SymEngine::PositiveVisitor Class Reference

Inheritance diagram for SymEngine::PositiveVisitor:

Collaboration diagram for SymEngine::PositiveVisitor:

Public Member Functions
	PositiveVisitor (const Assumptions *assumptions)
void	bvisit (const Symbol &x)
void	bvisit (const Number &x)
void	bvisit (const Constant &x)
void	bvisit (const Add &x)
void	bvisit (const Basic &x)
void	bvisit (const Set &x)
void	bvisit (const Relational &x)
void	bvisit (const Boolean &x)
tribool	apply (const Basic &b)

Private Member Functions
void	error ()

Private Attributes
tribool	is_positive_
const Assumptions *	assumptions_

Detailed Description

Definition at line 35 of file test_visitors.h.

Constructor & Destructor Documentation

PositiveVisitor()

SymEngine::PositiveVisitor::PositiveVisitor ( const Assumptions *  assumptions )

inline

Definition at line 44 of file test_visitors.h.

        : assumptions_(assumptions){};

Member Function Documentation

apply()

tribool SymEngine::PositiveVisitor::apply

(

const Basic &

b

)

Definition at line 189 of file test_visitors.cpp.

{
    b.accept(*this);
    return is_positive_;
}

bvisit() [1/8]

void SymEngine::PositiveVisitor::bvisit

(

const Add &

x

)

Definition at line 144 of file test_visitors.cpp.

{
    // True if all are positive
    // False if all are negative
    auto coef = x.get_coef();
    auto dict = x.get_dict();
 
    bool can_be_true = true;
    bool can_be_false = true;
    if (coef->is_positive()) {
        can_be_false = false;
    } else if (coef->is_negative()) {
        can_be_true = false;
    }
    NegativeVisitor neg_visitor(assumptions_);
    for (const auto &p : dict) {
        if (not can_be_true and not can_be_false) {
            is_positive_ = tribool::indeterminate;
            return;
        }
        p.first->accept(*this);
        if ((p.second->is_positive() and is_true(is_positive_))
            or (p.second->is_negative()
                and is_true(neg_visitor.apply(*p.first)))) {
            // key * value is positive
            can_be_false = false;
        } else if ((p.second->is_negative() and is_true(is_positive_))
                   or (p.second->is_positive()
                       and is_true(neg_visitor.apply(*p.first)))) {
            // key * value is negative
            can_be_true = false;
        } else {
            can_be_true = false;
            can_be_false = false;
        }
    }
    if (can_be_true) {
        is_positive_ = tribool::tritrue;
    } else if (can_be_false) {
        is_positive_ = tribool::trifalse;
    } else {
        is_positive_ = tribool::indeterminate;
    }
}

bvisit() [2/8]

void SymEngine::PositiveVisitor::bvisit

(

const Basic &

x

)

Definition at line 104 of file test_visitors.cpp.

{
    is_positive_ = tribool::indeterminate;
}

bvisit() [3/8]

void SymEngine::PositiveVisitor::bvisit

(

const Boolean &

x

)

Definition at line 119 of file test_visitors.cpp.

{
    error();
}

bvisit() [4/8]

void SymEngine::PositiveVisitor::bvisit

(

const Constant &

x

)

Definition at line 99 of file test_visitors.cpp.

{
    is_positive_ = tribool::tritrue;
}

bvisit() [5/8]

void SymEngine::PositiveVisitor::bvisit

(

const Number &

x

)

Definition at line 133 of file test_visitors.cpp.

{
    if (is_a_Complex(x)) {
        is_positive_ = tribool::trifalse;
    } else if (bool(x.is_positive())) {
        is_positive_ = tribool::tritrue;
    } else {
        is_positive_ = tribool::trifalse;
    }
}

bvisit() [6/8]

void SymEngine::PositiveVisitor::bvisit

(

const Relational &

x

)

Definition at line 114 of file test_visitors.cpp.

{
    error();
}

bvisit() [7/8]

void SymEngine::PositiveVisitor::bvisit

(

const Set &

x

)

Definition at line 109 of file test_visitors.cpp.

{
    error();
}

bvisit() [8/8]

void SymEngine::PositiveVisitor::bvisit

(

const Symbol &

x

)

Definition at line 124 of file test_visitors.cpp.

{
    if (assumptions_) {
        is_positive_ = assumptions_->is_positive(x.rcp_from_this());
    } else {
        is_positive_ = tribool::indeterminate;
    }
}

error()

void SymEngine::PositiveVisitor::error ( )

private

Definition at line 94 of file test_visitors.cpp.

{
    throw SymEngineException("Only numeric types allowed for is_positive");
}

Field Documentation

assumptions_

const Assumptions* SymEngine::PositiveVisitor::assumptions_

private

Definition at line 39 of file test_visitors.h.

is_positive_

tribool SymEngine::PositiveVisitor::is_positive_

private

Definition at line 38 of file test_visitors.h.

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The documentation for this class was generated from the following files:

• /home/runner/work/symengine/symengine/symengine/test_visitors.h
• /home/runner/work/symengine/symengine/symengine/test_visitors.cpp