def get_dist(archive, func, keymap=None):
"""get the graphical distance of func from data in archive
Args:
archive (klepto.archive): run archive (output of ``read``)
func (function): with interface ``y = f(x)``, ``x`` is a list of floats
keymap (klepto.keymap): keymap used for key encoding
Returns:
array of floats, graphical distance from func to each point in archive
"""
from mystic.math.legacydata import dataset
data = dataset()
arxiv = getattr(archive, '__archive__', archive)
if not len(arxiv):
return
#FIXME: need to implement generalized inverse of keymap
#HACK: only works in certain special cases
kind = getattr(keymap, '__stub__', '')
if kind in ('encoding', 'algorithm'): #FIXME always assumes used repr
inv = lambda k: eval(k)
elif kind in ('serializer', ): #FIXME: ignores all config options
import importlib
inv = lambda k: importlib.import_module(keymap.__type__).loads(k)
else: #FIXME: give up, ignore keymap
inv = lambda k: k
y = ((inv(k), v) for k, v in arxiv.items())
#HACK end
import numpy as np
y = np.array(list(y), dtype=object).T
data.load(y[0].tolist(), y[1].tolist(), ids=list(range(len(y[0]))))
from mystic.math.distance import graphical_distance
return graphical_distance(func, data)
def from_archive(cache, data=None, **kwds):
'''convert a klepto.archive to a mystic.math.legacydata.dataset
Inputs:
cache: a klepto.archive instance
data: a mystic.math.legacydata.dataset of i points, M inputs, N outputs
axis: int, the desired index the tuple-valued dataset [0,N]
ids: a list of ids for the data, or a function ids(x,y) to generate ids
'''
axis = kwds.get('axis', None)
ids = kwds.get('ids', _iargsort) #XXX: better None?
import numpy as np #FIXME: accept lipshitz coeffs as input
if data is None:
from mystic.math.legacydata import dataset
data = dataset()
# import klepto as kl
# ca = kl.archives.dir_archive('__objective_5D_cache__', cached=False)
# k = keymap=kl.keymaps.keymap()
# c = kl.inf_cache(keymap=k, tol=1, ignore=('**','out'), cache=ca)
# memo = c(lambda *args, **kwds: kwds['out'])
# cache = memo.__cache__()
y = np.array(list(cache.items()),
dtype=object).T #NOTE: cache.items() slow
if not len(y): return data
if callable(ids): #XXX: don't repeat tolist
ids = ids(y[0].tolist(), y[1].tolist(), axis=axis)
if axis is None: #XXX: dataset should be single valued
return data.load(y[0].tolist(), y[1].tolist(), ids=ids)
return data.load(y[0].tolist(), [i[axis] for i in y[1]], ids=ids)
def short_wrt_data(self, data, L=None, blamelist=False, pairs=True, \
all=False, raw=False, **kwds):
"""check for shortness with respect to the given data
Inputs:
data -- a collection of data points
L -- the lipschitz constant, if different from that provided with data
blamelist -- if True, report which points are infeasible
pairs -- if True, report indicies of infeasible points
all -- if True, report results for each point (opposed to all points)
raw -- if True, report numerical results (opposed to boolean results)
Additional Inputs:
tol -- maximum acceptable deviation from shortness
cutoff -- zero out distances less than cutoff; typically cutoff = tol or 0.0
Notes:
Each point x,y can be thought to have an associated double-cone with slope
equal to the lipschitz constant. Shortness with respect to another point is
defined by the first point not being inside the cone of the second. We can
allow for some error in shortness, a short tolerance 'tol', for which the
point x,y is some acceptable y-distance inside the cone. While very tightly
related, cutoff and tol play distinct roles; tol is subtracted from
calculation of the lipschitz_distance, while cutoff zeros out the value
of any element less than the cutoff.
