See the Printing section in Tutorial for introduction into printing.
This guide documents the printing system in SymPy and how it works internally.
Printing subsystem driver
SymPy’s printing system works the following way: Any expression can be passed to a designated Printer who then is responsible to return an adequate representation of that expression.
Some more information how the single concepts work and who should use which:
The object prints itself
This was the original way of doing printing in sympy. Every class had its own latex, mathml, str and repr methods, but it turned out that it is hard to produce a high quality printer, if all the methods are spread out that far. Therefor all printing code was combined into the different printers, which works great for built-in sympy objects, but not that good for user defined classes where it is inconvenient to patch the printers.
Nevertheless, to get a fitting representation, the printers look for a specific method in every object, that will be called if it’s available and is then responsible for the representation. The name of that method depends on the specific printer and is defined under Printer.printmethod.
Take the best fitting method defined in the printer.
The printer loops through expr classes (class + its bases), and tries to dispatch the work to _print_<EXPR_CLASS>
e.g., suppose we have the following class hierarchy:
Basic | Atom | Number | Rationalthen, for expr=Rational(...), in order to dispatch, we will try calling printer methods as shown in the figure below:
p._print(expr) | |-- p._print_Rational(expr) | |-- p._print_Number(expr) | |-- p._print_Atom(expr) | `-- p._print_Basic(expr)if ._print_Rational method exists in the printer, then it is called, and the result is returned back.
otherwise, we proceed with trying Rational bases in the inheritance order.
As fall-back use the emptyPrinter method for the printer.
As fall-back self.emptyPrinter will be called with the expression. If not defined in the Printer subclass this will be the same as str(expr).
The main class responsible for printing is Printer (see also its source code):
Generic printer
Its job is to provide infrastructure for implementing new printers easily.
Basically, if you want to implement a printer, all you have to do is:
Subclass Printer.
Define Printer.printmethod in your subclass. If a object has a method with that name, this method will be used for printing.
In your subclass, define _print_<CLASS> methods
For each class you want to provide printing to, define an appropriate method how to do it. For example if you want a class FOO to be printed in its own way, define _print_FOO:
def _print_FOO(self, e):
...
this should return how FOO instance e is printed
Also, if BAR is a subclass of FOO, _print_FOO(bar) will be called for instance of BAR, if no _print_BAR is provided. Thus, usually, we don’t need to provide printing routines for every class we want to support – only generic routine has to be provided for a set of classes.
A good example for this are functions - for example PrettyPrinter only defines _print_Function, and there is no _print_sin, _print_tan, etc...
On the other hand, a good printer will probably have to define separate routines for Symbol, Atom, Number, Integral, Limit, etc...
If convenient, override self.emptyPrinter
This callable will be called to obtain printing result as a last resort, that is when no appropriate print method was found for an expression.
Examples of overloading StrPrinter:
from sympy import Basic, Function, Symbol
from sympy.printing.str import StrPrinter
class CustomStrPrinter(StrPrinter):
"""
Examples of how to customize the StrPrinter for both a SymPy class and a
user defined class subclassed from the SymPy Basic class.
"""
def _print_Derivative(self, expr):
"""
Custom printing of the SymPy Derivative class.
Instead of:
D(x(t), t) or D(x(t), t, t)
We will print:
x' or x''
In this example, expr.args == (x(t), t), and expr.args[0] == x(t), and
expr.args[0].func == x
"""
return str(expr.args[0].func) + "'"*len(expr.args[1:])
def _print_MyClass(self, expr):
"""
Print the characters of MyClass.s alternatively lower case and upper
case
"""
s = ""
i = 0
for char in expr.s:
if i % 2 == 0:
s += char.lower()
else:
s += char.upper()
i += 1
return s
# Override the __str__ method of to use CustromStrPrinter
Basic.__str__ = lambda self: CustomStrPrinter().doprint(self)
# Demonstration of CustomStrPrinter:
t = Symbol('t')
x = Function('x')(t)
dxdt = x.diff(t) # dxdt is a Derivative instance
d2xdt2 = dxdt.diff(t) # dxdt2 is a Derivative instance
ex = MyClass('I like both lowercase and upper case')
print dxdt
print d2xdt2
print ex
The output of the above code is:
x'
x''
i lIkE BoTh lOwErCaSe aNd uPpEr cAsE
By overriding Basic.__str__, we can customize the printing of anything that is subclassed from Basic.
