28 lines
1.1 KiB
Python
28 lines
1.1 KiB
Python
import logging
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from sage.all import sage_eval, PolynomialRing, QQ
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class PFOperator:
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"""
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A class representing a Picard-Fuchs operator in a single variable z.
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Independent of the given order, the variables are assumed to be left of
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the derivatives.
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"""
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def _operator_from_string(self, operator_string):
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z_names = ['z%d' % i for i in range(self.no_variables)]
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theta_names = ['theta%d' % i for i in range(self.no_variables)]
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self.ring = PolynomialRing(QQ, z_names + theta_names)
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self.z_gens = self.ring.gens()[:self.no_variables]
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self.theta_gens = self.ring.gens()[self.no_variables:]
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try:
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operator = sage_eval(operator_string, locals=self.ring.gens_dict())
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except Exception as e:
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raise ValueError("Invalid operator string: %s" % e)
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return self.ring(operator)
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def __init__(self, operator_string, no_variables=1):
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self.no_variables = no_variables
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self.operator = self._operator_from_string(operator_string)
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logging.debug("Initialized PFOperator: %s", self.operator)
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