REF: simplify Categorical.__repr__ (#55391)

* REF: remove unused arguments from private Categorical methods * REF: remove unused args from CategoricalFormatter * REF: remove CategoricalFormatter

Author: jbrockmendel

pandas/core/arrays/categorical.py

@@ -2151,21 +2151,6 @@ def _formatter(self, boxed: bool = False):
  # Defer to CategoricalFormatter's formatter.
  return None
 
- def _tidy_repr(self, max_vals: int = 10, footer: bool = True) -> str:
- """
- a short repr displaying only max_vals and an optional (but default
- footer)
- """
- num = max_vals // 2
- head = self[:num]._get_repr(length=False, footer=False)
- tail = self[-(max_vals - num) :]._get_repr(length=False, footer=False)
-
- result = f"{head[:-1]}, ..., {tail[1:]}"
- if footer:
- result = f"{result}\n{self._repr_footer()}"
-
- return str(result)
-
  def _repr_categories(self) -> list[str]:
  """
  return the base repr for the categories
@@ -2221,33 +2206,49 @@ def _repr_categories_info(self) -> str:
  # replace to simple save space by
  return f"{levheader}[{levstring.replace(' < ... < ', ' ... ')}]"
 
- def _repr_footer(self) -> str:
- info = self._repr_categories_info()
- return f"Length: {len(self)}\n{info}"
-
- def _get_repr(
- self, length: bool = True, na_rep: str = "NaN", footer: bool = True
- ) -> str:
+ def _get_values_repr(self) -> str:
  from pandas.io.formats import format as fmt
 
- formatter = fmt.CategoricalFormatter(
- self, length=length, na_rep=na_rep, footer=footer
+ assert len(self) > 0
+
+ vals = self._internal_get_values()
+ fmt_values = fmt.format_array(
+ vals,
+ None,
+ float_format=None,
+ na_rep="NaN",
+ quoting=QUOTE_NONNUMERIC,
  )
- result = formatter.to_string()
- return str(result)
+
+ fmt_values = [i.strip() for i in fmt_values]
+ joined = ", ".join(fmt_values)
+ result = "[" + joined + "]"
+ return result
 
  def __repr__(self) -> str:
  """
  String representation.
  """
- _maxlen = 10
- if len(self._codes) > _maxlen:
- result = self._tidy_repr(_maxlen)
- elif len(self._codes) > 0:
- result = self._get_repr(length=len(self) > _maxlen)
+ footer = self._repr_categories_info()
+ length = len(self)
+ max_len = 10
+ if length > max_len:
+ # In long cases we do not display all entries, so we add Length
+ # information to the __repr__.
+ num = max_len // 2
+ head = self[:num]._get_values_repr()
+ tail = self[-(max_len - num) :]._get_values_repr()
+ body = f"{head[:-1]}, ..., {tail[1:]}"
+ length_info = f"Length: {len(self)}"
+ result = f"{body}\n{length_info}\n{footer}"
+ elif length > 0:
+ body = self._get_values_repr()
+ result = f"{body}\n{footer}"
  else:
- msg = self._get_repr(length=False, footer=True).replace("\n", ", ")
- result = f"[], {msg}"
+ # In the empty case we use a comma instead of newline to get
+ # a more compact __repr__
+ body = "[]"
+ result = f"{body}, {footer}"
 
  return result
 

pandas/io/formats/format.py

@@ -12,10 +12,7 @@
  Sequence,
 )
 from contextlib import contextmanager
-from csv import (
- QUOTE_NONE,
- QUOTE_NONNUMERIC,
-)
+from csv import QUOTE_NONE
 from decimal import Decimal
 from functools import partial
 from io import StringIO
@@ -200,70 +197,6 @@
  """
 
 
-class CategoricalFormatter:
- def __init__(
- self,
- categorical: Categorical,
- buf: IO[str] | None = None,
- length: bool = True,
- na_rep: str = "NaN",
- footer: bool = True,
- ) -> None:
- self.categorical = categorical
- self.buf = buf if buf is not None else StringIO("")
- self.na_rep = na_rep
- self.length = length
- self.footer = footer
- self.quoting = QUOTE_NONNUMERIC
-
- def _get_footer(self) -> str:
- footer = ""
-
- if self.length:
- if footer:
- footer += ", "
- footer += f"Length: {len(self.categorical)}"
-
- level_info = self.categorical._repr_categories_info()
-
- # Levels are added in a newline
- if footer:
- footer += "\n"
- footer += level_info
-
- return str(footer)
-
- def _get_formatted_values(self) -> list[str]:
- return format_array(
- self.categorical._internal_get_values(),
- None,
- float_format=None,
- na_rep=self.na_rep,
- quoting=self.quoting,
- )
-
- def to_string(self) -> str:
- categorical = self.categorical
-
- if len(categorical) == 0:
- if self.footer:
- return self._get_footer()
- else:
- return ""
-
- fmt_values = self._get_formatted_values()
-
- fmt_values = [i.strip() for i in fmt_values]
- values = ", ".join(fmt_values)
- result = ["[" + values + "]"]
- if self.footer:
- footer = self._get_footer()
- if footer:
- result.append(footer)
-
- return str("\n".join(result))
-
-
 class SeriesFormatter:
  def __init__(
  self,