"""
from mystic.math.legacydata import dataset
_self = dataset()
_self.load(self.positions, self.values)
_self.lipschitz = data.lipschitz
for i in range(len(_self)):
_self[i].id = i
return _self.short(data, L=L, blamelist=blamelist, pairs=pairs, \
all=all, raw=raw, **kwds)
def short_wrt_data(self, data, L=None, blamelist=False, pairs=True, \
all=False, raw=False, **kwds):
"""check for shortness with respect to the given data
Inputs:
data -- a collection of data points
L -- the lipschitz constant, if different from that provided with data
blamelist -- if True, report which points are infeasible
pairs -- if True, report indices of infeasible points
all -- if True, report results for each point (opposed to all points)
raw -- if True, report numerical results (opposed to boolean results)
Additional Inputs:
tol -- maximum acceptable deviation from shortness
cutoff -- zero out distances less than cutoff; typically cutoff = tol or 0.0
Notes:
Each point x,y can be thought to have an associated double-cone with slope
equal to the lipschitz constant. Shortness with respect to another point is
defined by the first point not being inside the cone of the second. We can
allow for some error in shortness, a short tolerance 'tol', for which the
point x,y is some acceptable y-distance inside the cone. While very tightly
related, cutoff and tol play distinct roles; tol is subtracted from
calculation of the lipschitz_distance, while cutoff zeros out the value
of any element less than the cutoff.
"""
from mystic.math.legacydata import dataset
_self = dataset()
_self.load(self.positions, self.values)
_self.lipschitz = data.lipschitz
for i in range(len(_self)):
_self[i].id = i
return _self.short(data, L=L, blamelist=blamelist, pairs=pairs, \
all=all, raw=raw, **kwds)
def cost(rv):
"""compute cost from a 1-d array of model parameters,
where: cost = | sum(lipschitz_distance) | """
_data = dataset()
_pm = scenario()
_pm.load(rv, pts) # here rv is param: w,x,y
if not long_form:
positions = _pm.select(*range(npts))
else: positions = _pm.positions
_data.load( data.coords, data.values ) # LOAD static
if _self:
_data.load( positions, _pm.values ) # LOAD dynamic
_data.lipschitz = data.lipschitz # LOAD L
Rv = lipschitz_distance(_data.lipschitz, _pm, _data, tol=cutoff, **kwds)
v = infeasibility(Rv, cutoff)
return abs(sum(v))
def cost(rv):
"""compute cost from a 1-d array of model parameters,
where: cost = | sum(lipschitz_distance) | """
_data = dataset()
_pm = scenario()
_pm.load(rv, pts) # here rv is param: w,x,y
if not long_form:
positions = _pm.select(*range(npts))
else: positions = _pm.positions
_data.load( data.coords, data.values ) # LOAD static
if _self:
_data.load( positions, _pm.values ) # LOAD dynamic
_data.lipschitz = data.lipschitz # LOAD L
Rv = lipschitz_distance(_data.lipschitz, _pm, _data, tol=cutoff, **kwds)
v = infeasibility(Rv, cutoff)
return abs(sum(v))
def _getitem(data, axis):
"""get the selected axis of the tuple-valued dataset
Inputs:
data: a mystic.math.legacydata.dataset of i points, M inputs, N outputs
axis: int, the desired index the tuple-valued dataset [0,N]
"""
if len(data.values) and type(data.values[0]) not in (tuple,list):
msg = "cannot get axis %s for single-valued dataset.values" % axis
raise ValueError(msg)
# assumes axis is an int; select values corresponding to axis
from mystic.math.legacydata import dataset, datapoint as datapt
ds = dataset()
for pt in data:
ds.append(datapt(pt.position, pt.value[axis], pt.id, pt.cone.slopes))
return ds
def valid_wrt_model(self, model, blamelist=False, pairs=True, \
all=False, raw=False, **kwds):
"""check for scenario validity with respect to the model
Inputs:
model -- the model function, y' = F(x')
blamelist -- if True, report which points are infeasible
pairs -- if True, report indicies of infeasible points
all -- if True, report results for each point (opposed to all points)
raw -- if True, report numerical results (opposed to boolean results)
Additional Inputs:
ytol -- maximum acceptable difference |y - F(x')|; a single value
xtol -- maximum acceptable difference |x - x'|; an iterable or single value
cutoff -- zero out distances less than cutoff; typically: ytol, 0.0, or None
hausdorff -- norm; where if given, ytol = |y - F(x')| + |x - x'|/norm
Notes:
xtol defines the n-dimensional base of a pilar of height ytol, centered at
each point. The region inside the pilar defines the space where a "valid"
model must intersect. If xtol is not specified, then the base of the pilar
will be a dirac at x' = x. This function performs an optimization for each
x to find an appropriate x'. While cutoff and ytol are very tightly related,
they play a distinct role; ytol is used to set the optimization termination
for an acceptable |y - F(x')|, while cutoff is applied post-optimization.
