My Python workspace

import numpy as np

CA = np.array([120,155,125,202,180,235,240])
t = np.array([1,2,3,4,5,6,7])

import matplotlib.pyplot as plt

plt.figure(figsize=(8,5))
plt.plot(t, CA, marker='o', linestyle='-', color='b', label='CA over Time')
plt.title('CA Values Over Time')
plt.xlabel('Time (t)')
plt.ylabel('CA')
plt.grid(True, linestyle='--', alpha=0.6)
plt.legend()
plt.tight_layout()
plt.show()

import numpy as np  
n = len(t)
t1 = t[:(n+1)//2]
g1 = CA[:(n+1)//2]
t2 = t[(n+1)//2:]
g2 = CA[(n+1)//2:]

x1 = np.mean(t1)
y1 = np.mean(g1)
x2 = np.mean(t2)
y2 = np.mean(g2)
print(x1)
print(y1)
print(x2)
print(y2)

a = (y2 - y1) / (x2 - x1)
b = y1 - a * x1

print(a,",",b)

plt.plot(t, CA, 'bo-', label='CA data')

CA_line = a * t + b
plt.plot(t, CA_line)

plt.xlabel('t')
plt.ylabel('CA')
CA_pred = a * 8 + b

plt.plot(8, CA_pred, 'gs', markersize=8,marker="x")


plt.show()

x1, y1 = t[0], CA[0]
x2, y2 = t[-1], CA[-1]

a = (y2 - y1) / (x2 - x1)
b = y1 - a * x1

CA_pred = a * 8 + b

plt.plot(t, CA, 'o') 
t_line = np.array([x1, x2])
CA_line = a * t_line + b
plt.plot(t_line, CA_line, color='red')
plt.plot(8, [CA_pred], marker='x')

plt.xlabel('t')
plt.ylabel('CA')
plt.show()

x_mean = np.mean(t)
y_mean = np.mean(CA)

a = np.sum((t - x_mean) * (CA - y_mean)) / np.sum((t - x_mean)**2)
b = y_mean - a * x_mean

CA_pred = a * 8 + b

plt.scatter(t, CA)
t_line = np.linspace(np.min(t), np.max([np.max(t), 8]), 100)
CA_line = a * t_line + b
plt.plot(t_line, CA_line, color='red')
plt.scatter([8], [CA_pred], marker='x', s=100)

plt.xlabel('t')
plt.ylabel('CA')
plt.show()