Source code for astropy.table.pprint
# Licensed under a 3-clause BSD style license - see LICENSE.rst
import fnmatch
import os
import re
import sys
from shutil import get_terminal_size
import numpy as np
from astropy import log
from astropy.utils.console import Getch, color_print, conf
from astropy.utils.data_info import dtype_info_name
__all__ = []
def default_format_func(format_, val):
if isinstance(val, bytes):
return val.decode("utf-8", errors="replace")
else:
return str(val)
# The first three functions are helpers for _auto_format_func
def _use_str_for_masked_values(format_func):
"""Wrap format function to trap masked values.
String format functions and most user functions will not be able to deal
with masked values, so we wrap them to ensure they are passed to str().
"""
return lambda format_, val: (
str(val) if val is np.ma.masked else format_func(format_, val)
)
def _possible_string_format_functions(format_):
"""Iterate through possible string-derived format functions.
A string can either be a format specifier for the format built-in,
a new-style format string, or an old-style format string.
"""
yield lambda format_, val: format(val, format_)
yield lambda format_, val: format_.format(val)
yield lambda format_, val: format_ % val
yield lambda format_, val: format_.format(**{k: val[k] for k in val.dtype.names})
def get_auto_format_func(
col=None, possible_string_format_functions=_possible_string_format_functions
):
"""
Return a wrapped ``auto_format_func`` function which is used in
formatting table columns. This is primarily an internal function but
gets used directly in other parts of astropy, e.g. `astropy.io.ascii`.
Parameters
----------
col_name : object, optional
Hashable object to identify column like id or name. Default is None.
possible_string_format_functions : func, optional
Function that yields possible string formatting functions
(defaults to internal function to do this).
Returns
-------
Wrapped ``auto_format_func`` function
"""
def _auto_format_func(format_, val):
"""Format ``val`` according to ``format_`` for a plain format specifier,
old- or new-style format strings, or using a user supplied function.
More importantly, determine and cache (in _format_funcs) a function
that will do this subsequently. In this way this complicated logic is
only done for the first value.
Returns the formatted value.
"""
if format_ is None:
return default_format_func(format_, val)
if format_ in col.info._format_funcs:
return col.info._format_funcs[format_](format_, val)
if callable(format_):
format_func = lambda format_, val: format_(val)
try:
out = format_func(format_, val)
if not isinstance(out, str):
raise ValueError(
f"Format function for value {val} returned {type(val)} "
"instead of string type"
)
except Exception as err:
# For a masked element, the format function call likely failed
# to handle it. Just return the string representation for now,
# and retry when a non-masked value comes along.
if val is np.ma.masked:
return str(val)
raise ValueError(f"Format function for value {val} failed.") from err
# If the user-supplied function handles formatting masked elements, use
# it directly. Otherwise, wrap it in a function that traps them.
try:
format_func(format_, np.ma.masked)
except Exception:
format_func = _use_str_for_masked_values(format_func)
else:
# For a masked element, we cannot set string-based format functions yet,
# as all tests below will fail. Just return the string representation
# of masked for now, and retry when a non-masked value comes along.
if val is np.ma.masked:
return str(val)
for format_func in possible_string_format_functions(format_):
try:
# Does this string format method work?
out = format_func(format_, val)
# Require that the format statement actually did something.
if out == format_:
raise ValueError("the format passed in did nothing.")
except Exception:
continue
else:
break
else:
# None of the possible string functions passed muster.
raise ValueError(
f"unable to parse format string {format_} for its column."
)
# String-based format functions will fail on masked elements;
# wrap them in a function that traps them.
format_func = _use_str_for_masked_values(format_func)
col.info._format_funcs[format_] = format_func
return out
return _auto_format_func
def _get_pprint_include_names(table):
"""Get the set of names to show in pprint from the table pprint_include_names
and pprint_exclude_names attributes.
These may be fnmatch unix-style globs.
"""
def get_matches(name_globs, default):
match_names = set()
if name_globs: # For None or () use the default
for name in table.colnames:
for name_glob in name_globs:
if fnmatch.fnmatch(name, name_glob):
match_names.add(name)
break
else:
match_names.update(default)
return match_names
include_names = get_matches(table.pprint_include_names(), table.colnames)
exclude_names = get_matches(table.pprint_exclude_names(), [])
return include_names - exclude_names
[docs]
class TableFormatter:
@staticmethod
def _get_pprint_size(max_lines=None, max_width=None):
"""Get the output size (number of lines and character width) for Column and
Table pformat/pprint methods.
