# PuLP Release 1.6.9

PuLP is an LP modeler written in python. PuLP can generate MPS or LP files and call GLPK, COIN CLP/CBC, CPLEX, and GUROBI to solve linear problems.

Keywords
Optimization
Other
Install
``` pip install PuLP==1.6.9 ```

# pulp

PuLP is an LP modeler written in python. PuLP can generate MPS or LP files and call GLPK[1], COIN CLP/CBC[2], CPLEX[3], and GUROBI[4] to solve linear problems.

## Installation

The easiest way to install pulp is via PyPi

If pip is available on your system

`````` \$pip install pulp
``````

Otherwise follow the download instructions on the PyPi page On Linux and OSX systems the tests must be run to make the default solver executable.

`````` \$sudo pulptest
``````

## Examples

See the examples directory for examples.

PuLP requires Python >= 2.6.

The examples use the default solver (cbc), to use other solvers they must be available.

# Documentation

Documentation is found on https://pythonhosted.org/PuLP/.

Use LpVariable() to create new variables. To create a variable 0 <= x <= 3

`````` >>> x = LpVariable("x", 0, 3)
``````

To create a variable 0 <= y <= 1

`````` >>> y = LpVariable("y", 0, 1)
``````

Use LpProblem() to create new problems. Create "myProblem"

`````` >>> prob = LpProblem("myProblem", LpMinimize)
``````

Combine variables to create expressions and constraints and add them to the problem.

`````` >>> prob += x + y <= 2
``````

If you add an expression (not a constraint), it will become the objective.

`````` >>> prob += -4*x + y
``````

To solve with the default included solver

`````` >>> status = prob.solve()
``````

To use another sovler to solve the problem.

`````` >>> status = prob.solve(GLPK(msg = 0))
``````

Display the status of the solution

`````` >>> LpStatus[status]
'Optimal'
``````

You can get the value of the variables using value(). ex:

`````` >>> value(x)
2.0
``````

Exported Classes:

• LpProblem -- Container class for a Linear programming problem

• LpVariable -- Variables that are added to constraints in the LP

• LpConstraint -- A constraint of the general form

``````a1x1+a2x2 ...anxn (<=, =, >=) b
``````
• LpConstraintVar -- Used to construct a column of the model in column-wise modelling

Exported Functions:

• value() -- Finds the value of a variable or expression
• lpSum() -- given a list of the form [a1*x1, a2x2, ..., anxn] will construct a linear expression to be used as a constraint or variable
• lpDot() --given two lists of the form [a1, a2, ..., an] and [ x1, x2, ..., xn] will construct a linear epression to be used as a constraint or variable

`````` Copyright J.S. Roy (js@jeannot.org), 2003-2005