EPANETTOOLS 0.6.0.3

EPANET 2.0 calls from python

Python interface for the popular water network model EPANET 2.0 engine. EPANET2 is realeased by United States Environmental Protection Agency to public domain. This python package is copyrighted by Assela Pathirana and released under GNU General Public License version 3.

README.txt

Epanet 2.0 Python calling interface

Since version 0.4.0.1 the library is compatible with Python 3.0

What is it?

A python package enabling user to call all the epanet programmers toolkit functions within python scripts.

Installation

Windows:

Use a Python ditribution that comes with a c copiler (use WinPython or PythonXY)

pip install epanettools

POSIX (e.g. Linux, OS-X):

Download source archive (zip file), extract and run (as root)

[sudo] python setup.py install

or just type

[sudo]  pip install epanettools

Usage:

>>> import os, pprint
>>> pp=pprint.PrettyPrinter() # we'll use this later.
>>> from  epanettools.epanettools import EPANetSimulation, Node, Link, Network, Nodes, \
... Links, Patterns, Pattern, Controls, Control # import all elements needed
>>> from epanettools.examples import simple # this is just to get the path of standard examples
>>> file = os.path.join(os.path.dirname(simple.__file__),'Net3.inp') # open an example
>>> es=EPANetSimulation(file)

Node information

>>> len(es.network.nodes)
97
>>> list(es.network.nodes)[:5] # just get indexes of nodes
[1, 2, 3, 4, 5]
>>> [es.network.nodes[x].id for x in list(es.network.nodes)[:5]] # Get ids of first five nodes.
['10', '15', '20', '35', '40']
>>> n=es.network.nodes
>>> n[1].id
'10'
>>> n[94].id
'Lake'
>>> n['10'].index # get the index of the node with id '10'
1

Now links

>>> m=es.network.links
>>> len(m)
119
>>> m[1].id
'20'
>>> m[3].id
'50'
>>> m[119].id
'335'

Information about connectivity

>>> [m[1].start.id,m[1].end.id] # get the two ends of a link
['3', '20']
>>> [m[118].start.id,m[118].end.id]
['Lake', '10']
>>> sorted([i.id for i in n['169'].links]) # get the links connected to a node.
['183', '185', '187', '211']

Types of links and nodes

>>> pp.pprint(Node.node_types) # these are the type codes for nodes.
{'JUNCTION': 0, 'RESERVOIR': 1, 'TANK': 2}
>>> n[94].node_type
1
>>> n[1].node_type
0
>>> n['2'].node_type
2
>>> pp.pprint(Link.link_types) # these are the type codes for links
{'CVPIPE': 0,
 'FCV': 6,
 'GPV': 8,
 'PBV': 5,
 'PIPE': 1,
 'PRV': 3,
 'PSV': 4,
 'PUMP': 2,
 'TCV': 7}
>>> m['335'].link_type # Pump
2
>>> m['101'].link_type # PIPE
1
>>> m[1].link_type #
1
>>> [y.id for x,y in m.items() if y.link_type==Link.link_types['PUMP']] # get ids of pumps
['10', '335']
>>> [y.id for x,y in n.items() if y.node_type==Node.node_types['TANK']] # get ids of tanks
['1', '2', '3']

Network properties are available (even before we run the simulation)

>>> d=Link.value_type['EN_DIAMETER']
>>> print("%.3f" % es.network.links[1].results[d][0])
99.000

Get some results of simulation.

>>> es.run()
>>> p=Node.value_type['EN_PRESSURE']
>>> print("%.3f" % es.network.nodes['103'].results[p][5] )
59.301
>>> d=Node.value_type['EN_DEMAND']
>>> h=Node.value_type['EN_HEAD']
>>> print("%.3f" % es.network.nodes['103'].results[d][5])
101.232
>>> print("%.3f" % es.network.nodes['103'].results[h][5])
179.858
>>> d=Link.value_type['EN_DIAMETER']
>>> print("%.3f" % es.network.links[1].results[d][0])
99.000
>>> es.runq() # run water quality simulation
>>> q=Node.value_type['EN_QUALITY']
>>> print("%.3f" % es.network.nodes['117'].results[q][4])
85.317
>>> e=Link.value_type['EN_ENERGY']
>>> print("%.5f" % es.network.links['111'].results[e][23])
0.00685

Some advanced result queries

>>> print("%.3f" % min(es.network.nodes['103'].results[p])) # minimum recorded pressure of node '103'
44.169
>>> n=es.network.nodes
>>> # All nodes recording negative pressure.
>>> sorted([y.id for x,y in n.items() if min(y.results[p])<0])
['10']
>>> # Nodes that deliver a flow of more than 4500 flow units
>>> d=Node.value_type['EN_DEMAND']
>>> j=Node.node_types['JUNCTION']
>>> sorted([y.id for x,y in n.items() if ( max(y.results[d])>4500 and y.node_type==j )])
['203']

Legacy Interface

Do not use the following methods unless for compatibility!

