"""
pyCONMIN - A variation of the pyCONMIN wrapper specificially designed to
work with sparse optimization problems.
"""
# Standard Python modules
import datetime
import os
import time
# External modules
import numpy as np
# Local modules
from ..pyOpt_optimizer import Optimizer
from ..pyOpt_utils import import_module
# import the compiled module
THIS_DIR = os.path.dirname(os.path.abspath(__file__))
conmin = import_module("conmin", [THIS_DIR])
[docs]
class CONMIN(Optimizer):
"""
CONMIN Optimizer Class - Inherited from Optimizer Abstract Class
"""
def __init__(self, raiseError=True, options={}):
name = "CONMIN"
category = "Local Optimizer"
defOpts = self._getDefaultOptions()
informs = self._getInforms()
if isinstance(conmin, Exception) and raiseError:
raise conmin
self.set_options = []
super().__init__(name, category, defaultOptions=defOpts, informs=informs, options=options)
# CONMIN needs Jacobians in dense format
self.jacType = "dense2d"
@staticmethod
def _getInforms():
informs = {}
return informs
@staticmethod
def _getDefaultOptions():
defOpts = {
"ITMAX": [int, int(1e4)],
"DELFUN": [float, 1e-6],
"DABFUN": [float, 1e-6],
"ITRM": [int, 5],
"NFEASCT": [int, 20],
"IPRINT": [int, 4],
"IOUT": [int, 6],
"IFILE": [str, "CONMIN.out"],
}
return defOpts
[docs]
def __call__(
self, optProb, sens=None, sensStep=None, sensMode=None, storeHistory=None, hotStart=None, storeSens=True
):
"""
This is the main routine used to solve the optimization
problem.
Parameters
----------
optProb : Optimization or Solution class instance
This is the complete description of the optimization problem
to be solved by the optimizer
sens : str or python Function.
Specifiy method to compute sensitivities. To
explictly use pyOptSparse gradient class to do the
derivatives with finite differenes use 'FD'. 'sens'
may also be 'CS' which will cause pyOptSpare to compute
the derivatives using the complex step method. Finally,
'sens' may be a python function handle which is expected
to compute the sensitivities directly. For expensive
function evaluations and/or problems with large numbers of
design variables this is the preferred method.
sensStep : float
Set the step size to use for design variables. Defaults to
1e-6 when sens is 'FD' and 1e-40j when sens is 'CS'.
sensMode : str
Use 'pgc' for parallel gradient computations. Only
available with mpi4py and each objective evaluation is
otherwise serial
storeHistory : str
File name of the history file into which the history of
this optimization will be stored
hotStart : str
File name of the history file to "replay" for the
optimziation. The optimization problem used to generate
the history file specified in 'hotStart' must be
**IDENTICAL** to the currently supplied 'optProb'. By
identical we mean, **EVERY SINGLE PARAMETER MUST BE
IDENTICAL**. As soon as he requested evaluation point
from CONMIN does not match the history, function and
gradient evaluations revert back to normal evaluations.
storeSens : bool
Flag sepcifying if sensitivities are to be stored in hist.
This is necessay for hot-starting only.
"""
self.startTime = time.time()
self.callCounter = 0
self.storeSens = storeSens
if len(optProb.constraints) == 0:
# If the user *actually* has an unconstrained problem,
# slsqp sort of chokes with that....it has to have at
# least one constraint. So we will add one
# automatically here:
self.unconstrained = True
optProb.dummyConstraint = True
# Save the optimization problem and finalize constraint
# Jacobian, in general can only do on root proc
self.optProb = optProb
self.optProb.finalize()
# Set history/hotstart/coldstart
self._setHistory(storeHistory, hotStart)
self._setInitialCacheValues()
self._setSens(sens, sensStep, sensMode)
blx, bux, xs = self._assembleContinuousVariables()
xs = np.maximum(xs, blx)
xs = np.minimum(xs, bux)
ff = self._assembleObjective()
oneSided = True
noEquality = True
if self.unconstrained:
m = 0
else:
indices, blc, buc, fact = self.optProb.getOrdering(
["ne", "le", "ni", "li"], oneSided=oneSided, noEquality=noEquality
)
m = len(indices)
self.optProb.jacIndices = indices
self.optProb.fact = fact
self.optProb.offset = buc
if self.optProb.comm.rank == 0:
# =================================================================
# CONMIN - Objective/Constraint Values Function
# =================================================================
def cnmnfun(n1, n2, x, f, g):
fobj, fcon, fail = self._masterFunc(x[0:ndv], ["fobj", "fcon"])
f = fobj
g[0:ncn] = fcon
return f, g
# =================================================================
# CONMIN - Objective/Constraint Gradients Function
# =================================================================
def cnmngrad(n1, n2, x, f, g, ct, df, a, ic, nac):
gobj, gcon, fail = self._masterFunc(x[0:ndv], ["gobj", "gcon"])
df[0:ndv] = gobj.copy()
# Only assign the gradients for constraints that are
# actually active:
nac = 0
for j in range(ncn):
if g[j] >= ct:
a[0:ndv, nac] = gcon[j, :]
ic[nac] = j + 1
nac += 1
return df, a, ic, nac
# Setup argument list values
ndv = len(xs)
ncn = m
nn1 = ndv + 2
nn2 = ncn + 2 * ndv
nn3 = max(nn2, ndv)
nn4 = max(nn2, ndv)
nn5 = 2 * nn4
if ncn > 0:
gg = np.zeros(ncn, float)
else:
gg = np.array([0], float)
if self.getOption("IPRINT") >= 0 and self.getOption("IPRINT") <= 4:
iprint = self.getOption("IPRINT")
else:
raise ValueError("IPRINT option must be >= 0 and <= 4")
iout = self.getOption("IOUT")
ifile = self.getOption("IFILE")
# Check if file exists and remove if necessary
if iprint > 0:
if os.path.isfile(ifile):
os.remove(ifile)
itmax = self.getOption("ITMAX")
delfun = self.getOption("DELFUN")
# finit, ginit = cnmnfun([],[],xx,ff,gg)
dabfun = self.getOption("DABFUN")
itrm = self.getOption("ITRM")
nfeasct = self.getOption("ITRM")
nfdg = 1 # User will supply all gradients
# Counters for functions and gradients
nfun = 0
ngrd = 0
# Run CONMIN
t0 = time.time()
# fmt: off
conmin.conmin(ndv, ncn, xs, blx, bux, ff, gg,
nn1, nn2, nn3, nn4, nn5,
iprint, iout, ifile, itmax, delfun, dabfun, itrm,
nfeasct, nfdg, nfun, ngrd, cnmnfun, cnmngrad)
# fmt: on
optTime = time.time() - t0
if self.storeHistory:
self.metadata["endTime"] = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
self.metadata["optTime"] = optTime
self.hist.writeData("metadata", self.metadata)
self.hist.close()
if iprint > 0:
conmin.closeunit(self.getOption("IOUT"))
# Broadcast a -1 to indcate SLSQP has finished
self.optProb.comm.bcast(-1, root=0)
# Optimizer has no exit conditions, so nothing to set
sol_inform = None
# Create the optimization solution
sol = self._createSolution(optTime, sol_inform, ff, xs)
else: # We are not on the root process so go into waiting loop:
self._waitLoop()
sol = None
# Communication solution and return
sol = self._communicateSolution(sol)
return sol