"""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.
Updates by Jason Gedge (email <my last name> at cs mun ca)
- terminal_string() method
- minor fixes and changes (mostly to prettyForm)
TODO:
- Allow left/center/right alignment options for above/below and
top/center/bottom alignment options for left/right
"""
from __future__ import print_function, division
from .pretty_symbology import hobj, vobj, xsym, xobj, pretty_use_unicode
from sympy.core.compatibility import string_types, range, unicode
[docs]class stringPict(object):
"""An ASCII picture.
The pictures are represented as a list of equal length strings.
"""
#special value for stringPict.below
LINE = 'line'
def __init__(self, s, baseline=0):
"""Initialize from string.
Multiline strings are centered.
"""
self.s = s
#picture is a string that just can be printed
self.picture = stringPict.equalLengths(s.splitlines())
#baseline is the line number of the "base line"
self.baseline = baseline
self.binding = None
@staticmethod
def equalLengths(lines):
# empty lines
if not lines:
return ['']
width = max(len(line) for line in lines)
return [line.center(width) for line in lines]
[docs] def height(self):
"""The height of the picture in characters."""
return len(self.picture)
[docs] def width(self):
"""The width of the picture in characters."""
return len(self.picture[0])
[docs] @staticmethod
def next(*args):
"""Put a string of stringPicts next to each other.
Returns string, baseline arguments for stringPict.
"""
#convert everything to stringPicts
objects = []
for arg in args:
if isinstance(arg, string_types):
arg = stringPict(arg)
objects.append(arg)
#make a list of pictures, with equal height and baseline
newBaseline = max(obj.baseline for obj in objects)
newHeightBelowBaseline = max(
obj.height() - obj.baseline
for obj in objects)
newHeight = newBaseline + newHeightBelowBaseline
pictures = []
for obj in objects:
oneEmptyLine = [' '*obj.width()]
basePadding = newBaseline - obj.baseline
totalPadding = newHeight - obj.height()
pictures.append(
oneEmptyLine * basePadding +
obj.picture +
oneEmptyLine * (totalPadding - basePadding))
result = [''.join(lines) for lines in zip(*pictures)]
return '\n'.join(result), newBaseline
[docs] def right(self, *args):
r"""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
"""
return stringPict.next(self, *args)
[docs] def left(self, *args):
"""Put pictures (left to right) at left.
Returns string, baseline arguments for stringPict.
"""
return stringPict.next(*(args + (self,)))
[docs] @staticmethod
def stack(*args):
"""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.
"""
#convert everything to stringPicts; keep LINE
objects = []
for arg in args:
if arg is not stringPict.LINE and isinstance(arg, string_types):
arg = stringPict(arg)
objects.append(arg)
#compute new width
newWidth = max(
obj.width()
for obj in objects
if obj is not stringPict.LINE)
lineObj = stringPict(hobj('-', newWidth))
#replace LINE with proper lines
for i, obj in enumerate(objects):
if obj is stringPict.LINE:
objects[i] = lineObj
#stack the pictures, and center the result
newPicture = []
for obj in objects:
newPicture.extend(obj.picture)
newPicture = [line.center(newWidth) for line in newPicture]
newBaseline = objects[0].height() + objects[1].baseline
return '\n'.join(newPicture), newBaseline
[docs] def below(self, *args):
"""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]) #doctest: +NORMALIZE_WHITESPACE
x+3
---
3
"""
s, baseline = stringPict.stack(self, *args)
return s, self.baseline
[docs] def above(self, *args):
"""Put pictures above this picture.
Returns string, baseline arguments for stringPict.
Baseline is baseline of bottom picture.
"""
string, baseline = stringPict.stack(*(args + (self,)))
baseline = len(string.splitlines()) - self.height() + self.baseline
return string, baseline
[docs] def parens(self, left='(', right=')', ifascii_nougly=False):
"""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'
"""
h = self.height()
b = self.baseline
# XXX this is a hack -- ascii parens are ugly!
if ifascii_nougly and not pretty_use_unicode():
h = 1
b = 0
res = self
if left:
lparen = stringPict(vobj(left, h), baseline=b)
res = stringPict(*lparen.right(self))
if right:
rparen = stringPict(vobj(right, h), baseline=b)
res = stringPict(*res.right(rparen))
return ('\n'.join(res.picture), res.baseline)
[docs] def leftslash(self):
"""Precede object by a slash of the proper size.