>>> import os
>>> from epanettools import epanet2 as et
>>> from epanettools.examples import simple
>>> file = os.path.join(os.path.dirname(simple.__file__),'Net3.inp')
>>> ret=et.ENopen(file,"Net3.rpt","")

Example 1:

Retrieve simulation properties.

Basic properties of the network

>>> ret,result=et.ENgetcount(et.EN_LINKCOUNT)
>>> print(ret)
0
    >>> print(result)
    119
>>> ret,result=et.ENgetcount(et.EN_NODECOUNT)
>>> print(ret)
0
>>> print(result)
97
    >>> node='105'
    >>> ret,index=et.ENgetnodeindex(node)
    >>> print(ret)
    0
    >>> print ("Node " + node + " has index : " + str(index))
    Node 105 has index : 12

Get the list of nodes

>>> ret,nnodes=et.ENgetcount(et.EN_NODECOUNT)
>>> nodes=[]
>>> pres=[]
>>> time=[]
>>> for index in range(1,nnodes):
...     ret,t=et.ENgetnodeid(index)
...     nodes.append(t)
...     t=[]
...     pres.append(t)
>>> print (nodes)       #doctest: +ELLIPSIS
...                     #doctest: +NORMALIZE_WHITESPACE
    ['10', '15', '20', '35', '40', '50', '60', ..., '275', 'River', 'Lake', '1', '2']

Get nodes indexes on either side of a link with given index

>>> et.ENgetlinknodes(55) # note the first item in the list should be ignored.
[0, 5, 46]

>>> patId = "NewPattern";
>>> ret=et.ENaddpattern(patId)
>>> print(ret)
0
>>> import numpy as np
>>> patFactors=np.array([0.8, 1.1, 1.4, 1.1, 0.8, 0.7, 0.9, 0.0, 0.8, 0.8, 0.0, 0.0],
...                      dtype=np.float32)
>>> ret,patIndex=et.ENgetpatternindex(patId)
>>> print(patIndex)
6
>>> et.ENsetpattern(patIndex, patFactors)
0
>>> et.ENgetpatternid(6)[1]
'NewPattern'
>>> et.ENgetpatternlen(6)
[0, 12]
>>> [round(et.ENgetpatternvalue(6,i)[1],3) for i in range(1,12+1)]
[0.8, 1.1, 1.4, 1.1, 0.8, 0.7, 0.9, 0.0, 0.8, 0.8, 0.0, 0.0]
>>> et.ENsetpatternvalue(6,9,3.3)
0
>>> [round(et.ENgetpatternvalue(6,i)[1],3) for i in range(1,12+1)]
[0.8, 1.1, 1.4, 1.1, 0.8, 0.7, 0.9, 0.0, 3.3, 0.8, 0.0, 0.0]

Hydraulic Simulation

>>> et.ENopenH()
0
>>> et.ENinitH(0)
0
>>> while True :
...    ret,t=et.ENrunH()
...    time.append(t)
...    # Retrieve hydraulic results for time t
...    for  i in range(0,len(nodes)):
...        ret,p=et.ENgetnodevalue(i+1, et.EN_PRESSURE )
...        pres[i].append(p)
...    ret,tstep=et.ENnextH()
...    if (tstep<=0):
...        break
>>> ret=et.ENcloseH()
>>> print([round(x,4) for x in pres[0]])   #doctest: +ELLIPSIS
...                                         #doctest: +NORMALIZE_WHITESPACE
    [-0.6398, 40.1651, 40.891, 41.0433, ..., 0.569, -0.8864, 0.2997]

Pressure at the node ‘10’

>>> ret,ind=et.ENgetnodeindex("10")
>>> print (ind)
1
>>> print([round(x,4) for x in pres[ind+1]]) # remember epanet count starts at 1.
...                                          #doctest: +ELLIPSIS
...                                          #doctest: +NORMALIZE_WHITESPACE
    [12.5657, 12.9353, 13.4351, 14.0307, ..., 13.1174, 13.3985, 13.5478]