import pyalps
import numpy as np
import math

parms=[]
parms.append({ 
                'LATTICE_LIBRARY'           :"lattices.xml",
                'MODEL_LIBRARY'             :"model_extended_basis.xml",
                'LATTICE'                   :"open chain lattice",
                'MODEL'                     :"double spin constraint", 
                'CONSERVED_QUANTUMNUMBERS'  : 'Sz',
                'Sz_total'                  : 0,
                'Jxy'                       : 1,
                'Jz'                        : 0,
	        'tcor'                      : 0,
                'h'                         : 0,
                'L'                         : 5,
                'MAXSTATES'                  :1024,
                'NUMBER_EIGENVALUES'        : 1,
                'MEASURE_LOCAL[site_exchange]'    : 'exchange_site',
                'MEASURE_AVERAGE[exchange]'    : 'exchange_site',
            } )



input_file = pyalps.writeInputFiles('my_model2_dmrg',parms)
res = pyalps.runApplication('dmrg',input_file,writexml=True)