If we are using the hausdorff norm, then ytol will set the optimization
termination for an acceptable |y - F(x')| + |x - x'|/norm, where the x
values are normalized by norm = hausdorff.
"""
from mystic.math.legacydata import dataset
data = dataset()
data.load(self.positions, self.values)
#data.lipschitz = L
for i in range(len(data)):
data[i].id = i
return data.valid(model, blamelist=blamelist, pairs=pairs, \
all=all, raw=raw, **kwds)
def valid_wrt_model(self, model, blamelist=False, pairs=True, \
all=False, raw=False, **kwds):
"""check for scenario validity with respect to the model
Inputs:
model -- the model function, y' = F(x')
blamelist -- if True, report which points are infeasible
pairs -- if True, report indices of infeasible points
all -- if True, report results for each point (opposed to all points)
raw -- if True, report numerical results (opposed to boolean results)
Additional Inputs:
ytol -- maximum acceptable difference |y - F(x')|; a single value
xtol -- maximum acceptable difference |x - x'|; an iterable or single value
cutoff -- zero out distances less than cutoff; typically: ytol, 0.0, or None
hausdorff -- norm; where if given, ytol = |y - F(x')| + |x - x'|/norm
Notes:
xtol defines the n-dimensional base of a pilar of height ytol, centered at
each point. The region inside the pilar defines the space where a "valid"
model must intersect. If xtol is not specified, then the base of the pilar
will be a dirac at x' = x. This function performs an optimization for each
x to find an appropriate x'. While cutoff and ytol are very tightly related,
they play a distinct role; ytol is used to set the optimization termination
for an acceptable |y - F(x')|, while cutoff is applied post-optimization.
If we are using the hausdorff norm, then ytol will set the optimization
termination for an acceptable |y - F(x')| + |x - x'|/norm, where the x
values are normalized by norm = hausdorff.
"""
from mystic.math.legacydata import dataset
data = dataset()
data.load(self.positions, self.values)
#data.lipschitz = L
for i in range(len(data)):
data[i].id = i
return data.valid(model, blamelist=blamelist, pairs=pairs, \
all=all, raw=raw, **kwds)
def from_archive(cache, data=None, axis=None):
'''convert a klepto.archive to a mystic.math.legacydata.dataset
Inputs:
cache: a klepto.archive instance
data: a mystic.math.legacydata.dataset of i points, M inputs, N outputs
axis: int, the desired index the tuple-valued dataset [0,N]
'''
import numpy as np
if data is None:
from mystic.math.legacydata import dataset
data = dataset()
# import klepto as kl
# ca = kl.archives.dir_archive('__objective_5D_cache__', cached=False)
# k = keymap=kl.keymaps.keymap()
# c = kl.inf_cache(keymap=k, tol=1, ignore=('**','out'), cache=ca)
# memo = c(lambda *args, **kwds: kwds['out'])
# cache = memo.__cache__()
y = np.array(list(cache.items()), dtype=object).T #NOTE: cache.items() slow
if not len(y): return data
ids = list(range(len(y[0])))
if axis is None: #XXX: dataset should be single valued
return data.load(y[0].tolist(), y[1].tolist(), ids=ids)
return data.load(y[0].tolist(), [i[axis] for i in y[1]], ids=ids)
def graphical_distance(model, points, **kwds):
"""find the radius(x') that minimizes the graph between reality, y = G(x),
and an approximating function, y' = F(x')
Inputs:
model = the model function, y' = F(x'), that approximates reality, y = G(x)
points = object of type 'datapoint' to validate against; defines y = G(x)
Additional Inputs:
ytol = maximum acceptable difference |y - F(x')|; a single value
xtol = maximum acceptable difference |x - x'|; an iterable or single value
cutoff = zero out distances less than cutoff; typically: ytol, 0.0, or None
hausdorff = norm; where if given, ytol = |y - F(x')| + |x - x'|/norm
Returns:
radius = minimum distance from x,G(x) to x',F(x') for each x
Notes:
xtol defines the n-dimensional base of a pilar of height ytol, centered at
each point. The region inside the pilar defines the space where a "valid"
model must intersect. If xtol is not specified, then the base of the pilar
will be a dirac at x' = x. This function performs an optimization for each
x to find an appropriate x'. While cutoff and ytol are very tightly related,
they play a distinct role; ytol is used to set the optimization termination
for an acceptable |y - F(x')|, while cutoff is applied post-optimization.
