Best way to do

[pauld11718]

import CoolProp.CoolProp as CPpy
import numpy as np
import time

len = 1000
rho = np.zeros(len)
t = np.zeros(len)
eta = np.zeros(len)
x = np.zeros(len)

def PyDir(p,h,hndl):
for i in range(1, len):
rho[i] = hndl.PropsSI("D","P",p[i],"H",h[i],"Water")
t[i] = hndl.PropsSI('T','P',p[i],'H',h[i],'Water')
x[i] = hndl.PropsSI('Q','P',p[i],'H',h[i],'Water')
eta[i] = hndl.PropsSI('V','P',p[i],'H',h[i],'Water')
return rho,t,eta,x

def PyDirn(p,h,hndl):
rho = hndl.PropsSI("D","P",p,"H",h,"Water")
t = hndl.PropsSI('T','P',p,'H',h,'Water')
x = hndl.PropsSI('Q','P',p,'H',h,'Water')
eta = hndl.PropsSI('V','P',p,'H',h,'Water')
return rho,t,eta,x

def PyDirVec(p,h,hndl):
rho = hndl.PropsSI("D","P",p,"H",h,"Water")
t = hndl.PropsSI('T','P',p,'H',h,'Water')
x = hndl.PropsSI('Q','P',p,'H',h,'Water')
eta = hndl.PropsSI('V','P',p,'H',h,'Water')
return rho,t,eta,x

h = 1e3*np.linspace(700,1500,len)
p = 1e6*np.linspace(2.8,3,len)

t1 = time.time()
(rho,t,eta,x) = PyDir(p,h,CPpy)
t2 = time.time()
print('%e'%((t2 - t1)))

t1 = time.time()
for i in range(1,len):
(rho[i],t[i],eta[i],x[i]) = PyDirn(p[i],h[i],CPpy)
t2 = time.time()
print('%e'%((t2 - t1)))

t1 = time.time()
(rho,t,eta,x) = PyDirVec(p,h,CPpy)
t2 = time.time()
print('%e'%((t2 - t1)))

5.214521e+00
5.149483e+00
4.670270e+00

What is the best way to do the same for best computational speed?

[Peter Otten]

As your timings suggest the way you pass numpy arrays directly in PyDirVec()
is certainly the most idiomatic and also the fastest approach for a library
that supports numpy.

If that's not fast enough you probably need to look into the library itself
(which seems to be written in C++ according to the link
<http://www.coolprop.org/index.html> you didn't provide).

[Disclaimer: I haven't used CoolProp and know nothing about it]