Attributes
| printmethod |
Internal dispatcher
Returns printer’s representation for expr (as a string)
Set system-wide printing settings.
The pretty printing subsystem is implemented in sympy.printing.pretty.pretty by the PrettyPrinter class deriving from Printer. It relies on the modules sympy.printing.pretty.stringPict, and sympy.printing.pretty.pretty_symbology for rendering nice-looking formulas.
The module stringPict provides a base class stringPict and a derived class prettyForm that ease the creation and manipulation of formulas that span across multiple lines.
The module pretty_symbology provides primitives to construct 2D shapes (hline, vline, etc) together with a technique to use unicode automatically when possible.
Printer, which converts an expression into 2D ASCII-art figure.
Returns a string containing the prettified form of expr.
For information on keyword arguments see pretty_print function.
Prints expr in pretty form.
pprint is just a shortcut for this function.
| Parameters: | expr : expression
wrap_line : bool, optional
num_columns : int or None, optional
use_unicode : bool or None, optional
full_prec : bool or string, optional
order : bool or string, optional
|
|---|
This class implements C code printing (i.e. it converts Python expressions to strings of C code).
Usage:
>>> from sympy.printing import print_ccode
>>> from sympy.functions import sin, cos, Abs
>>> from sympy.abc import x
>>> print_ccode(sin(x)**2 + cos(x)**2)
pow(sin(x), 2) + pow(cos(x), 2)
>>> print_ccode(2*x + cos(x), assign_to="result")
result = 2*x + cos(x);
>>> print_ccode(Abs(x**2))
fabs(pow(x, 2))
A printer to convert python expressions to strings of c code
Actually format the expression as C code.
Accepts a string of code or a list of code lines
Converts an expr to a string of c code
| Parameters: | expr : sympy.core.Expr
precision : optional
user_functions : optional
human : optional
|
|---|
Examples
>>> from sympy import ccode, symbols, Rational, sin, ceiling, Abs
>>> x, tau = symbols(["x", "tau"])
>>> ccode((2*tau)**Rational(7,2))
'8*sqrt(2)*pow(tau, 7.0L/2.0L)'
>>> ccode(sin(x), assign_to="s")
's = sin(x);'
>>> custom_functions = {
... "ceiling": "CEIL",
... "Abs": [(lambda x: not x.is_integer, "fabs"),
... (lambda x: x.is_integer, "ABS")]
... }
>>> ccode(Abs(x) + ceiling(x), user_functions=custom_functions)
'fabs(x) + CEIL(x)'
Prints C representation of the given expression.
The fcode function translates a sympy expression into Fortran code. The main purpose is to take away the burden of manually translating long mathematical expressions. Therefore the resulting expression should also require no (or very little) manual tweaking to make it compilable. The optional arguments of fcode can be used to fine-tune the behavior of fcode in such a way that manual changes in the result are no longer needed.
Converts an expr to a string of Fortran 77 code
| Parameters: | expr : sympy.core.Expr
assign_to : optional
precision : optional
user_functions : optional
human : optional
source_format : optional
|
|---|
Examples
>>> from sympy import fcode, symbols, Rational, pi, sin
>>> x, tau = symbols('x,tau')
>>> fcode((2*tau)**Rational(7,2))
' 8*sqrt(2.0d0)*tau**(7.0d0/2.0d0)'
>>> fcode(sin(x), assign_to="s")
' s = sin(x)'
>>> print(fcode(pi))
parameter (pi = 3.14159265358979d0)
pi
Prints the Fortran representation of the given expression.
See fcode for the meaning of the optional arguments.
