
    <<LSFit.mesa>>
        <<Copyright © 1985 by Xerox Corporation.  All rights reserved.>>
        <<Michael Plass 10-Mar-82 15:18:23>>
        <<Doug Wyatt, September 5, 1985 1:08:55 pm PDT>>

    DIRECTORY
        Complex USING [VEC],
        Seq USING [ComplexSequence, ComplexSequenceRec, NatSequence, NatSequenceRec, RealSequence, RealSequenceRec];

    LSFit: CEDAR DEFINITIONS =
    BEGIN

    ComplexSequence: TYPE = Seq.ComplexSequence;
    ComplexSequenceRec: TYPE = Seq.ComplexSequenceRec;
    RealSequence: TYPE = Seq.RealSequence;
    RealSequenceRec: TYPE = Seq.RealSequenceRec;
    NatSequence: TYPE = Seq.NatSequence;
    NatSequenceRec: TYPE = Seq.NatSequenceRec;

    Patch: TYPE = RECORD[c0,c1,c2,c3: REAL _ 0];
    PatchSequence: TYPE = REF PatchSequenceRec;
    PatchSequenceRec: TYPE = RECORD[element: SEQUENCE length:NAT OF Patch];

    Handle: TYPE = REF StateRec;
    StateRec: TYPE = RECORD
        [n: NAT, -- number of points
            z: ComplexSequence,
            weight: RealSequence,
            t: RealSequence, -- the current best guess of parameter values
            knots: RealSequence,
            closedCurve: BOOLEAN _ FALSE,
            xPatches,yPatches: PatchSequence
            ];

    Create: PROC [sa: ComplexSequence] RETURNS [Handle];

    InitialKnots: PROC [h: Handle, nknots: NAT _ 2];

    XYat: PROC [h: Handle, t: REAL] RETURNS [Complex.VEC];

    ClosestKnot: PROC [h: Handle, z: Complex.VEC] RETURNS [NAT];

    InitialParametricCubic: PROC [sa: ComplexSequence] RETURNS [Handle];

    ImproveParametricCubic: PROC [h: Handle, first: NAT _ 0, last: NAT _ LAST[NAT]];

    FitParametricCubic: PROC [h: Handle, first, last: NAT, epsilon: REAL];
        <<does the whole thing for a single piece>>

    ReParameterize: PROC [p: Patch, t0,t1: REAL, nt0,nt1: REAL] RETURNS[np: Patch];

    InitialParametricSpline: PROC [sa: ComplexSequence, nknots: NAT, closed: BOOLEAN _ FALSE] RETURNS [Handle];

    Sort: PROC [v: RealSequence];

    InitialTValues: PROC [h: Handle];

    AdjustTValues: PROC [h: Handle];

    FitXAndY: PROC [h: Handle];

    ImproveParametricSpline: PROC [h: Handle];

    END.