If no value of ``max_lines`` is supplied then the height of the
screen terminal is used to set ``max_lines``. If the terminal
height cannot be determined then the default will be determined
using the ``astropy.table.conf.max_lines`` configuration item. If a
negative value of ``max_lines`` is supplied then there is no line
limit applied.
The same applies for max_width except the configuration item is
``astropy.table.conf.max_width``.
Parameters
----------
max_lines : int or None
Maximum lines of output (header + data rows)
max_width : int or None
Maximum width (characters) output
Returns
-------
max_lines, max_width : int
"""
# Declare to keep static type checker happy.
lines = None
width = None
if max_lines is None:
max_lines = conf.max_lines
if max_width is None:
max_width = conf.max_width
if max_lines is None or max_width is None:
width, lines = get_terminal_size()
if max_lines is None:
max_lines = lines
elif max_lines < 0:
max_lines = sys.maxsize
if max_lines < 8:
max_lines = 8
if max_width is None:
max_width = width
elif max_width < 0:
max_width = sys.maxsize
if max_width < 10:
max_width = 10
return max_lines, max_width
def _pformat_col(
self,
col,
max_lines=None,
show_name=True,
show_unit=None,
show_dtype=False,
show_length=None,
html=False,
align=None,
):
"""Return a list of formatted string representation of column values.
Parameters
----------
max_lines : int
Maximum lines of output (header + data rows)
show_name : bool
Include column name. Default is True.
show_unit : bool
Include a header row for unit. Default is to show a row
for units only if one or more columns has a defined value
for the unit.
show_dtype : bool
Include column dtype. Default is False.
show_length : bool
Include column length at end. Default is to show this only
if the column is not shown completely.
html : bool
Output column as HTML
align : str
Left/right alignment of columns. Default is '>' (right) for all
columns. Other allowed values are '<', '^', and '0=' for left,
centered, and 0-padded, respectively.
Returns
-------
lines : list
List of lines with formatted column values
outs : dict
Dict which is used to pass back additional values
defined within the iterator.
"""
if show_unit is None:
show_unit = col.info.unit is not None
outs = {} # Some values from _pformat_col_iter iterator that are needed here
col_strs_iter = self._pformat_col_iter(
col,
max_lines,
show_name=show_name,
show_unit=show_unit,
show_dtype=show_dtype,
show_length=show_length,
outs=outs,
)
# Replace tab and newline with text representations so they display nicely.
# Newline in particular is a problem in a multicolumn table.
col_strs = [
val.replace("\t", "\\t").replace("\n", "\\n") for val in col_strs_iter
]
if len(col_strs) > 0:
col_width = max(len(x) for x in col_strs)
if html:
from astropy.utils.xml.writer import xml_escape
n_header = outs["n_header"]
for i, col_str in enumerate(col_strs):
# _pformat_col output has a header line '----' which is not needed here
if i == n_header - 1:
continue
td = "th" if i < n_header else "td"
val = f"<{td}>{xml_escape(col_str.strip())}</{td}>"
row = "<tr>" + val + "</tr>"
if i < n_header:
row = "<thead>" + row + "</thead>"
col_strs[i] = row
if n_header > 0:
# Get rid of '---' header line
col_strs.pop(n_header - 1)
col_strs.insert(0, "<table>")
col_strs.append("</table>")
# Now bring all the column string values to the same fixed width
else:
col_width = max(len(x) for x in col_strs) if col_strs else 1
# Center line header content and generate dashed headerline
for i in outs["i_centers"]:
col_strs[i] = col_strs[i].center(col_width)
if outs["i_dashes"] is not None:
