qnet.printing.base module

Provides the base class for Printers

Summary

Classes:

QnetBasePrinter Base class for all QNET expression printers

Reference

class qnet.printing.base.QnetBasePrinter(cache=None, settings=None)[source]

Bases: sympy.printing.printer.Printer

Base class for all QNET expression printers

Parameters:
  • cache (dict or None) – A dict that maps expressions to strings. It may be given during istantiation to use pre-defined strings for specific expressions. The cache will be updated as the printer is used.
  • settings (dict or None) – A dict of settings.
Class Attributes:
 
  • sympy_printer_cls (type) – The class that will be instantiated to print Sympy expressions
  • _default_settings (dict) – The default value of all settings. Note only settings for which there are defaults defined here are accepted when instantiating the printer
  • printmethod (None or str) – Name of a method that expressions may define to print themeselves.
Attributes:
  • cache (dict) – Dictionary where the results of any call to doprint() is stored. When doprint() is called for an expression that is already in cache, the result from the cache is returned.
  • _sympy_printer (sympy.printing.printer.Printer) – The printer instance that will be used to print any Sympy expression.
  • _allow_caching (bool) – A flag that may be set to completely disable caching
  • _print_level (int) – The recursion depth of doprint() (>= 1 inside any of the _print* methods)
Raises:

TypeError – If any key in settings is not defined in the _default_settings of the printer, respectively the sympy_printer_cls.
sympy_printer_cls

alias of qnet.printing.sympy.SympyStrPrinter

printmethod = None
emptyPrinter(expr)[source]

Fallback method for expressions that neither know how to print themeselves, nor for which the printer has a suitable _print* method

doprint(expr, *args, **kwargs)[source]

Returns printer’s representation for expr (as a string)

The representation is obtained by the following methods:

  1. from the cache
  2. If expr is a Sympy object, delegate to the doprint() method of _sympy_printer
  3. Let the expr print itself if has the printmethod
  4. Take the best fitting _print_* method of the printer
  5. As fallback, delegate to emptyPrinter()

Any extra args or kwargs are passed to the internal _print method.