A printer to convert sympy expressions to strings of Fortran code
Returns Fortran code for expr (as a string)
Accepts a string of code or a list of code lines
Two basic examples:
>>> from sympy import *
>>> x = symbols("x")
>>> fcode(sqrt(1-x**2))
' sqrt(-x**2 + 1)'
>>> fcode((3 + 4*I)/(1 - conjugate(x)))
' (cmplx(3,4))/(-conjg(x) + 1)'
An example where line wrapping is required:
>>> expr = sqrt(1-x**2).series(x,n=20).removeO()
>>> print(fcode(expr))
-715.0d0/65536.0d0*x**18 - 429.0d0/32768.0d0*x**16 - 33.0d0/
@ 2048.0d0*x**14 - 21.0d0/1024.0d0*x**12 - 7.0d0/256.0d0*x**10 -
@ 5.0d0/128.0d0*x**8 - 1.0d0/16.0d0*x**6 - 1.0d0/8.0d0*x**4 - 1.0d0
@ /2.0d0*x**2 + 1
In case of line wrapping, it is handy to include the assignment so that lines are wrapped properly when the assignment part is added.
>>> print(fcode(expr, assign_to="var"))
var = -715.0d0/65536.0d0*x**18 - 429.0d0/32768.0d0*x**16 - 33.0d0/
@ 2048.0d0*x**14 - 21.0d0/1024.0d0*x**12 - 7.0d0/256.0d0*x**10 -
@ 5.0d0/128.0d0*x**8 - 1.0d0/16.0d0*x**6 - 1.0d0/8.0d0*x**4 - 1.0d0
@ /2.0d0*x**2 + 1
For piecewise functions, the assign_to option is mandatory:
>>> print(fcode(Piecewise((x,x<1),(x**2,True)), assign_to="var"))
if (x < 1) then
var = x
else
var = x**2
end if
Note that only top-level piecewise functions are supported due to the lack of a conditional operator in Fortran. Nested piecewise functions would require the introduction of temporary variables, which is a type of expression manipulation that goes beyond the scope of fcode.
Loops are generated if there are Indexed objects in the expression. This also requires use of the assign_to option.
>>> A, B = map(IndexedBase, ['A', 'B'])
>>> m = Symbol('m', integer=True)
>>> i = Idx('i', m)
>>> print(fcode(2*B[i], assign_to=A[i]))
do i = 1, m
A(i) = 2*B(i)
end do
Repeated indices in an expression with Indexed objects are interpreted as summation. For instance, code for the trace of a matrix can be generated with
>>> print(fcode(A[i, i], assign_to=x))
x = 0
do i = 1, m
x = x + A(i, i)
end do
By default, number symbols such as pi and E are detected and defined as Fortran parameters. The precision of the constants can be tuned with the precision argument. Parameter definitions are easily avoided using the N function.
>>> print(fcode(x - pi**2 - E))
parameter (E = 2.71828182845905d0)
parameter (pi = 3.14159265358979d0)
x - pi**2 - E
>>> print(fcode(x - pi**2 - E, precision=25))
parameter (E = 2.718281828459045235360287d0)
parameter (pi = 3.141592653589793238462643d0)
x - pi**2 - E
>>> print(fcode(N(x - pi**2, 25)))
x - 9.869604401089358618834491d0
When some functions are not part of the Fortran standard, it might be desirable to introduce the names of user-defined functions in the Fortran expression.
>>> print(fcode(1 - gamma(x)**2, user_functions={gamma: 'mygamma'}))
-mygamma(x)**2 + 1
However, when the user_functions argument is not provided, fcode attempts to use a reasonable default and adds a comment to inform the user of the issue.
>>> print(fcode(1 - gamma(x)**2))
C Not Fortran:
C gamma(x)
-gamma(x)**2 + 1
By default the output is human readable code, ready for copy and paste. With the option human=False, the return value is suitable for post-processing with source code generators that write routines with multiple instructions. The return value is a three-tuple containing: (i) a set of number symbols that must be defined as ‘Fortran parameters’, (ii) a list functions that can not be translated in pure Fortran and (iii) a string of Fortran code. A few examples:
>>> fcode(1 - gamma(x)**2, human=False)
(set(), set([gamma(x)]), ' -gamma(x)**2 + 1')
>>> fcode(1 - sin(x)**2, human=False)
(set(), set(), ' -sin(x)**2 + 1')
>>> fcode(x - pi**2, human=False)
(set([(pi, '3.14159265358979d0')]), set(), ' x - pi**2')
You can print to a grkmathview widget using the function print_gtk located in sympy.printing.gtk (it requires to have installed gtkmatmatview and libgtkmathview-bin in some systems).
GtkMathView accepts MathML, so this rendering depends on the MathML representation of the expression.
