`pulp.constants`

This file contains the constant definitions for PuLP Note that hopefully these will be changed into something more pythonic

class pulp.constants.LpSolveStatus(*values)

Bases: IntEnum

Why the solver stopped.

Whether a feasible solution came back is recorded separately, as has_solution.

GapLimit = -7: gap tolerance met, or an objective cutoff, bound or target reached

Infeasible = -1

Interrupted = -10: stopped by the user or an abort

IterationLimit = -8

MemoryLimit = -5

NodeLimit = -6

NotSolved = 0

NumericalError = -12: numerical trouble, or tolerances could not be met

Optimal = 1

SolutionLimit = -9

Stopped = -11: stopped early for a reason the solver does not report

TimeLimit = -4: time budget exhausted, including deterministic work limits

Unbounded = -2

Undefined = -3: the solver ran but its answer is inconclusive, e.g. infeasible or unbounded

as_integer_ratio()

Return a pair of integers, whose ratio is equal to the original int.

The ratio is in lowest terms and has a positive denominator.

>>> (10).as_integer_ratio()
(10, 1)
>>> (-10).as_integer_ratio()
(-10, 1)
>>> (0).as_integer_ratio()
(0, 1)

bit_count()

Number of ones in the binary representation of the absolute value of self.

Also known as the population count.

>>> bin(13)
'0b1101'
>>> (13).bit_count()
3

bit_length()

Number of bits necessary to represent self in binary.

>>> bin(37)
'0b100101'
>>> (37).bit_length()
6

conjugate(): Returns self, the complex conjugate of any int.

denominator: the denominator of a rational number in lowest terms

classmethod from_bytes(bytes, byteorder='big', *, signed=False)

Return the integer represented by the given array of bytes.

bytes: Holds the array of bytes to convert. The argument must either support the buffer protocol or be an iterable object producing bytes. Bytes and bytearray are examples of built-in objects that support the buffer protocol.
byteorder: The byte order used to represent the integer. If byteorder is ‘big’, the most significant byte is at the beginning of the byte array. If byteorder is ‘little’, the most significant byte is at the end of the byte array. To request the native byte order of the host system, use `sys.byteorder’ as the byte order value. Default is to use ‘big’.
signed: Indicates whether two’s complement is used to represent the integer.

imag: the imaginary part of a complex number

is_integer(): Returns True. Exists for duck type compatibility with float.is_integer.

numerator: the numerator of a rational number in lowest terms

real: the real part of a complex number

to_bytes(length=1, byteorder='big', *, signed=False)

Return an array of bytes representing an integer.

length: Length of bytes object to use. An OverflowError is raised if the integer is not representable with the given number of bytes. Default is length 1.
byteorder: The byte order used to represent the integer. If byteorder is ‘big’, the most significant byte is at the beginning of the byte array. If byteorder is ‘little’, the most significant byte is at the end of the byte array. To request the native byte order of the host system, use `sys.byteorder’ as the byte order value. Default is to use ‘big’.
signed: Determines whether two’s complement is used to represent the integer. If signed is False and a negative integer is given, an OverflowError is raised.

exception pulp.constants.PulpError

Bases: Exception

Pulp Exception Class

add_note(): Exception.add_note(note) – add a note to the exception

args

with_traceback(): Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

pulp.constants.LpContinuous: LpContinuous= “Continuous”

LpInteger = "Integer": LpInteger= “Integer”

LpBinary = "Binary": LpBinary= “Binary”

class pulp.constants.LpSolveStatus

Why the solver stopped, as stored in pulp.LpSolveStats.status – the type every solve returns. It is an IntEnum. Whether the solver handed back a feasible solution is kept separately, in pulp.LpSolveStats.has_solution.

member

meaning

numerical value

LpSolveStatus.Optimal

proven optimal

1

LpSolveStatus.NotSolved

not solved yet

0

LpSolveStatus.Infeasible

proven infeasible

-1

LpSolveStatus.Unbounded

proven unbounded

-2

LpSolveStatus.Undefined

inconclusive, e.g. infeasible or unbounded

-3

LpSolveStatus.TimeLimit

time (or deterministic work) limit

-4

LpSolveStatus.MemoryLimit

memory limit

-5

LpSolveStatus.NodeLimit

branch and bound node limit

-6

LpSolveStatus.GapLimit

gap tolerance, or objective cutoff/target

-7

LpSolveStatus.IterationLimit

iteration limit

-8

LpSolveStatus.SolutionLimit

number of solutions found

-9

LpSolveStatus.Interrupted

user interrupt or abort

-10

LpSolveStatus.Stopped

stopped early, the solver does not say why

-11

LpSolveStatus.NumericalError

numerical trouble

-12

pulp.constants.LpSenses

Dictionary of values for sense:

LpSenses = {LpMaximize:”Maximize”, LpMinimize:”Minimize”}

pulp.constants.LpMinimize

LpMinimize = 1

pulp.constants.LpMaximize

LpMaximize = -1

pulp.constants.LpConstraintEQ

LpConstraintEQ = 0

pulp.constants.LpConstraintLE

LpConstraintLE = -1

pulp.constants.LpConstraintGE

LpConstraintGE = 1

pulp.constants.LpConstraintSenses

LpConstraint key

symbolic value

numerical value

LpConstraintEQ

“==”

0

LpConstraintLE

“<=”

-1

LpConstraintGE

“>=”

1

pulp.constants

`pulp.constants`