import numpy as np
import matplotlib.pyplot as plt
import math

def ls(x):
    if math.log10(x) < 0:
        log = -1 * math.log10(x)
    else:
        log = math.log(x)
    return log

p_finer =[0, 6.8899, 9.4189, 11.57, 20.4362, 72.6745]
logs = [0, ls(0.075), ls(0.15), ls(0.3), ls(0.6), ls(4.75)]
Dx = [0.77,0.46, 1.23]
Dy = [10, 30, 60]

plt.figure(figsize=(15, 6))
plt.title('Particle Size distribution curve plot by Anand Prabhakar', fontsize=15)
plt.scatter(logs, p_finer,c='r', s=20, cmap=plt.cm.rainbow)
plt.scatter(Dx, Dy, c = 'g', s=80)
plt.plot(logs, p_finer,c='b')
plt.legend(['observed points', 'Dx points', 'curve'], loc='lower right')
plt.annotate('D60 => 1.23', xy =(1.23, 60),xytext =(1,70),arrowprops = dict(facecolor ='r',shrink = 1))
plt.annotate('D30 => 0.46', xy =(0.46, 30),xytext =(0.6,20), arrowprops = dict(facecolor ='y'))
plt.annotate('D10 => 0.77', xy =(0.77, 10),xytext =(0.8,20), arrowprops = dict(facecolor ='r'))
plt.xlabel("log10(n); (where n = sieve size))",fontsize=12)
plt.ylabel("% finer",fontsize=12)
plt.hlines([10],  0,0.77, colors='y')
plt.hlines([30],  0,0.46, colors='y')
plt.hlines([60],  0,1.23, colors='y')
plt.vlines([0.77],  0,10, colors='r')
plt.vlines([0.46],  0,30, colors='r')
plt.vlines([1.23],  0,60, colors='r')
plt.show()