apis/examples_python/alias_8py_source.html

from gams import *

import sys

import os

import subprocess

import re


def gdxdump2():

    data = '''

$onempty


Set i(*) /

'i1',

'i2',

'i3' /;


Parameter aa(i) /

'i1' 2,

'i2' 2,

'i3' 2 /;


$offempty

'''

    return re.sub( '\s', '', data)


def gdxdump1():

    data = '''

$onempty


Set i(*) /

'i1',

'i2',

'i3' /;


Set j(*) /

'j1',

'j2',

'j3' /;


Set ij(*,*) /

'i1'.'j1',

'i2'.'j2',

'i3'.'j3' /;


Alias (ii, i);


Alias (jj, j);


Alias (iijj, ij);


Parameter a(i) /

'i1' 1,

'i2' 1,

'i3' 1 /;


Parameter aa(ii) /

'i1' 2,

'i2' 2,

'i3' 2 /;


$offempty

'''

    return re.sub( '\s', '', data)


def get_data_text():

    return '''

set i   / i1*i3 /

    j   / j1*j3 /

   ij   / #i:#j /

alias (i,ii), (j,jj), (ij,iijj);

parameter

    a(i) / #i 1 /, aa(ii) / #ii 2 /;

'''


def same_gdx_dump(ws, gdxfile, expected_result):

    result = ""


    cmd = [os.path.join(ws.system_directory, "gdxdump"), os.path.join(ws.working_directory, gdxfile)]

    p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)

    result, err = p.communicate()

    result = re.sub( '\s', '', result.decode())

    return result.lower() == expected_result.lower()


def my_assert(test, msg):

    if not test:

        raise Exception(msg)


def check_alias_logic(prefix, alias_db):

    # Check number of symbols

    my_assert(len(alias_db) == 5, prefix + "alias_db should have NrSymbols=5: i,j,ij,a,aa.")


    cnt_symbols = 0

    for sym in alias_db:

        cnt_symbols += 1

    my_assert(cnt_symbols == 5, prefix + "'for sym in alias_db' should result in 5 symbols: i,j,ij,a,aa.")


    # See if we can retrieve alias sets

    my_assert(alias_db["ii"].name == "i", prefix + "We should get set i when asking for alias ii.")

    my_assert(alias_db["jj"].name == "j", prefix + "We should get set j when asking for alias jj.")

    my_assert(alias_db["iijj"].name == "ij", prefix + "We should get set ij when asking for alias iijj.")


    # Check domain logic

    my_assert(alias_db.check_domains() == True, prefix + "Check domains should be true")

    my_assert(type(alias_db["aa"].domains[0]) is GamsSet, prefix + "domain[0] of aa should be set")

    my_assert((alias_db["aa"].domains[0]).name == "i", prefix + "domain[0] of aa should point to i")


    alias_db["ii"].delete_record("i1")

    my_assert(alias_db.check_domains() == False, prefix + "Check domains should be false after removal of i1")

    alias_db["ii"].add_record("i1")

    my_assert(alias_db.check_domains() == True, prefix + "Check domains should be true after adding i1 again")


if __name__ == "__main__":

    try:

        if len(sys.argv) > 1:

            ws = GamsWorkspace(system_directory = sys.argv[1])

        else:

            ws = GamsWorkspace()


        # Create initial data containing a GAMS Alias

        # The OO API does not know about Aliases and will retrieve it as a set

        j1 = ws.add_job_from_string(get_data_text())

        j1.run()

        check_alias_logic("j1.out_db ", j1.out_db)

        j1.out_db.export("outdb.gdx")

        my_assert(same_gdx_dump(ws, "outdb.gdx", gdxdump1()), "Unexpected result of gdxdump outdb.gdx")


        # Copy constructor should preserve aliases and other

        db = ws.add_database(source_database= j1.out_db)

        check_alias_logic("db ", db)

        db.export("db.gdx")

        my_assert(same_gdx_dump(ws, "db.gdx", gdxdump1()), "Unexpected result of gdxdump db.gdx")


        db2 = ws.add_database()

        ii = db2.add_set_dc(db["ii"].name, ["*"], db["ii"].text)

        db["ii"].copy_symbol(ii)


        aa_orig = db["aa"]


        aa = db2.add_parameter_dc(db["aa"].name, [ii], db["aa"].text, )

        aa_orig.copy_symbol(aa)

        db2.export("db2.gdx")

        my_assert(same_gdx_dump(ws, "db2.gdx", gdxdump2()), "Unexpected result of gdxdump db2.gdx")


        # If the domain is an Alias, Domains should return the aliased Set,

        # but DomainsAsStrings should return the name of the Alias

        my_assert(aa_orig.domains[0].name == "i",  "The domain set should be the original set")

        my_assert(aa_orig.domains_as_strings[0] == "ii", "The domain as string should be the alias name")


    except Exception as e:

        raise Exception("\n###\n### Exception caught:" + str(e) + "\n###")