Usage:
from sympy import *
print_gtk(x**2 + 2*exp(x**3))
Print to Gtkmathview, a gtk widget capable of rendering MathML.
Needs libgtkmathview-bin
This classes implements printing to strings that can be used by the sympy.utilities.lambdify.lambdify() function.
This printer converts expressions into strings that can be used by lambdify.
Returns a string usable for lambdifying.
This class implements LaTeX printing. See sympy.printing.latex.
list() -> new empty list list(iterable) -> new list initialized from iterable’s items
Convert the given expression to LaTeX representation.
>>> from sympy import latex, pi, sin, asin, Integral, Matrix, Rational
>>> from sympy.abc import x, y, mu, r, tau
>>> print(latex((2*tau)**Rational(7,2)))
8 \sqrt{2} \tau^{\frac{7}{2}}
order: Any of the supported monomial orderings (currently “lex”, “grlex”, or “grevlex”), “old”, and “none”. This parameter does nothing for Mul objects. Setting order to “old” uses the compatibility ordering for Add defined in Printer. For very large expressions, set the ‘order’ keyword to ‘none’ if speed is a concern.
mode: Specifies how the generated code will be delimited. ‘mode’ can be one of ‘plain’, ‘inline’, ‘equation’ or ‘equation*’. If ‘mode’ is set to ‘plain’, then the resulting code will not be delimited at all (this is the default). If ‘mode’ is set to ‘inline’ then inline LaTeX $ $ will be used. If ‘mode’ is set to ‘equation’ or ‘equation*’, the resulting code will be enclosed in the ‘equation’ or ‘equation*’ environment (remember to import ‘amsmath’ for ‘equation*’), unless the ‘itex’ option is set. In the latter case, the $$ $$ syntax is used.
>>> print(latex((2*mu)**Rational(7,2), mode='plain'))
8 \sqrt{2} \mu^{\frac{7}{2}}
>>> print(latex((2*tau)**Rational(7,2), mode='inline'))
$8 \sqrt{2} \tau^{\frac{7}{2}}$
>>> print(latex((2*mu)**Rational(7,2), mode='equation*'))
\begin{equation*}8 \sqrt{2} \mu^{\frac{7}{2}}\end{equation*}
>>> print(latex((2*mu)**Rational(7,2), mode='equation'))
\begin{equation}8 \sqrt{2} \mu^{\frac{7}{2}}\end{equation}
itex: Specifies if itex-specific syntax is used, including emitting $$ $$.
>>> print(latex((2*mu)**Rational(7,2), mode='equation', itex=True))
$$8 \sqrt{2} \mu^{\frac{7}{2}}$$
fold_frac_powers: Emit “^{p/q}” instead of “^{frac{p}{q}}” for fractional powers.
>>> print(latex((2*tau)**Rational(7,2), fold_frac_powers=True))
8 \sqrt{2} \tau^{7/2}
fold_func_brackets: Fold function brackets where applicable.
>>> print(latex((2*tau)**sin(Rational(7,2))))
\left(2 \tau\right)^{\sin{\left (\frac{7}{2} \right )}}
>>> print(latex((2*tau)**sin(Rational(7,2)), fold_func_brackets = True))
\left(2 \tau\right)^{\sin {\frac{7}{2}}}
fold_short_frac: Emit “p / q” instead of “frac{p}{q}” when the denominator is simple enough (at most two terms and no powers). The default value is \(True\) for inline mode, False otherwise.
>>> print(latex(3*x**2/y))
\frac{3 x^{2}}{y}
>>> print(latex(3*x**2/y, fold_short_frac=True))
3 x^{2} / y
long_frac_ratio: The allowed ratio of the width of the numerator to the width of the denominator before we start breaking off long fractions. The default value is 2.
>>> print(latex(Integral(r, r)/2/pi, long_frac_ratio=2))
\frac{\int r\, dr}{2 \pi}
>>> print(latex(Integral(r, r)/2/pi, long_frac_ratio=0))
\frac{1}{2 \pi} \int r\, dr
mul_symbol: The symbol to use for multiplication. Can be one of None, “ldot”, “dot”, or “times”.
>>> print(latex((2*tau)**sin(Rational(7,2)), mul_symbol="times"))
\left(2 \times \tau\right)^{\sin{\left (\frac{7}{2} \right )}}
inv_trig_style: How inverse trig functions should be displayed. Can be one of “abbreviated”, “full”, or “power”. Defaults to “abbreviated”.
