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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 From http
Step1:  Altura sobre el nivel del mar
Step2:  Altura del edificio
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Python Code:
def htop(h,units='milibar'):
    '''h in m
    returns p in Pa'''
    k=1
    if units=='Pa':
        k=1
    if units=='mmhg':
        k=7.50061683/1000. 
    if units=='milibar':
        k=1./100.
    return 101325*k* (1. - 2.25577E-5* h)**5.25588
def ptoh(p,units='milibar'):
    '''p in m
    returns height in m above the sea level'''
    return 44330.76*( 1-(100*p/101325)**(0.1902631) )
import numpy as np
import pandas as pd
ap=pd.DataFrame()
ap['p']=np.loadtxt('p.txt')
ap['h']=ptoh(ap.p)
Explanation: From http://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html
The Astro Pi measures presures in milibar
For $h$ in m
\begin{align}
 p\ \text{Pa}=&101325(1. - 2.25577\times 10^{-5} h )^{5.25588}\
\frac{1}{100} p\ \text{milibar}=&101325(1. - 2.25577\times 10^{-5} h )^{5.25588}
\end{align}
For example, if $h=10000$ m:
End of explanation
plt.plot(ap.index,ap.h,'r-',lw=2)
plt.xlabel('Tiempo transcurrido (s)',size=20)
plt.ylabel('Altura del edificio (m)',size=20)
Explanation: Altura sobre el nivel del mar
End of explanation
plt.plot(ap.index,ap.h-ap.h.min(),'r-',lw=2)
plt.title('La Altura Entrebosques del S3 al 26 es %g m' %round( (ap.h.max()-ap.h.min()),1 ))
plt.xlabel('Tiempo transcurrido (s)',size=20)
plt.ylabel('Altura del edificio (m)',size=20)
ap.p.min()
ptoh(ap.p.min())
print('floor')
raw_input()
print('head')
raw_input()
print('height')
Explanation: Altura del edificio
End of explanation
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