A python Non-Linear Programming API with Heuristic approach
Project description
flopt
A python Non-Linear Programming API with Heuristic approach.
Install
git clone https://github.com/flab-coder/flopt.git
Formulatable problems in flopt
-
Non-Linear problem (has no constrainets)
minimize 2*(3*a+b)*c**2 + 3 s.t 0 <= a <= 1 1 <= b <= 2 1 <= c <= 3
-
BlackBox problem
minimize simulator(a, b, c) s.t 0 <= a <= 1 1 <= b <= 2 1 <= c <= 3
-
Finding the best permutation problem ( including TSP)
-
Satisfiability problem (including MAX-SAT)
Heuristic Algorithms
- Random Search
- 2-Opt
- Swarm Intelligence Search
- Other applications
Simple Example
You can write codes like PuLP application.
from flopt import Variable, Problem, Solver
# Variables
a = Variable('a', lowBound=0, upBound=1, cat='Integer')
b = Variable('b', lowBound=1, upBound=2, cat='Continuous')
c = Variable('c', lowBound=1, upBound=3, cat='Continuous')
# Problem
prob = Problem()
prob += 2*(3*a+b)*c**2+3 # set the objective function
# Solver
solver = Solver(algo='RandomSearch') # select the heuristic algorithm
solver.setParams(n_trial=1000) # setting of the hyper parameters
prob.solve(solver, msg=True) # run solver to solve the problem
# display the result, incumbent solution
print('obj value', prob.getObjectiveValue())
print('a', a.value())
print('b', b.value())
print('c', c.value())
In addition, you can represent any objective function by CustomObject
from flopt import CustomObject
from math import sin, cos
def user_func(a, b, c):
return (0.7*a + 0.3*cos(b)**2 + 0.1*sin(c))*abs(c)
custom_obj = CustomObject(func=user_func, variables=[a, b, c])
prob = Problem(name='CustomObject')
prob += custom_obj
In the case you solve TSP, Permutation Variable is useful.
# Variables
perm = Variable('perm', lowBound=0, upBound=N-1, cat='Permutation')
# Object
def tsp_dist(perm):
distance = 0
for head, tail in zip(perm, perm[1:]+[perm[0]]):
distance += D[head][tail] # D is the distance matrix
return distance
tsp_obj = CustomObject(func=tsp_dist, variables=[perm])
# Problem
prob = Problem(name='TSP')
prob += tsp_obj
Project details
Release history Release notifications | RSS feed
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distributions
No source distribution files available for this release.See tutorial on generating distribution archives.