
array = np.array(self.data.Y.tolist()).reshape(self.data.shape[0], 1)
A = sl.gauss(matrix, array)
def f(coefficient_matrix, x):
y = 0
for i in range(0, A.shape[0]):
y += coefficient_matrix[1][i] * (x ** i)
return y
return lambda x: f(A, x)
def lagrange(self, x: float) -> float:
def L(k, x):
up = 1
down = 1
for i in [x for x in range(self.data.X.shape[0]) if x != k]:
up = up * (x - self.data.X[i])
for i in [x for x in range(self.data.X.shape[0]) if x != k]:
down = down * (self.data.X[k] - self.data.X[i])
return up / down
y = 0
for i in range(self.data.X.shape[0]):
y += self.data.Y[i] * L(i, x)
return y
def newton(self, x: float) -> float:
d = np.array(np.zeros((self.data.shape[0], self.data.shape[0])))
d[0] = self.data.Y
i = j = 0
while i < self.data.shape[0]:
while j < (self.data.shape[0] - (i + 1)):
d[i + 1][j] = (d[i][j + 1] - d[i][j]) / (self.data.X[(i + 1) + j] - self.data.X[j])
j += 1
i += 1
j = 0
def f(x):
y = d[0][0]
i = 0
while (i + 1) < self.data.shape[0]:
mult = 1
k = 0
while k <= i:
mult = mult * (x - self.data.X[k])
k += 1
y += d[i + 1][0] * mult
i += 1
return y
self.f = f
return f(x)
def gregory(self, x: float) -> float:
h = self.data.X[0] - self.data.X[1]
d = np.array(np.zeros((self.data.shape[0], self.data.shape[0])))
d[0] = self.data.Y
i = j = 0
while i < self.data.shape[0]:
while j < (self.data.shape[0] - (i + 1)):
d[i + 1][j] = (d[i][j + 1] - d[i][j]) / ((i + 1) * h)
j += 1
i += 1
j = 0
y = d[0][0]
i = 0
while (i + 1) < self.data.shape[0]:
mult = 1
k = 0
while k <= i:
mult = mult * (x - self.data.X[k])
k += 1
y += d[i + 1][0] * mult
i += 1
return y