If we are using the hausdorff norm, then ytol will set the optimization
termination for an acceptable |y - F(x')| + |x - x'|/norm, where the x
values are normalized by norm = hausdorff.
""" #FIXME: update docs to show normalization in y
#NotImplemented:
#L = list of lipschitz constants, for use when lipschitz metric is desired
#constraints = constraints function for finding minimum distance
from mystic.math.legacydata import dataset
from numpy import asarray, sum, isfinite, zeros, seterr
from mystic.solvers import diffev2, fmin_powell
from mystic.monitors import Monitor, VerboseMonitor
# ensure target xe and ye is a dataset
target = dataset()
target.load(*_get_xy(points))
nyi = target.npts # y's are target.values
nxi = len(target.coords[-1]) # nxi = len(x) / len(y)
# NOTE: the constraints function is a function over a single xe,ye
# because each underlying optimization is over a single xe,ye.
# thus, we 'pass' on using constraints at this time...
constraints = None # default is no constraints
if 'constraints' in kwds: constraints = kwds.pop('constraints')
if not constraints: # if None (default), there are no constraints
constraints = lambda x: x
# get tolerance in y and wiggle room in x
ytol = kwds.pop('ytol', 0.0)
xtol = kwds.pop('xtol', 0.0) # default is to not allow 'wiggle room' in x
cutoff = ytol # default is to zero out distances less than tolerance
if 'cutoff' in kwds: cutoff = kwds.pop('cutoff')
if cutoff is True: cutoff = ytol
elif cutoff is False: cutoff = None
ipop = kwds.pop('ipop', min(20, 3*nxi)) #XXX: tune ipop?
imax = kwds.pop('imax', 1000) #XXX: tune imax?
# get range for the dataset (normalization for hausdorff distance)
hausdorff = kwds.pop('hausdorff', False)
if not hausdorff: # False, (), None, ...
ptp = [0.0]*nxi
yptp = 1.0
elif hausdorff is True:
from mystic.math.measures import spread
ptp = [spread(xi) for xi in zip(*target.coords)]
yptp = spread(target.values) #XXX: this can lead to bad bad things...
