Files
edx-platform/common/lib/xmodule/xmodule/progress.py
Maxim Dorovkov 8702e40589 INCR-230 - Run python-modernize and isort on common/lib/xmodule/xmodule (#20506)
* INCR-230 - Run python-modernize and isort on common/lib/xmodule/xmodule, plus a few minor fixes suggested by Jeremy
2019-05-16 10:09:15 -04:00

137 lines
4.0 KiB
Python

'''
Progress class for modules. Represents where a student is in a module.
For most subclassing needs, you should only need to reimplement
frac() and __str__().
'''
from __future__ import absolute_import
import numbers
class Progress(object):
'''Represents a progress of a/b (a out of b done)
a and b must be numeric, but not necessarily integer, with
0 <= a <= b and b > 0.
Progress can only represent Progress for modules where that makes sense. Other
modules (e.g. html) should return None from get_progress().
TODO: add tag for module type? Would allow for smarter merging.
'''
def __init__(self, a, b):
'''Construct a Progress object. a and b must be numbers, and must have
0 <= a <= b and b > 0
'''
# Want to do all checking at construction time, so explicitly check types
if not (isinstance(a, numbers.Number) and
isinstance(b, numbers.Number)):
raise TypeError('a and b must be numbers. Passed {0}/{1}'.format(a, b))
if a > b:
a = b
if a < 0:
a = 0
if b <= 0:
raise ValueError('fraction a/b = {0}/{1} must have b > 0'.format(a, b))
self._a = a
self._b = b
def frac(self):
''' Return tuple (a,b) representing progress of a/b'''
return (self._a, self._b)
def percent(self):
''' Returns a percentage progress as a float between 0 and 100.
subclassing note: implemented in terms of frac(), assumes sanity
checking is done at construction time.
'''
(a, b) = self.frac()
return 100.0 * a / b
def started(self):
''' Returns True if fractional progress is greater than 0.
subclassing note: implemented in terms of frac(), assumes sanity
checking is done at construction time.
'''
return self.frac()[0] > 0
def inprogress(self):
''' Returns True if fractional progress is strictly between 0 and 1.
subclassing note: implemented in terms of frac(), assumes sanity
checking is done at construction time.
'''
(a, b) = self.frac()
return a > 0 and a < b
def done(self):
''' Return True if this represents done.
subclassing note: implemented in terms of frac(), assumes sanity
checking is done at construction time.
'''
(a, b) = self.frac()
return a == b
def ternary_str(self):
''' Return a string version of this progress: either
"none", "in_progress", or "done".
subclassing note: implemented in terms of frac()
'''
(a, b) = self.frac()
if a == 0:
return "none"
if a < b:
return "in_progress"
return "done"
def __eq__(self, other):
''' Two Progress objects are equal if they have identical values.
Implemented in terms of frac()'''
if not isinstance(other, Progress):
return False
(a, b) = self.frac()
(a2, b2) = other.frac()
return a == a2 and b == b2
def __ne__(self, other):
''' The opposite of equal'''
return not self.__eq__(other)
def __str__(self):
'''Return a string representation of this string. Rounds results to
two decimal places, stripping out any trailing zeroes.
subclassing note: implemented in terms of frac().
'''
(a, b) = self.frac()
display = lambda n: '{:.2f}'.format(n).rstrip('0').rstrip('.')
return "{0}/{1}".format(display(a), display(b))
@staticmethod
def add_counts(a, b):
'''Add two progress indicators, assuming that each represents items done:
(a / b) + (c / d) = (a + c) / (b + d).
If either is None, returns the other.
'''
if a is None:
return b
if b is None:
return a
# get numerators + denominators
(n, d) = a.frac()
(n2, d2) = b.frac()
return Progress(n + n2, d + d2)