col_strs[outs["i_dashes"]] = "-" * col_width
# Format columns according to alignment. `align` arg has precedent, otherwise
# use `col.format` if it starts as a legal alignment string. If neither applies
# then right justify.
re_fill_align = re.compile(r"(?P<fill>.?)(?P<align>[<^>=])")
match = None
if align:
# If there is an align specified then it must match
match = re_fill_align.match(align)
if not match:
raise ValueError(
"column align must be one of '<', '^', '>', or '='"
)
elif isinstance(col.info.format, str):
# col.info.format need not match, in which case rjust gets used
match = re_fill_align.match(col.info.format)
if match:
fill_char = match.group("fill")
align_char = match.group("align")
if align_char == "=":
if fill_char != "0":
raise ValueError("fill character must be '0' for '=' align")
# str.zfill gets used which does not take fill char arg
fill_char = ""
else:
fill_char = ""
align_char = ">"
justify_methods = {"<": "ljust", "^": "center", ">": "rjust", "=": "zfill"}
justify_method = justify_methods[align_char]
justify_args = (col_width, fill_char) if fill_char else (col_width,)
for i, col_str in enumerate(col_strs):
col_strs[i] = getattr(col_str, justify_method)(*justify_args)
if outs["show_length"]:
col_strs.append(f"Length = {len(col)} rows")
return col_strs, outs
def _name_and_structure(self, name, dtype, sep=" "):
"""Format a column name, including a possible structure.
Normally, just returns the name, but if it has a structured dtype,
will add the parts in between square brackets. E.g.,
"name [f0, f1]" or "name [f0[sf0, sf1], f1]".
"""
if dtype is None or dtype.names is None:
return name
structure = ", ".join(
[
self._name_and_structure(name, dt, sep="")
for name, (dt, _) in dtype.fields.items()
]
)
return f"{name}{sep}[{structure}]"
def _pformat_col_iter(
self,
col,
max_lines,
show_name,
show_unit,
outs,
show_dtype=False,
show_length=None,
):
"""Iterator which yields formatted string representation of column values.
Parameters
----------
max_lines : int
Maximum lines of output (header + data rows)
show_name : bool
Include column name. Default is True.
show_unit : bool
Include a header row for unit. Default is to show a row
for units only if one or more columns has a defined value
for the unit.
outs : dict
Must be a dict which is used to pass back additional values
defined within the iterator.
show_dtype : bool
Include column dtype. Default is False.
show_length : bool
Include column length at end. Default is to show this only
if the column is not shown completely.
"""
max_lines, _ = self._get_pprint_size(max_lines, -1)
dtype = getattr(col, "dtype", None)
multidims = getattr(col, "shape", [0])[1:]
if multidims:
multidim0 = tuple(0 for n in multidims)
multidim1 = tuple(n - 1 for n in multidims)
multidims_all_ones = np.prod(multidims) == 1
multidims_has_zero = 0 in multidims
i_dashes = None
i_centers = [] # Line indexes where content should be centered
n_header = 0
if show_name:
i_centers.append(n_header)
# Get column name (or 'None' if not set)
col_name = str(col.info.name)
n_header += 1
yield self._name_and_structure(col_name, dtype)
if show_unit:
i_centers.append(n_header)
n_header += 1
yield str(col.info.unit or "")
if show_dtype:
i_centers.append(n_header)
n_header += 1
if dtype is not None:
# For zero-length strings, np.dtype((dtype, ())) does not work;
# see https://github.com/numpy/numpy/issues/27301
# As a work-around, just omit the shape if there is none.
col_dtype = dtype_info_name((dtype, multidims) if multidims else dtype)
else:
col_dtype = col.__class__.__qualname__ or "object"
yield col_dtype
if show_unit or show_name or show_dtype:
i_dashes = n_header
n_header += 1
yield "---"
max_lines -= n_header
n_print2 = max_lines // 2
try:
n_rows = len(col)
except TypeError:
is_scalar = True
n_rows = 1
else:
is_scalar = False
# This block of code is responsible for producing the function that
# will format values for this column. The ``format_func`` function
# takes two args (col_format, val) and returns the string-formatted
# version. Some points to understand:
#
# - col_format could itself be the formatting function, so it will
# actually end up being called with itself as the first arg. In
# this case the function is expected to ignore its first arg.
#
# - auto_format_func is a function that gets called on the first
# column value that is being formatted. It then determines an
# appropriate formatting function given the actual value to be
# formatted. This might be deterministic or it might involve
# try/except. The latter allows for different string formatting
# options like %f or {:5.3f}. When auto_format_func is called it:
# 1. Caches the function in the _format_funcs dict so for subsequent
# values the right function is called right away.
# 2. Returns the formatted value.
#
# - possible_string_format_functions is a function that yields a
# succession of functions that might successfully format the
# value. There is a default, but Mixin methods can override this.
# See Quantity for an example.
#
# - get_auto_format_func() returns a wrapped version of auto_format_func
# with the column id and possible_string_format_functions as
# enclosed variables.
col_format = col.info.format or getattr(col.info, "default_format", None)
pssf = (
getattr(col.info, "possible_string_format_functions", None)
or _possible_string_format_functions
)
auto_format_func = get_auto_format_func(col, pssf)
format_func = col.info._format_funcs.get(col_format, auto_format_func)
if n_rows > max_lines:
if show_length is None:
show_length = True
i0 = n_print2 - (1 if show_length else 0)
i1 = n_rows - n_print2 - max_lines % 2
indices = np.concatenate([np.arange(0, i0 + 1), np.arange(i1 + 1, n_rows)])
else:
i0 = -1
indices = np.arange(n_rows)
def format_col_str(idx):
if multidims:
# Prevents columns like Column(data=[[(1,)],[(2,)]], name='a')
# with shape (n,1,...,1) from being printed as if there was
# more than one element in a row
if multidims_all_ones:
return format_func(col_format, col[(idx,) + multidim0])
elif multidims_has_zero:
# Any zero dimension means there is no data to print
return ""
else:
left = format_func(col_format, col[(idx,) + multidim0])
right = format_func(col_format, col[(idx,) + multidim1])
return f"{left} .. {right}"
elif is_scalar:
return format_func(col_format, col)
else:
return format_func(col_format, col[idx])
# Add formatted values if within bounds allowed by max_lines
for idx in indices:
if idx == i0:
yield "..."
else:
try:
yield format_col_str(idx)
except ValueError:
raise ValueError(
f'Unable to parse format string "{col_format}" for '
f'entry "{col[idx]}" in column "{col.info.name}"'
)
outs["show_length"] = show_length
outs["n_header"] = n_header
outs["i_centers"] = i_centers
outs["i_dashes"] = i_dashes
def _pformat_table(
self,
table,
max_lines=-1,
max_width=-1,
show_name=True,
show_unit=None,
show_dtype=False,
html=False,
tableid=None,
tableclass=None,
align=None,
):
"""Return a list of lines for the formatted string representation of
the table.
Parameters
----------
max_lines : int or None
Maximum number of rows to output
-1 (default) implies no limit, ``None`` implies using the
height of the current terminal.
max_width : int or None
Maximum character width of output
-1 (default) implies no limit, ``None`` implies using the
width of the current terminal.
show_name : bool
Include a header row for column names. Default is True.
show_unit : bool
Include a header row for unit. Default is to show a row
for units only if one or more columns has a defined value
for the unit.
show_dtype : bool
Include a header row for column dtypes. Default is to False.
html : bool
Format the output as an HTML table. Default is False.
tableid : str or None
An ID tag for the table; only used if html is set. Default is
"table{id}", where id is the unique integer id of the table object,
id(table)
tableclass : str or list of str or None
CSS classes for the table; only used if html is set. Default is
none
align : str or list or tuple
Left/right alignment of columns. Default is '>' (right) for all
columns. Other allowed values are '<', '^', and '0=' for left,
centered, and 0-padded, respectively. A list of strings can be
provided for alignment of tables with multiple columns.
Returns
-------
rows : list
Formatted table as a list of strings
outs : dict
Dict which is used to pass back additional values
defined within the iterator.
"""
# "Print" all the values into temporary lists by column for subsequent
# use and to determine the width
max_lines, max_width = self._get_pprint_size(max_lines, max_width)
if show_unit is None:
show_unit = any(col.info.unit for col in table.columns.values())
# Coerce align into a correctly-sized list of alignments (if possible)
n_cols = len(table.columns)
if align is None or isinstance(align, str):
align = [align] * n_cols
elif isinstance(align, (list, tuple)):
if len(align) != n_cols:
raise ValueError(
f"got {len(align)} alignment values instead of "
f"the number of columns ({n_cols})"
)
else:
raise TypeError(
f"align keyword must be str or list or tuple (got {type(align)})"
)
# Process column visibility from table pprint_include_names and
# pprint_exclude_names attributes and get the set of columns to show.
pprint_include_names = _get_pprint_include_names(table)
cols = []
outs = None # Initialize so static type checker is happy
for align_, col in zip(align, table.columns.values()):
if col.info.name not in pprint_include_names:
continue
lines, outs = self._pformat_col(
col,
max_lines,
show_name=show_name,
show_unit=show_unit,
show_dtype=show_dtype,
align=align_,
)
if outs["show_length"]:
lines = lines[:-1]
cols.append(lines)
if not cols:
return ["<No columns>"], {"show_length": False}
# Use the values for the last column since they are all the same
n_header = outs["n_header"]
n_rows = len(cols[0])
def outwidth(cols):
return sum(len(c[0]) for c in cols) + len(cols) - 1
dots_col = ["..."] * n_rows
middle = len(cols) // 2
while outwidth(cols) > max_width:
if len(cols) == 1:
break
if len(cols) == 2:
cols[1] = dots_col
break
if cols[middle] is dots_col:
cols.pop(middle)