else:
try: #iterables
if len(hausdorff) < nxi+1:
hausdorff = list(hausdorff) + [0.0]*(nxi - len(hausdorff)) + [1.0]
ptp = hausdorff[:-1] # all the x
yptp = hausdorff[-1] # just the y
except TypeError: #non-iterables
ptp = [hausdorff]*nxi
yptp = hausdorff
#########################################################################
def radius(model, point, ytol=0.0, xtol=0.0, ipop=None, imax=None):
"""graphical distance between a single point x,y and a model F(x')"""
# given a single point x,y: find the radius = |y - F(x')| + delta
# radius is just a minimization over x' of |y - F(x')| + delta
# where we apply a constraints function (of box constraints) of
# |x - x'| <= xtol (for each i in x)
#
# if hausdorff = some iterable, delta = |x - x'|/hausdorff
# if hausdorff = True, delta = |x - x'|/spread(x); using the dataset range
# if hausdorff = False, delta = 0.0
#
# if ipop, then DE else Powell; ytol is used in VTR(ytol)
# and will terminate when cost <= ytol
x,y = _get_xy(point)
y = asarray(y)
# catch cases where yptp or y will cause issues in normalization
#if not isfinite(yptp): return 0.0 #FIXME: correct? shouldn't happen
#if yptp == 0: from numpy import inf; return inf #FIXME: this is bad
# build the cost function
if hausdorff: # distance in all directions
def cost(rv):
'''cost = |y - F(x')| + |x - x'| for each x,y (point in dataset)'''
_y = model(rv)
if not isfinite(_y): return abs(_y)
errs = seterr(invalid='ignore', divide='ignore') # turn off warning
z = abs((asarray(x) - rv)/ptp) # normalize by range
m = abs(y - _y)/yptp # normalize by range
seterr(invalid=errs['invalid'], divide=errs['divide']) # turn on warning
return m + sum(z[isfinite(z)])
else: # vertical distance only
def cost(rv):
'''cost = |y - F(x')| for each x,y (point in dataset)'''
return abs(y - model(rv))
if debug:
print("rv: %s" % str(x))
print("cost: %s" % cost(x))
# if xtol=0, radius is difference in x,y and x,F(x); skip the optimization
try:
if not imax or not max(xtol): #iterables
return cost(x)
except TypeError:
if not xtol: #non-iterables
return cost(x)
# set the range constraints
xtol = asarray(xtol)
bounds = list(zip( x - xtol, x + xtol ))
if debug:
print("lower: %s" % str(zip(*bounds)[0]))
print("upper: %s" % str(zip(*bounds)[1]))
# optimize where initially x' = x
stepmon = Monitor()
if debug: stepmon = VerboseMonitor(1)
#XXX: edit settings?
MINMAX = 1 #XXX: confirm MINMAX=1 is minimization
ftol = ytol
gtol = None # use VTRCOG
if ipop:
results = diffev2(cost, bounds, ipop, ftol=ftol, gtol=gtol, \
itermon = stepmon, maxiter=imax, bounds=bounds, \
full_output=1, disp=0, handler=False)
else:
results = fmin_powell(cost, x, ftol=ftol, gtol=gtol, \
itermon = stepmon, maxiter=imax, bounds=bounds, \
full_output=1, disp=0, handler=False)
#solved = results[0] # x'
func_opt = MINMAX * results[1] # cost(x')
if debug:
print("solved: %s" % results[0])
print("cost: %s" % func_opt)
# get the minimum distance |y - F(x')|
return func_opt
#return results[0], func_opt
#########################################################################
#XXX: better to do a single optimization rather than for each point ???
d = [radius(model, point, ytol, xtol, ipop, imax) for point in target]
return infeasibility(d, cutoff)
pm = scenario()
pm.load(param1, pts)
print("pm.wts: %s" % str(pm.wts))
print("pm.pos: %s" % str(pm.pos))
W = pm.weights
X = pm.coords
Y = pm.values
print("pm.weights: %s" % str(W))
print("pm.coords: %s" % str(X))
print("pm.values: %s" % str(Y))
print("\nbuilding a dataset from the scenario...")
# build a dataset (using X,Y)
# [store W as 'weights' ?]
from mystic.math.legacydata import dataset
d = dataset()
d.load(X, Y)
print("d.coords: %s" % str(d.coords))
print("d.values: %s" % str(d.values))
print("\nedit the dataset...")
d[0].value = 0
print("d.values: %s" % str(d.values))
# DON'T EDIT d[0].position... IT BREAKS PRODUCT MEASURE!!!
print("\nupdate the scenario from the dataset...")
# update pm(w,x,Y | W,X) from dataset(X,Y)
pm.coords, pm.values = d.fetch()
print("then, build a new list of params from the scenario...")