"""
# XXX not used anywhere ?
height = max(
self.baseline,
self.height() - 1 - self.baseline)*2 + 1
slash = '\n'.join(
' '*(height - i - 1) + xobj('/', 1) + ' '*i
for i in range(height)
)
return self.left(stringPict(slash, height//2))
[docs] def root(self, n=None):
"""Produce a nice root symbol.
Produces ugly results for big n inserts.
"""
# XXX not used anywhere
# XXX duplicate of root drawing in pretty.py
#put line over expression
result = self.above('_'*self.width())
#construct right half of root symbol
height = self.height()
slash = '\n'.join(
' ' * (height - i - 1) + '/' + ' ' * i
for i in range(height)
)
slash = stringPict(slash, height - 1)
#left half of root symbol
if height > 2:
downline = stringPict('\\ \n \\', 1)
else:
downline = stringPict('\\')
#put n on top, as low as possible
if n is not None and n.width() > downline.width():
downline = downline.left(' '*(n.width() - downline.width()))
downline = downline.above(n)
#build root symbol
root = downline.right(slash)
#glue it on at the proper height
#normally, the root symbel is as high as self
#which is one less than result
#this moves the root symbol one down
#if the root became higher, the baseline has to grow too
root.baseline = result.baseline - result.height() + root.height()
return result.left(root)
[docs] def render(self, * args, **kwargs):
"""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.
"""
if kwargs["wrap_line"] is False:
return "\n".join(self.picture)
if kwargs["num_columns"] is not None:
# Read the argument num_columns if it is not None
ncols = kwargs["num_columns"]
else:
# Attempt to get a terminal width
ncols = self.terminal_width()
ncols -= 2
if ncols <= 0:
ncols = 78
# If smaller than the terminal width, no need to correct
if self.width() <= ncols:
return type(self.picture[0])(self)
# for one-line pictures we don't need v-spacers. on the other hand, for
# multiline-pictures, we need v-spacers between blocks, compare:
#
# 2 2 3 | a*c*e + a*c*f + a*d | a*c*e + a*c*f + a*d | 3.14159265358979323
# 6*x *y + 4*x*y + | | *e + a*d*f + b*c*e | 84626433832795
# | *e + a*d*f + b*c*e | + b*c*f + b*d*e + b |
# 3 4 4 | | *d*f |
# 4*y*x + x + y | + b*c*f + b*d*e + b | |
# | | |
# | *d*f
i = 0
svals = []
do_vspacers = (self.height() > 1)
while i < self.width():
svals.extend([ sval[i:i + ncols] for sval in self.picture ])
if do_vspacers:
svals.append("") # a vertical spacer
i += ncols
if svals[-1] == '':
del svals[-1] # Get rid of the last spacer
return "\n".join(svals)
[docs] def terminal_width(self):
"""Return the terminal width if possible, otherwise return 0.
"""
ncols = 0
try:
import curses
import io
try:
curses.setupterm()
ncols = curses.tigetnum('cols')
except AttributeError:
# windows curses doesn't implement setupterm or tigetnum
# code below from
# http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/440694
from ctypes import windll, create_string_buffer
# stdin handle is -10
# stdout handle is -11
# stderr handle is -12
h = windll.kernel32.GetStdHandle(-12)
csbi = create_string_buffer(22)
res = windll.kernel32.GetConsoleScreenBufferInfo(h, csbi)
if res:
import struct
(bufx, bufy, curx, cury, wattr,
left, top, right, bottom, maxx, maxy) = struct.unpack("hhhhHhhhhhh", csbi.raw)
ncols = right - left + 1
except curses.error:
pass
except io.UnsupportedOperation:
pass
except (ImportError, TypeError):
pass
return ncols
def __eq__(self, o):
if isinstance(o, string_types):
return '\n'.join(self.picture) == o
elif isinstance(o, stringPict):
return o.picture == self.picture
return False
def __hash__(self):
return super(stringPict, self).__hash__()
def __str__(self):
return str.join('\n', self.picture)
def __unicode__(self):
return unicode.join(u'\n', self.picture)
def __repr__(self):
return "stringPict(%r,%d)" % ('\n'.join(self.picture), self.baseline)
def __getitem__(self, index):
return self.picture[index]
def __len__(self):
return len(self.s)
