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Author: William A. Stein
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freeze;
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/****-*-magma-* EXPORT DATE: 2004-03-08 ************************************
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MODFORM: Modular Forms in MAGMA
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William A. Stein
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FILE: degeneracy_maps.m
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$Header: /home/was/magma/packages/modform/code/RCS/degeneracy_maps.m,v 1.3 2001/05/30 18:54:29 was Exp $
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$Log: degeneracy_maps.m,v $
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Revision 1.3 2001/05/30 18:54:29 was
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Created.
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Revision 1.2 2001/05/16 04:11:55 was
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*** empty log message ***
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Revision 1.1 2001/05/16 03:51:46 was
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Initial revision
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***************************************************************************/
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/*
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intrinsic DegeneracyMap(M1::ModFrm, M2::ModFrm,
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d::RngIntElt) -> Map
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{The degneracy map M_1 ---> M_2 associated to d.
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Let N_i be the level of M_i for i=1,2. Suppose that d
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is a divisor of either the numerator or denominator of
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the rational number N_1/N_2, written in reduced form.
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If N_1 divides N_2, then this intrinsic returns
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alpha_d : M_1 ---> M_2, or if N_2 divides N_1, then this
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intrinsic returns beta_d : M_1 ---> M_2. It is an error if
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neither divisibility holds.
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}
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require Weight(M1) eq Weight(M2) :
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"The weight of argument 1 must equal weight of argument 2.";
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assert false;
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error "DegeneracyMap -- Not programmed.";
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end intrinsic;
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intrinsic DegeneracyMatrix(M1::ModFrm, M2::ModFrm,
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d::RngIntElt) -> AlgMatElt
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{The matrix of DegeneracyMap(M1,M2,d) with respect to Basis(M1) and
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Basis(M2). Both IsAmbient(M1) and IsAmbient(M2) must be true.}
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assert false;
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error "DegeneracyMatrix -- Not programmed.";
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end intrinsic;
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*/
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