Package sage :: Package calculus :: Module calculus :: Class SymbolicFunction
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Class SymbolicFunction

source code

                      object --+                        
                               |                        
structure.sage_object.SageObject --+                    
                                   |                    
           structure.element.Element --+                
                                       |                
         structure.element.ModuleElement --+            
                                           |            
               structure.element.RingElement --+        
                                               |        
                              SymbolicExpression --+    
                                                   |    
                                   PrimitiveFunction --+
                                                       |
                                                      SymbolicFunction
Known Subclasses:
SymbolicFunction_delayed


A formal symbolic function.

EXAMPLES:
    sage: f = function('foo')
    sage: var('x,y,z')
    (x, y, z)
    sage: g = f(x,y,z)
    sage: g
    foo(x, y, z)
    sage: g(x=var('theta'))
    foo(theta, y, z)



Instance Methods [hide private]
 
__init__(self, name)
Create a symbolic expression.
source code
 
__hash__(self)
Returns the hash of this symbolic expression.
source code
 
_repr_(self, simplify=True)
File: sage/structure/element.pyx (starting at line 291)
source code
 
_is_atomic(self)
File: sage/structure/element.pyx (starting at line 497) Return True if and only if parenthesis are not required when *printing* out any of $x - s$, $x + s$, $x^s$ and $x/s$.
source code
 
_latex_(self) source code
 
_maxima_init_(self)
File: sage/structure/sage_object.pyx (starting at line 318)
source code
 
_approx_(self, x) source code
 
__call__(self, *args)
EXAMPLES: sage: x,y=var('x,y') sage: f = x+y sage: f.arguments() (x, y) sage: f() y + x sage: f(3) y + 3 sage: f(3,4) 7 sage: f(2,3,4) Traceback (most recent call last): ...
source code

Inherited from PrimitiveFunction: _complex_approx_, number_of_arguments, plot, tex_needs_braces

Inherited from SymbolicExpression: __abs__, __cmp__, __eq__, __ge__, __gt__, __int__, __le__, __long__, __lt__, __ne__, __nonzero__, __pow__, __str__, _add_, _axiom_init_, _complex_double_, _complex_mpfr_field_, _div_, _fast_float_, _gap_init_, _gp_init_, _integer_, _kash_init_, _macaulay2_init_, _magma_init_, _maple_init_, _mathematica_init_, _maxima_, _mpfr_, _mul_, _neg_, _octave_init_, _pari_init_, _polynomial_, _rational_, _real_double_, _real_rqdf_, _richcmp_, _singular_init_, _sub_, _sys_init_, arguments, coeff, coefficient, coefficients, coeffs, combine, conjugate, default_variable, denominator, derivative, diff, differentiate, display2d, exp_simplify, expand, expand_rational, expand_trig, factor, factor_list, find_maximum_on_interval, find_minimum_on_interval, find_root, full_simplify, function, gradient, hessian, imag, integral, integrate, inverse_laplace, laplace, limit, log_simplify, minpoly, n, nintegral, nintegrate, norm, numerator, numerical_approx, partial_fraction, poly, polynomial, power_series, radical_simplify, rational_expand, rational_simplify, real, roots, show, simplify, simplify_exp, simplify_full, simplify_log, simplify_radical, simplify_rational, simplify_trig, solve, subs, subs_expr, substitute, substitute_over_ring, taylor, trig_expand, trig_simplify, variables

Inherited from structure.element.RingElement: __div__, __idiv__, __imul__, __invert__, __mul__, __new__, __pos__, __rdiv__, __rmul__, __rpow__, __rtruediv__, __truediv__, _idiv_, _imul_, abs, additive_order, is_nilpotent, is_one, is_unit, multiplicative_order, order

Inherited from structure.element.ModuleElement: __add__, __iadd__, __isub__, __neg__, __radd__, __rsub__, __sub__, _iadd_, _ilmul_, _isub_, _lmul_, _rmul_