>>> print(latex(asin(Rational(7,2))))
\operatorname{asin}{\left (\frac{7}{2} \right )}
>>> print(latex(asin(Rational(7,2)), inv_trig_style="full"))
\arcsin{\left (\frac{7}{2} \right )}
>>> print(latex(asin(Rational(7,2)), inv_trig_style="power"))
\sin^{-1}{\left (\frac{7}{2} \right )}
mat_str: Which matrix environment string to emit. “smallmatrix”, “matrix”, “array”, etc. Defaults to “smallmatrix” for inline mode, “matrix” for matrices of no more than 10 columns, and “array” otherwise.
>>> print(latex(Matrix(2, 1, [x, y])))
\left[\begin{matrix}x\\y\end{matrix}\right]
>>> print(latex(Matrix(2, 1, [x, y]), mat_str = "array"))
\left[\begin{array}{c}x\\y\end{array}\right]
mat_delim: The delimiter to wrap around matrices. Can be one of “[”, “(”, or the empty string. Defaults to “[”.
>>> print(latex(Matrix(2, 1, [x, y]), mat_delim="("))
\left(\begin{matrix}x\\y\end{matrix}\right)
symbol_names: Dictionary of symbols and the custom strings they should be emitted as.
>>> print(latex(x**2, symbol_names={x:'x_i'}))
x_i^{2}
Besides all Basic based expressions, you can recursively convert Python containers (lists, tuples and dicts) and also SymPy matrices:
>>> print(latex([2/x, y], mode='inline'))
$\begin{bmatrix}2 / x, & y\end{bmatrix}$
Prints LaTeX representation of the given expression.
This class is responsible for MathML printing. See sympy.printing.mathml.
More info on mathml content: http://www.w3.org/TR/MathML2/chapter4.html
Prints an expression to the MathML markup language
Whenever possible tries to use Content markup and not Presentation markup.
References: http://www.w3.org/TR/MathML2/
Prints the expression as MathML.
Returns the MathML tag for an expression.
Returns the MathML representation of expr
Prints a pretty representation of the MathML code for expr
Examples
>>> ##
>>> from sympy.printing.mathml import print_mathml
>>> from sympy.abc import x
>>> print_mathml(x+1)
<apply>
<plus/>
<ci>x</ci>
<cn>1</cn>
</apply>
This class implements Python printing. Usage:
>>> from sympy import print_python, sin
>>> from sympy.abc import x
>>> print_python(5*x**3 + sin(x))
x = Symbol('x')
e = 5*x**3 + sin(x)
This printer generates executable code. This code satisfies the identity eval(srepr(expr)) == expr.
The fallback printer.
Prints each item in \(args\) and joins them with \(sep\).
return expr in repr form
This module generates readable representations of SymPy expressions.
return expr in mixed str/repr form
i.e. strings are returned in repr form with quotes, and everything else is returned in str form.
This function could be useful for hooking into sys.displayhook
The functions in this module create a representation of an expression as a tree.
Prettyprints systems of nodes.
Examples
>>> from sympy.printing.tree import pprint_nodes
>>> print(pprint_nodes(["a", "b1\nb2", "c"]))
+-a
+-b1
| b2
+-c
Returns an information about the “node”.
This includes class name, string representation and assumptions.
Returns a tree representation of “node” as a string.
It uses print_node() together with pprint_nodes() on node.args recursively.
See also: print_tree()
Prints a tree representation of “node”.
Examples
>>> from sympy.printing import print_tree
>>> from sympy.abc import x
>>> print_tree(x**2)
Pow: x**2
+-Symbol: x
| comparable: False
+-Integer: 2
real: True
nonzero: True
comparable: True
commutative: True
infinitesimal: False
unbounded: False
noninteger: False
zero: False
complex: True
bounded: True
rational: True
integer: True
imaginary: False
finite: True
irrational: False
See also: tree()
A useful function is preview:
View expression or LaTeX markup in PNG, DVI, PostScript or PDF form.
If the expr argument is an expression, it will be exported to LaTeX and then compiled using the available TeX distribution. The first argument, ‘expr’, may also be a LaTeX string. The function will then run the appropriate viewer for the given output format or use the user defined one. By default png output is generated.
