# Module: `core.formatters`

Display formatters.

Inheritance diagram:

## 15 Classes

class `IPython.core.formatters.``DisplayFormatter`(**kwargs)

  Bases: `traitlets.config.configurable.Configurable`

  `format`(obj, include=None, exclude=None)

    Return a format data dict for an object.

    By default all format types will be computed.

    The following MIME types are currently implemented:

    - text/plain
    - text/html
    - text/markdown
    - text/latex
    - application/json
    - application/javascript
    - application/pdf
    - image/png
    - image/jpeg
    - image/svg+xml

    Parameters:

    - obj (object) – The Python object whose format data will be computed.
    - include (list or tuple, optional) – A list of format type strings (MIME types) to include in the format data dict. If this is set only the format types included in this list will be computed.
    - exclude (list or tuple, optional) – A list of format type string (MIME types) to exclude in the format data dict. If this is set all format types will be computed, except for those included in this argument.

    Returns:

    (format_dict, metadata_dict) – format_dict is a dictionary of key/value pairs, one of each format that was generated for the object. The keys are the format types, which will usually be MIME type strings and the values and JSON’able data structure containing the raw data for the representation in that format.

    metadata_dict is a dictionary of metadata about each mime-type output. Its keys will be a strict subset of the keys in format_dict.

    Return type: | tuple of two dicts

  `format_types`

    Return the format types (MIME types) of the active formatters.

class `IPython.core.formatters.``FormatterWarning`

  Bases: `UserWarning`

  Warning class for errors in formatters

class `IPython.core.formatters.``FormatterABC`

  Bases: `abc._NewBase`

  Abstract base class for Formatters.

  A formatter is a callable class that is responsible for computing the raw format data for a particular format type (MIME type). For example, an HTML formatter would have a format type of `text/html` and would return the HTML representation of the object when called.

class `IPython.core.formatters.``BaseFormatter`(**kwargs)

  Bases: `traitlets.config.configurable.Configurable`

  A base formatter class that is configurable.

  This formatter should usually be used as the base class of all formatters. It is a traited `Configurable` class and includes an extensible API for users to determine how their objects are formatted. The following logic is used to find a function to format an given object.

  1. The object is introspected to see if it has a method with the name `print_method`. If is does, that object is passed to that method for formatting.
  2. If no print method is found, three internal dictionaries are consulted to find print method: `singleton_printers`, `type_printers` and `deferred_printers`.

  Users should use these dictionaries to register functions that will be used to compute the format data for their objects (if those objects don’t have the special print methods). The easiest way of using these dictionaries is through the `for_type()` and `for_type_by_name()` methods.

  If no function/callable is found to compute the format data, `None` is returned and this format type is not used.

  `for_type`(typ, func=None)

    Add a format function for a given type.

    Parameters:

    - typ (type or '__module__.__name__' string for a type) – The class of the object that will be formatted using `func`.
    - func (callable) –

      A callable for computing the format data. `func` will be called with the object to be formatted, and will return the raw data in this formatter’s format. Subclasses may use a different call signature for the `func` argument.

      If `func` is None or not specified, there will be no change, only returning the current value.

    Returns: | oldfunc – The currently registered callable. If you are registering a new formatter, this will be the previous value (to enable restoring later).
    Return type: | callable

  `for_type_by_name`(type_module, type_name, func=None)

    Add a format function for a type specified by the full dotted module and name of the type, rather than the type of the object.

    Parameters:

    - type_module (str) – The full dotted name of the module the type is defined in, like `numpy`.
    - type_name (str) – The name of the type (the class name), like `dtype`
    - func (callable) –

      A callable for computing the format data. `func` will be called with the object to be formatted, and will return the raw data in this formatter’s format. Subclasses may use a different call signature for the `func` argument.

      If `func` is None or unspecified, there will be no change, only returning the current value.

    Returns: | oldfunc – The currently registered callable. If you are registering a new formatter, this will be the previous value (to enable restoring later).
    Return type: | callable

  `lookup`(obj)

    Look up the formatter for a given instance.

    Parameters: | obj (object instance) –
    Returns: | f – The registered formatting callable for the type.
    Return type: | callable
    Raises: | KeyError if the type has not been registered.

  `lookup_by_type`(typ)

    Look up the registered formatter for a type.

    Parameters: | typ (type or '__module__.__name__' string for a type) –
    Returns: | f – The registered formatting callable for the type.
    Return type: | callable
    Raises: | KeyError if the type has not been registered.

  `pop`(typ, default=IPython.core.formatters._raise_key_error)

    Pop a formatter for the given type.

