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"""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 .pretty_symbology import hobj, vobj, xsym, xobj, pretty_use_unicode, line_width
from sympy.utilities.exceptions import sympy_deprecation_warning
class stringPict:
"""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(line_width(line) for line in lines)
return [line.center(width) for line in lines]
def height(self):
"""The height of the picture in characters."""
return len(self.picture)
def width(self):
"""The width of the picture in characters."""
return line_width(self.picture[0])
@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, str):
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
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)
def left(self, *args):
"""Put pictures (left to right) at left.
Returns string, baseline arguments for stringPict.
"""
return stringPict.next(*(args + (self,)))
@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, str):
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
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
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
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)
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))
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)
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)
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
# https://code.activestate.com/recipes/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, str):
return '\n'.join(self.picture) == o
elif isinstance(o, stringPict):
return o.picture == self.picture
return False
def __hash__(self):
return super().__hash__()
def __str__(self):
return '\n'.join(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)
class prettyForm(stringPict):
"""
Extension of the stringPict class that knows about basic math applications,
optimizing double minus signs.
"Binding" is interpreted as follows::
ATOM this is an atom: never needs to be parenthesized
FUNC this is a function application: parenthesize if added (?)
DIV this is a division: make wider division if divided
POW this is a power: only parenthesize if exponent
MUL this is a multiplication: parenthesize if powered
ADD this is an addition: parenthesize if multiplied or powered
NEG this is a negative number: optimize if added, parenthesize if
multiplied or powered
OPEN this is an open object: parenthesize if added, multiplied, or
powered (example: Piecewise)
"""
ATOM, FUNC, DIV, POW, MUL, ADD, NEG, OPEN = range(8)
def __init__(self, s, baseline=0, binding=0, unicode=None):
"""Initialize from stringPict and binding power."""
stringPict.__init__(self, s, baseline)
self.binding = binding
if unicode is not None:
sympy_deprecation_warning(
"""
The unicode argument to prettyForm is deprecated. Only the s
argument (the first positional argument) should be passed.
""",
deprecated_since_version="1.7",
active_deprecations_target="deprecated-pretty-printing-functions")
self._unicode = unicode or s
@property
def unicode(self):
sympy_deprecation_warning(
"""
The prettyForm.unicode attribute is deprecated. Use the
prettyForm.s attribute instead.
""",
deprecated_since_version="1.7",
active_deprecations_target="deprecated-pretty-printing-functions")
return self._unicode
# Note: code to handle subtraction is in _print_Add
def __add__(self, *others):
"""Make a pretty addition.
Addition of negative numbers is simplified.
"""
arg = self
if arg.binding > prettyForm.NEG:
arg = stringPict(*arg.parens())
result = [arg]
for arg in others:
#add parentheses for weak binders
if arg.binding > prettyForm.NEG:
arg = stringPict(*arg.parens())
#use existing minus sign if available
if arg.binding != prettyForm.NEG:
result.append(' + ')
result.append(arg)
return prettyForm(binding=prettyForm.ADD, *stringPict.next(*result))
def __truediv__(self, den, slashed=False):
"""Make a pretty division; stacked or slashed.
"""
if slashed:
raise NotImplementedError("Can't do slashed fraction yet")
num = self
if num.binding == prettyForm.DIV:
num = stringPict(*num.parens())
if den.binding == prettyForm.DIV:
den = stringPict(*den.parens())
if num.binding==prettyForm.NEG:
num = num.right(" ")[0]
return prettyForm(binding=prettyForm.DIV, *stringPict.stack(
num,
stringPict.LINE,
den))
def __mul__(self, *others):
"""Make a pretty multiplication.
Parentheses are needed around +, - and neg.
"""
quantity = {
'degree': "\N{DEGREE SIGN}"
}
if len(others) == 0:
return self # We aren't actually multiplying... So nothing to do here.
# add parens on args that need them
arg = self
if arg.binding > prettyForm.MUL and arg.binding != prettyForm.NEG:
arg = stringPict(*arg.parens())
result = [arg]
for arg in others:
if arg.picture[0] not in quantity.values():
result.append(xsym('*'))
#add parentheses for weak binders
if arg.binding > prettyForm.MUL and arg.binding != prettyForm.NEG:
arg = stringPict(*arg.parens())
result.append(arg)
len_res = len(result)
for i in range(len_res):
if i < len_res - 1 and result[i] == '-1' and result[i + 1] == xsym('*'):
# substitute -1 by -, like in -1*x -> -x
result.pop(i)
result.pop(i)
result.insert(i, '-')
if result[0][0] == '-':
# if there is a - sign in front of all
# This test was failing to catch a prettyForm.__mul__(prettyForm("-1", 0, 6)) being negative
bin = prettyForm.NEG
if result[0] == '-':
right = result[1]
if right.picture[right.baseline][0] == '-':
result[0] = '- '
else:
bin = prettyForm.MUL
return prettyForm(binding=bin, *stringPict.next(*result))
def __repr__(self):
return "prettyForm(%r,%d,%d)" % (
'\n'.join(self.picture),
self.baseline,
self.binding)
def __pow__(self, b):
"""Make a pretty power.
"""
a = self
use_inline_func_form = False
if b.binding == prettyForm.POW:
b = stringPict(*b.parens())
if a.binding > prettyForm.FUNC:
a = stringPict(*a.parens())
elif a.binding == prettyForm.FUNC:
# heuristic for when to use inline power
if b.height() > 1:
a = stringPict(*a.parens())
else:
use_inline_func_form = True
if use_inline_func_form:
# 2
# sin + + (x)
b.baseline = a.prettyFunc.baseline + b.height()
func = stringPict(*a.prettyFunc.right(b))
return prettyForm(*func.right(a.prettyArgs))
else:
# 2 <-- top
# (x+y) <-- bot
top = stringPict(*b.left(' '*a.width()))
bot = stringPict(*a.right(' '*b.width()))
return prettyForm(binding=prettyForm.POW, *bot.above(top))
simpleFunctions = ["sin", "cos", "tan"]
@staticmethod
def apply(function, *args):
"""Functions of one or more variables.
"""
if function in prettyForm.simpleFunctions:
#simple function: use only space if possible
assert len(
args) == 1, "Simple function %s must have 1 argument" % function
arg = args[0].__pretty__()
if arg.binding <= prettyForm.DIV:
#optimization: no parentheses necessary
return prettyForm(binding=prettyForm.FUNC, *arg.left(function + ' '))
argumentList = []
for arg in args:
argumentList.append(',')
argumentList.append(arg.__pretty__())
argumentList = stringPict(*stringPict.next(*argumentList[1:]))
argumentList = stringPict(*argumentList.parens())
return prettyForm(binding=prettyForm.ATOM, *argumentList.left(function))