By default pretty Euler fonts are used for typesetting (they were used to typeset the well known “Concrete Mathematics” book). For that to work, you need the ‘eulervm.sty’ LaTeX style (in Debian/Ubuntu, install the texlive-fonts-extra package). If you prefer default AMS fonts or your system lacks ‘eulervm’ LaTeX package then unset the ‘euler’ keyword argument.
To use viewer auto-detection, lets say for ‘png’ output, issue
>>> from sympy import symbols, preview, Symbol
>>> x, y = symbols("x,y")
>>> preview(x + y, output='png')
This will choose ‘pyglet’ by default. To select a different one, do
>>> preview(x + y, output='png', viewer='gimp')
The ‘png’ format is considered special. For all other formats the rules are slightly different. As an example we will take ‘dvi’ output format. If you would run
>>> preview(x + y, output='dvi')
then ‘view’ will look for available ‘dvi’ viewers on your system (predefined in the function, so it will try evince, first, then kdvi and xdvi). If nothing is found you will need to set the viewer explicitly.
>>> preview(x + y, output='dvi', viewer='superior-dvi-viewer')
This will skip auto-detection and will run user specified ‘superior-dvi-viewer’. If ‘view’ fails to find it on your system it will gracefully raise an exception.
You may also enter ‘file’ for the viewer argument. Doing so will cause this function to return a file object in read-only mode, if ‘filename’ is unset. However, if it was set, then ‘preview’ writes the genereted file to this filename instead.
There is also support for writing to a BytesIO like object, which needs to be passed to the ‘outputbuffer’ argument.
>>> from io import BytesIO
>>> obj = BytesIO()
>>> preview(x + y, output='png', viewer='BytesIO',
... outputbuffer=obj)
The LaTeX preamble can be customized by setting the ‘preamble’ keyword argument. This can be used, e.g., to set a different font size, use a custom documentclass or import certain set of LaTeX packages.
>>> preamble = "\\documentclass[10pt]{article}\n" \
... "\\usepackage{amsmath,amsfonts}\\begin{document}"
>>> preview(x + y, output='png', preamble=preamble)
If the value of ‘output’ is different from ‘dvi’ then command line options can be set (‘dvioptions’ argument) for the execution of the ‘dvi’+output conversion tool. These options have to be in the form of a list of strings (see subprocess.Popen).
Additional keyword args will be passed to the latex call, e.g., the symbol_names flag.
>>> phidd = Symbol('phidd')
>>> preview(phidd, symbol_names={phidd:r'\ddot{\varphi}'})
For post-processing the generated TeX File can be written to a file by passing the desired filename to the ‘outputTexFile’ keyword argument. To write the TeX code to a file named “sample.tex” and run the default png viewer to display the resulting bitmap, do
>>> preview(x + y, outputTexFile="sample.tex")
Split a symbol name into a name, superscripts and subscripts
The first part of the symbol name is considered to be its actual ‘name’, followed by super- and subscripts. Each superscript is preceded with a “^” character or by “__”. Each subscript is preceded by a “_” character. The three return values are the actual name, a list with superscripts and a list with subscripts.
>>> from sympy.printing.conventions import split_super_sub
>>> split_super_sub('a_x^1')
('a', ['1'], ['x'])
>>> split_super_sub('var_sub1__sup_sub2')
('var', ['sup'], ['sub1', 'sub2'])
This class is a base class for other classes that implement code-printing functionality, and additionally lists a number of functions that cannot be easily translated to C or Fortran.
The base class for code-printing subclasses.
Raised if an assignment variable for a loop is missing.
Default precedence values for some basic types.
A dictionary assigning precedence values to certain classes. These values are treated like they were inherited, so not every single class has to be named here.
Sometimes it’s not enough to assign a fixed precedence value to a class. Then a function can be inserted in this dictionary that takes an instance of this class as argument and returns the appropriate precedence value.
Returns the precedence of a given object.
unicode character by name or None if not found
Set whether pretty-printer should use unicode by default
See if unicode output is available and leverage it if possible
call str or unicode depending on current mode
The following two functions return the Unicode version of the inputted Greek letter.
list() -> new empty list list(iterable) -> new list initialized from iterable’s items
The following functions return the Unicode subscript/superscript version of the character.