middle = len(cols) // 2
cols[middle] = dots_col
# Now "print" the (already-stringified) column values into a
# row-oriented list.
rows = []
if html:
from astropy.utils.xml.writer import xml_escape
if tableid is None:
tableid = f"table{id(table)}"
if tableclass is not None:
if isinstance(tableclass, list):
tableclass = " ".join(tableclass)
rows.append(f'<table id="{tableid}" class="{tableclass}">')
else:
rows.append(f'<table id="{tableid}">')
for i in range(n_rows):
# _pformat_col output has a header line '----' which is not needed here
if i == n_header - 1:
continue
td = "th" if i < n_header else "td"
vals = (f"<{td}>{xml_escape(col[i].strip())}</{td}>" for col in cols)
row = "<tr>" + "".join(vals) + "</tr>"
if i < n_header:
row = "<thead>" + row + "</thead>"
rows.append(row)
rows.append("</table>")
else:
for i in range(n_rows):
row = " ".join(col[i] for col in cols)
rows.append(row)
return rows, outs
def _more_tabcol(
self,
tabcol,
max_lines=None,
max_width=None,
show_name=True,
show_unit=None,
show_dtype=False,
):
"""Interactive "more" of a table or column.
Parameters
----------
max_lines : int or None
Maximum number of rows to output
max_width : int or None
Maximum character width of output
show_name : bool
Include a header row for column names. Default is True.
show_unit : bool
Include a header row for unit. Default is to show a row
for units only if one or more columns has a defined value
for the unit.
show_dtype : bool
Include a header row for column dtypes. Default is False.
"""
allowed_keys = "f br<>qhpn"
# Count the header lines
n_header = 0
if show_name:
n_header += 1
if show_unit:
n_header += 1
if show_dtype:
n_header += 1
if show_name or show_unit or show_dtype:
n_header += 1
# Set up kwargs for pformat call. Only Table gets max_width.
kwargs = dict(
max_lines=-1,
show_name=show_name,
show_unit=show_unit,
show_dtype=show_dtype,
)
if hasattr(tabcol, "columns"): # tabcol is a table
kwargs["max_width"] = max_width
# If max_lines is None (=> query screen size) then increase by 2.
# This is because get_pprint_size leaves 6 extra lines so that in
# ipython you normally see the last input line.
max_lines1, max_width = self._get_pprint_size(max_lines, max_width)
if max_lines is None:
max_lines1 += 2
delta_lines = max_lines1 - n_header
# Set up a function to get a single character on any platform
inkey = Getch()
i0 = 0 # First table/column row to show
showlines = True
while True:
i1 = i0 + delta_lines # Last table/col row to show
if showlines: # Don't always show the table (e.g. after help)
try:
os.system("cls" if os.name == "nt" else "clear")
except Exception:
pass # No worries if clear screen call fails
lines = tabcol[i0:i1].pformat(**kwargs)
colors = (
"red" if i < n_header else "default" for i in range(len(lines))
)
for color, line in zip(colors, lines):
color_print(line, color)
showlines = True
print()
print("-- f, <space>, b, r, p, n, <, >, q h (help) --", end=" ")
# Get a valid key
while True:
try:
key = inkey().lower()
except Exception:
print("\n")
log.error(
"Console does not support getting a character"
" as required by more(). Use pprint() instead."
)
return
if key in allowed_keys:
break
print(key)
if key.lower() == "q":
break
if key == " " or key == "f":
i0 += delta_lines
elif key == "b":
i0 = i0 - delta_lines
elif key == "r":
pass
elif key == "<":
i0 = 0
elif key == ">":
i0 = len(tabcol)
elif key == "p":
i0 -= 1
elif key == "n":
i0 += 1
elif key == "h":
showlines = False
print(
"""
Browsing keys:
f, <space> : forward one page
b : back one page
r : refresh same page
n : next row
p : previous row
< : go to beginning
> : go to end
q : quit browsing
h : print this help""",
end=" ",
)
if i0 < 0:
i0 = 0
if i0 >= len(tabcol) - delta_lines:
i0 = len(tabcol) - delta_lines
print("\n")