# convert pm(w,x,Y | W,X) to params(w,x,Y)
param1 = pm.flatten(all=True)
filter = None
try: # select the scenario dimensions
npts = eval(parsed_opts.dim) # format is "(1,1,1)"
if npts is None: # npts may have been logged
exec "from %s import npts" % file
except:
npts = (1,1,1) #XXX: better in parsed_args ?
try: # get the name of the dataset file
file = parsed_args[1]
from mystic.math.legacydata import load_dataset
data = load_dataset(file, filter)
except:
# raise IOError, "please provide dataset file name"
data = dataset()
cones = False
legacy = False
try: # select the bounds
_bounds = parsed_opts.bounds
if _bounds[-1] == "*": #XXX: then bounds are NOT strictly enforced
_bounds = _bounds[:-1]
strict = False
else:
strict = True
bounds = eval(_bounds) # format is "[(60,105),(0,30),(2.1,2.8)]"
except:
strict = True
bounds = [(0,1),(0,1),(0,1)]
filter = None
try: # select the scenario dimensions
npts = eval(parsed_opts.dim) # format is "(1,1,1)"
if npts is None: # npts may have been logged
exec "from %s import npts" % file
except:
npts = (1, 1, 1) #XXX: better in parsed_args ?
try: # get the name of the dataset file
file = parsed_args[1]
from mystic.math.legacydata import load_dataset
data = load_dataset(file, filter)
except:
# raise IOError, "please provide dataset file name"
data = dataset()
cones = False
legacy = False
try: # select the bounds
_bounds = parsed_opts.bounds
if _bounds[-1] == "*": #XXX: then bounds are NOT strictly enforced
_bounds = _bounds[:-1]
strict = False
else:
strict = True
bounds = eval(_bounds) # format is "[(60,105),(0,30),(2.1,2.8)]"
except:
strict = True
bounds = [(0, 1), (0, 1), (0, 1)]
pm = scenario()
pm.load(param1, pts)
print("pm.wts: %s" % str(pm.wts))
print("pm.pos: %s" % str(pm.pos))
W = pm.weights
X = pm.coords
Y = pm.values
print("pm.weights: %s" % str(W))
print("pm.coords: %s" % str(X))
print("pm.values: %s" % str(Y))
print("\nbuilding a dataset from the scenario...")
# build a dataset (using X,Y)
# [store W as 'weights' ?]
from mystic.math.legacydata import dataset
d = dataset()
d.load(X, Y)
print("d.coords: %s" % str(d.coords))
print("d.values: %s" % str(d.values))
print("\nedit the dataset...")
d[0].value = 0
print("d.values: %s" % str(d.values))
# DON'T EDIT d[0].position... IT BREAKS PRODUCT MEASURE!!!
print("\nupdate the scenario from the dataset...")
# update pm(w,x,Y | W,X) from dataset(X,Y)
pm.coords, pm.values = d.fetch()
print("then, build a new list of params from the scenario...")
# convert pm(w,x,Y | W,X) to params(w,x,Y)
param1 = pm.flatten(all=True)
dirac_measure = measure if __name__ == '__main__': from mystic.math.distance import * model = lambda x:sum(x) a = [0,1,9,8, 1,0,4,6, 1,0,1,2, 0,1,2,3,4,5,6,7] feasability = 0.0; deviation = 0.01 validity = 5.0; wiggle = 1.0 y_mean = 5.0; y_buffer = 0.0 L = [.75,.5,.25] bc = [(0,7,2),(3,0,2),(2,0,3),(1,0,3),(2,4,2)] bv = [5,3,1,4,8] pts = (2,2,2) from mystic.math.legacydata import dataset data = dataset() data.load(bc, bv) data.lipschitz = L pm = scenario() pm.load(a, pts) pc = pm.positions pv = pm.values #--- _data = dataset() _data.load(bc, bv) _data.load(pc, pv) _data.lipschitz = data.lipschitz from numpy import sum ans = sum(lipschitz_distance(L, pm, _data)) print "original: %s @ %s\n" % (ans, a) #print "pm: %s" % pm
def graphical_distance(model, points, **kwds):
"""find the ``radius(x')`` that minimizes the graph between reality (data),
``y = G(x)``, and an approximating function, ``y' = F(x')``.
Args:
model (func): a model ``y' = F(x')`` that approximates reality ``y = G(x)``
points (mystic.math.legacydata.dataset): a dataset, defines ``y = G(x)``
ytol (float, default=0.0): maximum acceptable difference ``|y - F(x')|``.
xtol (float, default=0.0): maximum acceptable difference ``|x - x'|``.
cutoff (float, default=ytol): zero out distances less than cutoff.
hausdorff (bool, default=False): hausdorff ``norm``, where if given,
then ``ytol = |y - F(x')| + |x - x'|/norm``.
