112 lines
3.4 KiB
Python
112 lines
3.4 KiB
Python
import csv
|
|
import matplotlib.pyplot as plt
|
|
import numpy as np
|
|
|
|
def lerp(x, min_x, max_x):
|
|
return min_x + x * (max_x - min_x)
|
|
|
|
def remove_empty_years(emissions):
|
|
empty_emissions = []
|
|
for (year, emission) in emissions:
|
|
if emission == None:
|
|
empty_emissions.append((year, emission))
|
|
|
|
for empty_entry in empty_emissions:
|
|
emissions.remove(empty_entry)
|
|
|
|
def get_country_emissions(country: str):
|
|
emissions_path = "API_EN.ATM.GHGT.KT.CE_DS2_en_csv_v2_5995567.csv"
|
|
|
|
with open(emissions_path, "r", newline="", encoding="utf-8") as f:
|
|
# Skip first 4 lines
|
|
for _ in range(4):
|
|
f.readline()
|
|
|
|
reader = csv.reader(f, delimiter=",", quotechar='"')
|
|
header_row = next(reader)
|
|
years = list(int(header) for header in header_row[4:] if header != '')
|
|
|
|
for row in reader:
|
|
if row[0] == country:
|
|
emissions_str = row[4:4+len(years)]
|
|
emissions = list(float(emission) if emission != "" else None for emission in emissions_str)
|
|
emission_points = list(zip(years, emissions))
|
|
remove_empty_years(emission_points)
|
|
|
|
years = list(row[0] for row in emission_points)
|
|
emissions = list(row[1] for row in emission_points)
|
|
return years, emissions
|
|
|
|
def lagrange_dx_2d(
|
|
x,
|
|
x_prev, y_prev,
|
|
x_curr, y_curr,
|
|
x_next, y_next):
|
|
return (((x - x_curr) + (x - x_next)) / ((x_prev - x_curr) * (x_prev - x_next))) * y_prev + \
|
|
(((x - x_prev) + (x - x_next)) / ((x_curr - x_prev) * (x_curr - x_next))) * y_curr + \
|
|
(((x - x_prev) + (x - x_curr)) / ((x_next - x_prev) * (x_next - x_curr))) * y_next
|
|
|
|
def akima_derivatives(Xs: list[float], Ys: list[float]):
|
|
assert len(Xs) == len(Ys)
|
|
|
|
result = []
|
|
N = len(Xs)
|
|
for i in range(N):
|
|
pivot = i
|
|
if pivot == 0:
|
|
pivot += 1
|
|
elif pivot == N-1:
|
|
pivot -= 1
|
|
|
|
x = Xs[i]
|
|
|
|
x_prev = Xs[pivot-1]
|
|
y_prev = Ys[pivot-1]
|
|
x_curr = Xs[pivot ]
|
|
y_curr = Ys[pivot ]
|
|
x_next = Xs[pivot+1]
|
|
y_next = Ys[pivot+1]
|
|
|
|
result.append(lagrange_dx_2d(x, x_prev, y_prev, x_curr, y_curr, x_next, y_next))
|
|
return result
|
|
|
|
def draw_hermite_curve(X: list[float], Y: list[float], dY: list[float], scalar = 1):
|
|
assert len(X) == len(Y) == len(dY)
|
|
N = len(X)
|
|
|
|
plt.plot(X, Y, '--g', label="Originali")
|
|
plt.plot(X[0], Y[0], 'ro', label="Mazgas")
|
|
for i in range(N - 1):
|
|
plot_x = np.linspace(X[i], X[i+1], scalar)
|
|
plot_y = []
|
|
|
|
plt.plot(X[i+1], Y[i+1], 'ro')
|
|
d = X[i+1] - X[i]
|
|
for k in range(scalar):
|
|
s = plot_x[k] - X[i]
|
|
U1 = 1 - 3 * (s**2 / d**2) + 2 * (s**3 / d**3)
|
|
V1 = s - 2 * (s**2 / d) + (s**3 / d**2)
|
|
U2 = 3 * (s ** 2 / d **2) - 2 * (s**3 / d ** 3)
|
|
V2 = -1 * (s ** 2 / d) + (s ** 3 / d ** 2)
|
|
|
|
f = U1*Y[i ] + V1*dY[i ]
|
|
f += U2*Y[i+1] + V2*dY[i+1]
|
|
plot_y.append(f)
|
|
plt.plot(plot_x, plot_y, 'b', label="Interpoliuota" if i == 0 else None)
|
|
plt.draw()
|
|
plt.legend()
|
|
plt.show()
|
|
|
|
def main(country, interpolation):
|
|
years, emissions = get_country_emissions(country)
|
|
|
|
X = np.array(years)
|
|
Y = emissions
|
|
dY = akima_derivatives(years, emissions)
|
|
|
|
draw_hermite_curve(X, Y, dY, 2 + interpolation)
|
|
|
|
main(
|
|
country = "Zambia",
|
|
interpolation = 5
|
|
) |