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build5/epsilon-master/poincare/src/hyperbolic_arc_tangent.cpp 1.49 KB
6663b6c9   adorian   projet complet av...
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  #include <poincare/hyperbolic_arc_tangent.h>
  #include <poincare/simplification_engine.h>
  #include <poincare/trigonometry.h>
  extern "C" {
  #include <assert.h>
  }
  #include <cmath>
  
  namespace Poincare {
  
  Expression::Type HyperbolicArcTangent::type() const {
    return Type::HyperbolicArcTangent;
  }
  
  Expression * HyperbolicArcTangent::clone() const {
    HyperbolicArcTangent * a = new HyperbolicArcTangent(m_operands, true);
    return a;
  }
  
  Expression * HyperbolicArcTangent::shallowReduce(Context& context, AngleUnit angleUnit) {
    Expression * e = Expression::shallowReduce(context, angleUnit);
    if (e != this) {
      return e;
    }
  #if MATRIX_EXACT_REDUCING
    Expression * op = editableOperand(0);
    if (op->type() == Type::Matrix) {
      return SimplificationEngine::map(this, context, angleUnit);
    }
  #endif
    return this;
  }
  
  template<typename T>
  std::complex<T> HyperbolicArcTangent::computeOnComplex(const std::complex<T> c, AngleUnit angleUnit) {
    std::complex<T> result = std::atanh(c);
    /* atanh has a branch cut on ]-inf, -1[U]1, +inf[: it is then multivalued on
     * this cut. We followed the convention chosen by the lib c++ of llvm on
     * ]-inf+0i, -1+0i[ (warning: atanh takes the other side of the cut values on
     * ]-inf-0i, -1-0i[) and choose the values on ]1+0i, +inf+0i[ to comply with
     * atanh(-x) = -atanh(x) and sin(artanh(x)) = x/sqrt(1-x^2). */
    if (c.imag() == 0 && c.real() > 1) {
      result.imag(-result.imag()); // other side of the cut
    }
    return Trigonometry::RoundToMeaningfulDigits(result);
  }
  
  }