Returns:
the radius (the minimum distance ``x,G(x)`` to ``x',F(x')`` for each ``x``)
Notes:
*points* can be a ``mystic.math.legacydata.dataset`` or a list of
``mystic.math.legacydata.datapoint`` objects.
*xtol* defines the n-dimensional base of a pilar of height *ytol*,
centered at each point. The region inside the pilar defines the space
where a "valid" model must intersect. If *xtol* is not specified, then
the base of the pilar will be a dirac at ``x' = x``. This function
performs an optimization for each ``x`` to find an appropriate ``x'``.
*ytol* is a single value, while *xtol* is a single value or an iterable.
*cutoff* takes a float or a boolean, where ``cutoff=True`` will set the
value of *cutoff* to the default. Typically, the value of *cutoff* is
*ytol*, 0.0, or None. *hausdorff* can be False (e.g. ``norm = 1.0``),
True (e.g. ``norm = spread(x)``), or a list of points of ``len(x)``.
While *cutoff* and *ytol* are very tightly related, they play a distinct
role; *ytol* is used to set the optimization termination for an acceptable
``|y - F(x')|``, while *cutoff* is applied post-optimization.
If we are using the hausdorff norm, then *ytol* will set the optimization
termination for an acceptable ``|y - F(x')| + |x - x'|/norm``, where the
``x`` values are normalized by ``norm = hausdorff``.
""" #FIXME: update docs to show normalization in y
#NotImplemented:
#L = list of lipschitz constants, for use when lipschitz metric is desired
#constraints = constraints function for finding minimum distance
from mystic.math.legacydata import dataset
from numpy import asarray, sum, isfinite, zeros, seterr
from mystic.solvers import diffev2, fmin_powell
from mystic.monitors import Monitor, VerboseMonitor
# ensure target xe and ye is a dataset
target = dataset()
target.load(*_get_xy(points))
nyi = target.npts # y's are target.values
nxi = len(target.coords[-1]) # nxi = len(x) / len(y)
# NOTE: the constraints function is a function over a single xe,ye
# because each underlying optimization is over a single xe,ye.
# thus, we 'pass' on using constraints at this time...
constraints = None # default is no constraints
if 'constraints' in kwds: constraints = kwds.pop('constraints')
if not constraints: # if None (default), there are no constraints
constraints = lambda x: x
# get tolerance in y and wiggle room in x
ytol = kwds.pop('ytol', 0.0)
xtol = kwds.pop('xtol', 0.0) # default is to not allow 'wiggle room' in x
cutoff = ytol # default is to zero out distances less than tolerance
if 'cutoff' in kwds: cutoff = kwds.pop('cutoff')
if cutoff is True: cutoff = ytol
elif cutoff is False: cutoff = None
ipop = kwds.pop('ipop', min(20, 3*nxi)) #XXX: tune ipop?
imax = kwds.pop('imax', 1000) #XXX: tune imax?
# get range for the dataset (normalization for hausdorff distance)
hausdorff = kwds.pop('hausdorff', False)
if not hausdorff: # False, (), None, ...
ptp = [0.0]*nxi
yptp = 1.0
elif hausdorff is True:
from mystic.math.measures import spread
ptp = [spread(xi) for xi in zip(*target.coords)]
yptp = spread(target.values) #XXX: this can lead to bad bad things...