Inherited from structure.element.Element: __reduce__, __rxor__, __xor__, _cmp_, _im_gens_, base_base_extend, base_base_extend_canonical_sym, base_extend, base_extend_canonical, base_extend_canonical_sym, base_extend_recursive, base_ring, category, is_zero, parent

Inherited from structure.sage_object.SageObject: __repr__, _axiom_, _gap_, _gp_, _interface_, _interface_init_, _interface_is_cached_, _kash_, _macaulay2_, _magma_, _maple_, _mathematica_, _octave_, _pari_, _r_init_, _sage_, _singular_, db, dump, dumps, rename, reset_name, save, version

Inherited from object: __delattr__, __getattribute__, __reduce_ex__, __setattr__

Properties [hide private]

Inherited from object: __class__

Method Details [hide private]

__init__(self, name)
(Constructor)

source code 

Create a symbolic expression.

EXAMPLES:
This example is mainly for testing purposes.

We explicitly import the SymbolicExpression class.
    sage: from sage.calculus.calculus import SymbolicExpression

Then we make an instance of it.  Note that it prints as a
``generic element'', since it doesn't even have a specific
value!
    sage: a = SymbolicExpression(); a
    Generic element of a structure

It's of the right type.
    sage: type(a)
    <class 'sage.calculus.calculus.SymbolicExpression'>

And it has the right parent. 
    sage: a.parent()
    Symbolic Ring        

Overrides: PrimitiveFunction.__init__

__hash__(self)
(Hashing function)

source code 

Returns the hash of this symbolic expression.

EXAMPLES:
We hash a symbolic polynomial:
    sage: hash(x^2 + 1) #random due to architecture dependence
    -832266011

The default hashing strategy is to simply hash
the string representation of an object.
    sage: hash(repr(x^2+1)) #random due to architecture dependence
    -832266011

In some cases a better hashing strategy is used.
    sage: hash(SR(3/1)) 
    3
    sage: hash(repr(SR(3/1))) #random due to architecture dependence
    -2061914958        

Overrides: SymbolicExpression.__hash__
(inherited documentation)

_repr_(self, simplify=True)

source code 
File: sage/structure/element.pyx (starting at line 291)

Overrides: structure.element.Element._repr_
(inherited documentation)

_is_atomic(self)

source code 
File: sage/structure/element.pyx (starting at line 497)

Return True if and only if parenthesis are not required when
*printing* out any of $x - s$, $x + s$, $x^s$ and $x/s$.

EXAMPLES:
    sage: n = 5; n._is_atomic()
    True
    sage: n = x+1; n._is_atomic()
    False

Overrides: PrimitiveFunction._is_atomic

_maxima_init_(self)

source code 
File: sage/structure/sage_object.pyx (starting at line 318)

Overrides: SymbolicExpression._maxima_init_

_approx_(self, x)

source code 
Overrides: PrimitiveFunction._approx_

__call__(self, *args)
(Call operator)

source code 

EXAMPLES:
    sage: x,y=var('x,y')
    sage: f = x+y
    sage: f.arguments()
    (x, y)
    sage: f()
    y + x
    sage: f(3)
    y + 3
    sage: f(3,4)
    7
    sage: f(2,3,4)
    Traceback (most recent call last):
    ...
    ValueError: the number of arguments must be less than or equal to 2

    sage: f({x:3})
    y + 3
    sage: f({x:3,y:4})
    7
    sage: f(x=3)
    y + 3
    sage: f(x=3,y=4)
    7

    sage: a = (2^(8/9))
    sage: a(4)
    Traceback (most recent call last):
    ...
    ValueError: the number of arguments must be less than or equal to 0


    sage: f = function('Gamma', var('z'), var('w')); f
    Gamma(z, w)
    sage: f(2)
    Gamma(2, w)
    sage: f(2,5)
    Gamma(2, 5)

Overrides: PrimitiveFunction.__call__