from matplotlib.pyplot import *
from numpy import linspace, arange
from matplotlib.patches import Polygon
 
x1 = linspace(0,9,100)
y1 = 3100+0*x1
 
fig = figure(figsize=(5,5))
ax = fig.add_subplot(111)
ax.grid(False)
ax.plot(x1,y1)
ax.text(3,2500,r"$PV^n=\mathrm{const}$",size=20)
ax.text(3,2000,r"Isobaric: $n=0$",size=20)
 
ax.set_ylim(0,3720)
ax.set_yticks(linspace(0,3100,6))
ax.minorticks_on()
ax.set_xlabel("V")
ax.set_ylabel("P")
 
fig.savefig("polytropic_1.png",bbox_inches="tight",\
        pad_inches=.15)

from matplotlib.pyplot import *
from numpy import linspace, arange
from matplotlib.patches import Polygon
 
x1 = linspace(0,9,100)
y1 = 3100/(x1)
 
fig = figure(figsize=(5,5))
ax = fig.add_subplot(111)
ax.grid(False)
ax.plot(x1,y1)
ax.text(3,2500,r"$PV^n=\mathrm{const}$",size=20)
ax.text(3,2000,r"Isothermal: $n=1$",size=20)
 
ax.set_ylim(0,3720)
ax.set_yticks(linspace(0,3100,6))
ax.minorticks_on()
ax.set_xlabel("V")
ax.set_ylabel("P")
 
fig.savefig("polytropic_2.png",bbox_inches="tight",\
        pad_inches=.15)

from matplotlib.pyplot import *
from numpy import linspace, arange
from matplotlib.patches import Polygon
 
x1 = linspace(0,9,100)
y1 = 3100/(x1**1.4)
 
fig = figure(figsize=(5,5))
ax = fig.add_subplot(111)
ax.grid(False)
ax.plot(x1,y1)
ax.text(3,2500,r"$PV^n=\mathrm{const}$",size=20)
ax.text(3,2000,r"Adiabatic: $n=K$",size=20)
 
ax.set_ylim(0,3720)
ax.set_yticks(linspace(0,3100,6))
ax.minorticks_on()
ax.set_xlabel("V")
ax.set_ylabel("P")
 
fig.savefig("polytropic_3.png",bbox_inches="tight",\
        pad_inches=.15)

from matplotlib.pyplot import *
from numpy import linspace, arange
from matplotlib.patches import Polygon
 
x1 = linspace(0,9,100)
y1 = 3100/(x1**4)
 
fig = figure(figsize=(5,5))
ax = fig.add_subplot(111)
ax.grid(False)
ax.plot(x1,y1)
ax.text(3,2500,r"$PV^n=\mathrm{const}$",size=20)
ax.text(3,2000,r"Other: $n=4$",size=20)
 
ax.set_ylim(0,3720)
ax.set_yticks(linspace(0,3100,6))
ax.minorticks_on()
ax.set_xlabel("V")
ax.set_ylabel("P")
 
fig.savefig("polytropic_4.png",bbox_inches="tight",\
        pad_inches=.15)

from matplotlib.pyplot import *
from numpy import linspace, arange
from matplotlib.patches import Polygon
 
x1 = [1,1]
y1 = [0,3720]
 
fig = figure(figsize=(5,5))
ax = fig.add_subplot(111)
ax.grid(False)
ax.plot(x1,y1)
ax.text(3,2500,r"$PV^n=\mathrm{const}$",size=20)
ax.text(3,2000,r"Isochoric: $n \rightarrow +\infty$",size=20)

ax.set_xlim(0,9)
ax.set_ylim(0,3720)
ax.set_yticks(linspace(0,3100,6))
ax.minorticks_on()
ax.set_xlabel("V")
ax.set_ylabel("P")
 
fig.savefig("polytropic_7.png",bbox_inches="tight",\
        pad_inches=.15)