    Parameters:

    - typ (type or '__module__.__name__' string for a type) –
    - default (object) – value to be returned if no formatter is registered for typ.

    Returns: | obj – The last registered object for the type.
    Return type: | object
    Raises: | KeyError if the type is not registered and default is not specified.

class `IPython.core.formatters.``PlainTextFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  The default pretty-printer.

  This uses `IPython.lib.pretty` to compute the format data of the object. If the object cannot be pretty printed, `repr()` is used. See the documentation of `IPython.lib.pretty` for details on how to write pretty printers. Here is a simple example:

      def dtype_pprinter(obj, p, cycle):
          if cycle:
              return p.text('dtype(...)')
          if hasattr(obj, 'fields'):
              if obj.fields is None:
                  p.text(repr(obj))
              else:
                  p.begin_group(7, 'dtype([')
                  for i, field in enumerate(obj.descr):
                      if i > 0:
                          p.text(',')
                          p.breakable()
                      p.pretty(field)
                  p.end_group(7, '])')

class `IPython.core.formatters.``HTMLFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  An HTML formatter.

  To define the callables that compute the HTML representation of your objects, define a `_repr_html_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be a valid HTML snippet that could be injected into an existing DOM. It should not include the ``<html>` or ``<body>` tags.

class `IPython.core.formatters.``MarkdownFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A Markdown formatter.

  To define the callables that compute the Markdown representation of your objects, define a `_repr_markdown_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be a valid Markdown.

class `IPython.core.formatters.``SVGFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  An SVG formatter.

  To define the callables that compute the SVG representation of your objects, define a `_repr_svg_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be valid SVG enclosed in ``<svg>`` tags, that could be injected into an existing DOM. It should not include the ``<html>` or ``<body>` tags.

class `IPython.core.formatters.``PNGFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A PNG formatter.

  To define the callables that compute the PNG representation of your objects, define a `_repr_png_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be raw PNG data, not base64 encoded.

class `IPython.core.formatters.``JPEGFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A JPEG formatter.

  To define the callables that compute the JPEG representation of your objects, define a `_repr_jpeg_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be raw JPEG data, not base64 encoded.

class `IPython.core.formatters.``LatexFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A LaTeX formatter.

  To define the callables that compute the LaTeX representation of your objects, define a `_repr_latex_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be a valid LaTeX equation, enclosed in either ``$``, ``$$`` or another LaTeX equation environment.

class `IPython.core.formatters.``JSONFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A JSON string formatter.

  To define the callables that compute the JSONable representation of your objects, define a `_repr_json_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be a JSONable list or dict. JSON scalars (None, number, string) are not allowed, only dict or list containers.

class `IPython.core.formatters.``JavascriptFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A Javascript formatter.

  To define the callables that compute the Javascript representation of your objects, define a `_repr_javascript_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be valid Javascript code and should not be enclosed in ``<script>`` tags.

class `IPython.core.formatters.``PDFFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A PDF formatter.

  To define the callables that compute the PDF representation of your objects, define a `_repr_pdf_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this.

  The return value of this formatter should be raw PDF data, not base64 encoded.

class `IPython.core.formatters.``IPythonDisplayFormatter`(**kwargs)

  Bases: `IPython.core.formatters.BaseFormatter`

  A Formatter for objects that know how to display themselves.

  To define the callables that compute the representation of your objects, define a `_ipython_display_()` method or use the `for_type()` or `for_type_by_name()` methods to register functions that handle this. Unlike mime-type displays, this method should not return anything, instead calling any appropriate display methods itself.

  This display formatter has highest priority. If it fires, no other display formatter will be called.

## 2 Functions

`IPython.core.formatters.``catch_format_error`(method, self, *args, **kwargs)

  show traceback on failed format call

`IPython.core.formatters.``format_display_data`(obj, include=None, exclude=None)

  Return a format data dict for an object.

  By default all format types will be computed.

  The following MIME types are currently implemented:

  - text/plain
  - text/html
  - text/markdown
  - text/latex
  - application/json
  - application/javascript
  - application/pdf
  - image/png
  - image/jpeg
  - image/svg+xml

  Parameters: | obj (object) – The Python object whose format data will be computed.

  Returns:

  - format_dict (dict) – A dictionary of key/value pairs, one or each format that was generated for the object. The keys are the format types, which will usually be MIME type strings and the values and JSON’able data structure containing the raw data for the representation in that format.
  - include (list or tuple, optional) – A list of format type strings (MIME types) to include in the format data dict. If this is set only the format types included in this list will be computed.
  - exclude (list or tuple, optional) – A list of format type string (MIME types) to exclue in the format data dict. If this is set all format types will be computed, except for those included in this argument.