else:
try: #iterables
if len(hausdorff) < nxi+1:
hausdorff = list(hausdorff) + [0.0]*(nxi - len(hausdorff)) + [1.0]
ptp = hausdorff[:-1] # all the x
yptp = hausdorff[-1] # just the y
except TypeError: #non-iterables
ptp = [hausdorff]*nxi
yptp = hausdorff
#########################################################################
def radius(model, point, ytol=0.0, xtol=0.0, ipop=None, imax=None):
"""graphical distance between a single point x,y and a model F(x')"""
# given a single point x,y: find the radius = |y - F(x')| + delta
# radius is just a minimization over x' of |y - F(x')| + delta
# where we apply a constraints function (of box constraints) of
# |x - x'| <= xtol (for each i in x)
#
# if hausdorff = some iterable, delta = |x - x'|/hausdorff
# if hausdorff = True, delta = |x - x'|/spread(x); using the dataset range
# if hausdorff = False, delta = 0.0
#
# if ipop, then DE else Powell; ytol is used in VTR(ytol)
# and will terminate when cost <= ytol
x,y = _get_xy(point)
y = asarray(y)
# catch cases where yptp or y will cause issues in normalization
#if not isfinite(yptp): return 0.0 #FIXME: correct? shouldn't happen
#if yptp == 0: from numpy import inf; return inf #FIXME: this is bad
# build the cost function
if hausdorff: # distance in all directions
def cost(rv):
'''cost = |y - F(x')| + |x - x'| for each x,y (point in dataset)'''
_y = model(rv)
if not isfinite(_y): return abs(_y)
errs = seterr(invalid='ignore', divide='ignore') # turn off warning
z = abs((asarray(x) - rv)/ptp) # normalize by range
m = abs(y - _y)/yptp # normalize by range
seterr(invalid=errs['invalid'], divide=errs['divide']) # turn on warning
return m + sum(z[isfinite(z)])
else: # vertical distance only
def cost(rv):
'''cost = |y - F(x')| for each x,y (point in dataset)'''
return abs(y - model(rv))
if debug:
print("rv: %s" % str(x))
print("cost: %s" % cost(x))
# if xtol=0, radius is difference in x,y and x,F(x); skip the optimization
try:
if not imax or not max(xtol): #iterables
return cost(x)
except TypeError:
if not xtol: #non-iterables
return cost(x)
# set the range constraints
xtol = asarray(xtol)
bounds = list(zip( x - xtol, x + xtol ))
if debug:
print("lower: %s" % str(zip(*bounds)[0]))
print("upper: %s" % str(zip(*bounds)[1]))
# optimize where initially x' = x
stepmon = Monitor()
if debug: stepmon = VerboseMonitor(1)
#XXX: edit settings?
MINMAX = 1 #XXX: confirm MINMAX=1 is minimization
ftol = ytol
gtol = None # use VTRCOG
if ipop:
results = diffev2(cost, bounds, ipop, ftol=ftol, gtol=gtol, \
itermon = stepmon, maxiter=imax, bounds=bounds, \
full_output=1, disp=0, handler=False)
else:
results = fmin_powell(cost, x, ftol=ftol, gtol=gtol, \
itermon = stepmon, maxiter=imax, bounds=bounds, \
full_output=1, disp=0, handler=False)
#solved = results[0] # x'
func_opt = MINMAX * results[1] # cost(x')
if debug:
print("solved: %s" % results[0])
print("cost: %s" % func_opt)
# get the minimum distance |y - F(x')|
return func_opt
#return results[0], func_opt
#########################################################################
#XXX: better to do a single optimization rather than for each point ???
d = [radius(model, point, ytol, xtol, ipop, imax) for point in target]
return infeasibility(d, cutoff)
dirac_measure = measure if __name__ == '__main__': from mystic.math.distance import * model = lambda x:sum(x) a = [0,1,9,8, 1,0,4,6, 1,0,1,2, 0,1,2,3,4,5,6,7] feasability = 0.0; deviation = 0.01 validity = 5.0; wiggle = 1.0 y_mean = 5.0; y_buffer = 0.0 L = [.75,.5,.25] bc = [(0,7,2),(3,0,2),(2,0,3),(1,0,3),(2,4,2)] bv = [5,3,1,4,8] pts = (2,2,2) from mystic.math.legacydata import dataset data = dataset() data.load(bc, bv) data.lipschitz = L pm = scenario() pm.load(a, pts) pc = pm.positions pv = pm.values #--- _data = dataset() _data.load(bc, bv) _data.load(pc, pv) _data.lipschitz = data.lipschitz from numpy import sum ans = sum(lipschitz_distance(L, pm, _data)) print "original: %s @ %s\n" % (ans, a) #print "pm: %s" % pm
