1 // Created on: 1991-05-27
2 // Created by: Arnaud BOUZY
3 // Copyright (c) 1991-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
6 // This file is part of Open CASCADE Technology software library.
8 // This library is free software; you can redistribute it and/or modify it under
9 // the terms of the GNU Lesser General Public License version 2.1 as published
10 // by the Free Software Foundation, with special exception defined in the file
11 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 // distribution for complete text of the license and disclaimer of any warranty.
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
19 #include <Expr_ArcCosine.hxx>
20 #include <Expr_Cosine.hxx>
21 #include <Expr_Difference.hxx>
22 #include <Expr_Division.hxx>
23 #include <Expr_GeneralExpression.hxx>
24 #include <Expr_NamedUnknown.hxx>
25 #include <Expr_NotEvaluable.hxx>
26 #include <Expr_NumericValue.hxx>
27 #include <Expr_Operators.hxx>
28 #include <Expr_Product.hxx>
29 #include <Expr_Square.hxx>
30 #include <Expr_SquareRoot.hxx>
31 #include <Expr_UnaryMinus.hxx>
32 #include <Standard_NumericError.hxx>
33 #include <Standard_Type.hxx>
34 #include <TCollection_AsciiString.hxx>
36 IMPLEMENT_STANDARD_RTTIEXT(Expr_ArcCosine,Expr_UnaryExpression)
38 Expr_ArcCosine::Expr_ArcCosine (const Handle(Expr_GeneralExpression)& exp)
43 Handle(Expr_GeneralExpression) Expr_ArcCosine::ShallowSimplified () const
45 Handle(Expr_GeneralExpression) op = Operand();
46 if (op->IsKind(STANDARD_TYPE(Expr_NumericValue))) {
47 Handle(Expr_NumericValue) valop = Handle(Expr_NumericValue)::DownCast(op);
48 return new Expr_NumericValue(ACos(valop->GetValue()));
50 if (op->IsKind(STANDARD_TYPE(Expr_Cosine))) {
51 return op->SubExpression(1);
53 Handle(Expr_ArcCosine) me = this;
57 Handle(Expr_GeneralExpression) Expr_ArcCosine::Copy () const
59 return new Expr_ArcCosine(Expr::CopyShare(Operand()));
62 Standard_Boolean Expr_ArcCosine::IsIdentical (const Handle(Expr_GeneralExpression)& Other) const
64 if (!Other->IsKind(STANDARD_TYPE(Expr_ArcCosine))) {
65 return Standard_False;
67 Handle(Expr_GeneralExpression) op = Operand();
68 return op->IsIdentical(Other->SubExpression(1));
71 Standard_Boolean Expr_ArcCosine::IsLinear () const
73 if (ContainsUnknowns()) {
74 return Standard_False;
79 Handle(Expr_GeneralExpression) Expr_ArcCosine::Derivative (const Handle(Expr_NamedUnknown)& X) const
82 return new Expr_NumericValue(0.0);
84 Handle(Expr_GeneralExpression) op = Operand();
85 Handle(Expr_GeneralExpression) derop = op->Derivative(X);
87 Handle(Expr_Square) sq = new Expr_Square(Expr::CopyShare(op));
89 Handle(Expr_Difference) thedif = 1.0 - sq->ShallowSimplified();
91 Handle(Expr_SquareRoot) theroot = new Expr_SquareRoot(thedif->ShallowSimplified());
93 Handle(Expr_UnaryMinus) theder = - (1.0 / theroot->ShallowSimplified());
95 // ArcCosine'(F(X)) = -1/sqrt(1-F(X)2) * F'(X)
97 Handle(Expr_Product) result = theder->ShallowSimplified() * derop;
99 return result->ShallowSimplified();
102 Standard_Real Expr_ArcCosine::Evaluate(const Expr_Array1OfNamedUnknown& vars, const TColStd_Array1OfReal& vals) const
104 return ::ACos(Operand()->Evaluate(vars,vals));
107 TCollection_AsciiString Expr_ArcCosine::String() const
109 TCollection_AsciiString str("ACos(");
110 str += Operand()->String();