SymEngine::Derivative Class Reference

#include <functions.h>

Inheritance diagram for SymEngine::Derivative:

Collaboration diagram for SymEngine::Derivative:

Public Member Functions
void	accept (Visitor &v) const override
void	accept (EvalRealDoubleVisitorFinal &v) const override
	Derivative (const RCP< const Basic > &arg, const multiset_basic &x)
hash_t	__hash__ () const override
bool	__eq__ (const Basic &o) const override
	Test equality.
int	compare (const Basic &o) const override
RCP< const Basic >	get_arg () const
const multiset_basic &	get_symbols () const
vec_basic	get_args () const override
	Returns the list of arguments.
bool	is_canonical (const RCP< const Basic > &arg, const multiset_basic &x) const
Public Member Functions inherited from SymEngine::Basic
TypeID	get_type_code () const
	Basic ()
	Constructor.
	Basic (const Basic &)=delete
	Delete the copy constructor and assignment.
Basic &	operator= (const Basic &)=delete
	Assignment operator in continuation with above.
	Basic (Basic &&)=delete
	Delete the move constructor and assignment.
Basic &	operator= (Basic &&)=delete
	Assignment operator in continuation with above.
hash_t	hash () const
bool	__neq__ (const Basic &o) const
	true if this is not equal to o.
int	__cmp__ (const Basic &o) const
	Comparison operator.
std::string	__str__ () const
std::string	dumps () const
	Returns a string of the instance serialized.
RCP< const Basic >	subs (const map_basic_basic &subs_dict) const
	Substitutes 'subs_dict' into 'self'.
RCP< const Basic >	xreplace (const map_basic_basic &subs_dict) const
virtual RCP< const Basic >	expand_as_exp () const
	expands the special function in terms of exp function
RCP< const Basic >	diff (const RCP< const Symbol > &x, bool cache=true) const
Public Member Functions inherited from SymEngine::EnableRCPFromThis< Basic >
RCP< Basic >	rcp_from_this ()
	Get RCP<T> pointer to self (it will cast the pointer to T)
RCP< const Basic >	rcp_from_this () const
	Get RCP<const T> pointer to self (it will cast the pointer to const T)
RCP< const T2 >	rcp_from_this_cast () const
	Get RCP<T2> pointer to self (it will cast the pointer to T2)
unsigned int	use_count () const

Static Public Member Functions
static RCP< const Derivative >	create (const RCP< const Basic > &arg, const multiset_basic &x)
Static Public Member Functions inherited from SymEngine::Basic
static RCP< const Basic >	loads (const std::string &)
	Creates an instance of a serialized string.

Static Public Attributes
static const TypeID	type_code_id = SYMENGINE_DERIVATIVE
	x, y, ...

Private Attributes
RCP< const Basic >	arg_
multiset_basic	x_
	The expression to be differentiated.

Additional Inherited Members
Data Fields inherited from SymEngine::Basic
TypeID	type_code_

Detailed Description

Derivative operator Derivative(f, [x, y, ...]) represents a derivative of f with respect to x, y, and so on.

Definition at line 686 of file functions.h.

Constructor & Destructor Documentation

Derivative()

SymEngine::Derivative::Derivative	(	const RCP< const Basic > &	arg,
		const multiset_basic &	x
	)

Definition at line 1928 of file functions.cpp.

    : arg_{arg}, x_{x}
{
    SYMENGINE_ASSIGN_TYPEID()
    SYMENGINE_ASSERT(is_canonical(arg, x))
}

Member Function Documentation

__eq__()

bool SymEngine::Derivative::__eq__ ( const Basic &  o ) const

overridevirtual

Test equality.

A virtual function for testing the equality of two Basic objects

Deprecated:

Use eq(const Basic &a, const Basic &b) non-member method

Parameters

o	a constant reference to object to test against

Returns

True if this is equal to o

Implements SymEngine::Basic.

Definition at line 2008 of file functions.cpp.

{
    if (is_a<Derivative>(o)
        and eq(*arg_, *(down_cast<const Derivative &>(o).arg_))
        and unified_eq(x_, down_cast<const Derivative &>(o).x_))
        return true;
    return false;
}

__hash__()

hash_t SymEngine::Derivative::__hash__ ( ) const

overridevirtual

Calculates the hash of the given SymEngine class. Use Basic.hash() which gives a cached version of the hash.

Returns

64-bit integer value for the hash

Implements SymEngine::Basic.

Definition at line 1998 of file functions.cpp.