The following functions return Unicode vertical objects.
Construct spatial object of given length.
return: [] of equal-length strings
Construct vertical object of a given height
see: xobj
Construct horizontal object of a given width
see: xobj
The following constants are for rendering roots and fractions.
The following constants/functions are for rendering atoms and symbols.
get symbology for a ‘character’
return pretty representation of an atom
return pretty representation of a symbol
Return a stylised drawing of the letter letter, together with information on how to put annotations (super- and subscripts to the left and to the right) on it.
See pretty.py functions _print_meijerg, _print_hyper on how to use this information.
Prettyprinter by Jurjen Bos. (I hate spammers: mail me at pietjepuk314 at the reverse of ku.oc.oohay). All objects have a method that create a “stringPict”, that can be used in the str method for pretty printing.
An ASCII picture. The pictures are represented as a list of equal length strings.
Put pictures above this picture. Returns string, baseline arguments for stringPict. Baseline is baseline of bottom picture.
Put pictures under this picture. Returns string, baseline arguments for stringPict. Baseline is baseline of top picture
Examples
>>> from sympy.printing.pretty.stringpict import stringPict
>>> print(stringPict("x+3").below(
... stringPict.LINE, '3')[0])
x+3
---
3
The height of the picture in characters.
Put pictures (left to right) at left. Returns string, baseline arguments for stringPict.
Precede object by a slash of the proper size.
Put a string of stringPicts next to each other. Returns string, baseline arguments for stringPict.
Put parentheses around self. Returns string, baseline arguments for stringPict.
left or right can be None or empty string which means ‘no paren from that side’
Return the string form of self.
Unless the argument line_break is set to False, it will break the expression in a form that can be printed on the terminal without being broken up.
Put pictures next to this one. Returns string, baseline arguments for stringPict. (Multiline) strings are allowed, and are given a baseline of 0.
Examples
>>> from sympy.printing.pretty.stringpict import stringPict
>>> print(stringPict("10").right(" + ",stringPict("1\r-\r2",1))[0])
1
10 + -
2
Produce a nice root symbol. Produces ugly results for big n inserts.
Put pictures on top of each other, from top to bottom. Returns string, baseline arguments for stringPict. The baseline is the baseline of the second picture. Everything is centered. Baseline is the baseline of the second picture. Strings are allowed. The special value stringPict.LINE is a row of ‘-‘ extended to the width.
Return the terminal width if possible, otherwise return 0.
The width of the picture in characters.
Extension of the stringPict class that knows about basic math applications, optimizing double minus signs.
“Binding” is interpreted as follows:
ATOM this is an atom: never needs to be parenthesized
FUNC this is a function application: parenthesize if added (?)
DIV this is a division: make wider division if divided
POW this is a power: only parenthesize if exponent
MUL this is a multiplication: parenthesize if powered
ADD this is an addition: parenthesize if multiplied or powered
NEG this is a negative number: optimize if added, parenthesize if
multiplied or powered
OPEN this is an open object: parenthesize if added, multiplied, or
powered (example: Piecewise)
Functions of one or more variables.
DOT description of a SymPy expression tree
Options are
styles: Styles for different classes. The default is:
[(Basic, {'color': 'blue', 'shape': 'ellipse'}),
(Expr, {'color': 'black'})]``
maxdepth: The maximum depth. The default is None, meaning no limit.
Additional keyword arguments are included as styles for the graph.
Examples
>>> from sympy.printing.dot import dotprint
>>> from sympy.abc import x
>>> print(dotprint(x+2))
digraph{
# Graph style
"ordering"="out"
"rankdir"="TD"
#########
# Nodes #
#########
"Add(Integer(2), Symbol(x))_()" ["color"="black", "label"="Add", "shape"="ellipse"];
"Integer(2)_(0,)" ["color"="black", "label"="2", "shape"="ellipse"];
"Symbol(x)_(1,)" ["color"="black", "label"="x", "shape"="ellipse"];
#########
# Edges #
#########
"Add(Integer(2), Symbol(x))_()" -> "Integer(2)_(0,)";
"Add(Integer(2), Symbol(x))_()" -> "Symbol(x)_(1,)";
}