{
    hash_t seed = SYMENGINE_DERIVATIVE;
    hash_combine<Basic>(seed, *arg_);
    for (auto &p : x_) {
        hash_combine<Basic>(seed, *p);
    }
    return seed;
}

accept() [1/2]

void SymEngine::Derivative::accept ( EvalRealDoubleVisitorFinal &  v ) const

overridevirtual

Implements SymEngine::Basic.

accept() [2/2]

void SymEngine::Derivative::accept ( Visitor &  v ) const

overridevirtual

Implements SymEngine::Basic.

compare()

int SymEngine::Derivative::compare ( const Basic &  o ) const

overridevirtual

Returns -1, 0, 1 for this < o, this == o, this > o. This method is used when you want to sort things like x+y+z into canonical order. This function assumes that o is the same type as this. Use __cmp__ if you want general comparison.

Implements SymEngine::Basic.

Definition at line 2017 of file functions.cpp.

{
    SYMENGINE_ASSERT(is_a<Derivative>(o))
    const Derivative &s = down_cast<const Derivative &>(o);
    int cmp = arg_->__cmp__(*(s.arg_));
    if (cmp != 0)
        return cmp;
    cmp = unified_compare(x_, s.x_);
    return cmp;
}

create()

static RCP< const Derivative > SymEngine::Derivative::create ( const RCP< const Basic > &  arg, const multiset_basic &  x  )

inlinestatic

Definition at line 707 of file functions.h.

    {
        return make_rcp<const Derivative>(arg, x);
    }

get_arg()

RCP< const Basic > SymEngine::Derivative::get_arg ( ) const

inline

Definition at line 716 of file functions.h.

    {
        return arg_;
    }

get_args()

vec_basic SymEngine::Derivative::get_args ( ) const

inlineoverridevirtual

Returns the list of arguments.

Implements SymEngine::Basic.

Definition at line 724 of file functions.h.

    {
        vec_basic args = {arg_};
        args.insert(args.end(), x_.begin(), x_.end());
        return args;
    }

get_symbols()

const multiset_basic & SymEngine::Derivative::get_symbols ( ) const

inline

Definition at line 720 of file functions.h.

    {
        return x_;
    }

is_canonical()

bool SymEngine::Derivative::is_canonical	(	const RCP< const Basic > &	arg,
		const multiset_basic &	x
	)		const

Definition at line 1936 of file functions.cpp.

{
    // Check that 'x' are Symbols:
    for (const auto &a : x)
        if (not is_a<Symbol>(*a))
            return false;
    if (is_a<FunctionSymbol>(*arg) or is_a<LeviCivita>(*arg)) {
        for (auto &p : x) {
            RCP<const Symbol> s = rcp_static_cast<const Symbol>(p);
            RCP<const MultiArgFunction> f
                = rcp_static_cast<const MultiArgFunction>(arg);
            bool found_s = false;
            // 's' should be one of the args of the function
            // and should not appear anywhere else.
            for (const auto &a : f->get_args()) {
                if (eq(*a, *s)) {
                    if (found_s) {
                        return false;
                    } else {
                        found_s = true;
                    }
                } else if (neq(*a->diff(s), *zero)) {
                    return false;
                }
            }
            if (!found_s) {
                return false;
            }
        }
        return true;
    } else if (is_a<Abs>(*arg)) {
        return true;
    } else if (is_a<FunctionWrapper>(*arg)) {
        return true;
    } else if (is_a<PolyGamma>(*arg) or is_a<Zeta>(*arg)
               or is_a<UpperGamma>(*arg) or is_a<LowerGamma>(*arg)
               or is_a<Dirichlet_eta>(*arg)) {
        bool found = false;
        auto v = arg->get_args();
        for (auto &p : x) {
            if (has_symbol(*v[0], *rcp_static_cast<const Symbol>(p))) {
                found = true;
                break;
            }
        }
        return found;
    } else if (is_a<KroneckerDelta>(*arg)) {
        bool found = false;
        auto v = arg->get_args();
        for (auto &p : x) {
            if (has_symbol(*v[0], *rcp_static_cast<const Symbol>(p))
                or has_symbol(*v[1], *rcp_static_cast<const Symbol>(p))) {
                found = true;
                break;
            }
        }
        return found;
    }
    return false;
}

Field Documentation

arg_

RCP<const Basic> SymEngine::Derivative::arg_

private

Definition at line 689 of file functions.h.

type_code_id

const TypeID SymEngine::Derivative::type_code_id = SYMENGINE_DERIVATIVE

static

x, y, ...

Type_code_id shared by all instances

Definition at line 704 of file functions.h.

x_

multiset_basic SymEngine::Derivative::x_

private

The expression to be differentiated.

Definition at line 701 of file functions.h.

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

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