gpkit.tools package¶

Submodules¶

gpkit.tools.autosweep module¶

Tools for optimal fits to GP sweeps

class gpkit.tools.autosweep.BinarySweepTree(bounds, sols, sweptvar, costposy)¶

Bases: object

Spans a line segment. May contain two subtrees that divide the segment.

bounds : two-element list: The left and right boundaries of the segment
sols : two-element list: The left and right solutions of the segment
costs : array: The left and right logcosts of the segment
splits : None or two-element list: If not None, contains the left and right subtrees
splitval : None or float: The worst-error point, where the split will be if tolerance is too low
splitlb : None or float: The cost lower bound at splitval
splitub : None or float: The cost upper bound at splitval

add_split(splitval, splitsol)¶: Creates subtrees from bounds[0] to splitval and splitval to bounds[1]

add_splitcost(splitval, splitlb, splitub)¶: Adds a splitval, lower bound, and upper bound

cost_at(_, value, bound=None)¶: Logspace interpolates between split and costs. Guaranteed bounded.

min_bst(value)¶: Returns smallest bst around value.

posy_at(posy, value)¶

Logspace interpolates between sols to get posynomial values.

No guarantees, just like a regular sweep.

sample_at(values)¶: Creates a SolutionOracle at a given range of values

save(filename='autosweep.p')¶

Pickles the autosweep and saves it to a file.

The saved autosweep is identical except for two things:

the cost is made unitless
each solution’s ‘program’ attribute is removed

Solution can then be loaded with e.g.:

>>> import cPickle as pickle
>>> pickle.load(open("autosweep.p"))

solarray¶: Returns a solution array of all the solutions in an autosweep

sollist¶: Returns a list of all the solutions in an autosweep

class gpkit.tools.autosweep.SolutionOracle(bst, sampled_at)¶

Bases: object

Acts like a SolutionArray for autosweeps

cost_lb()¶: Gets cost lower bounds from the BST and units them

cost_ub()¶: Gets cost upper bounds from the BST and units them

plot(posys=None, axes=None)¶: Plots the sweep for each posy

gpkit.tools.autosweep.autosweep_1d(model, logtol, sweepvar, bounds, **solvekwargs)¶: Autosweep a model over one sweepvar

gpkit.tools.autosweep.get_tol(costs, bounds, sols, variable)¶: Gets the intersection point and corresponding bounds from two solutions.

gpkit.tools.autosweep.recurse_splits(model, bst, variable, logtol, solvekwargs, sols)¶: Recursively splits a BST until logtol is reached

gpkit.tools.docstring module¶

Docstring-parsing methods

gpkit.tools.docstring.check_and_parse_flag(string, flag, errorcatch, declaration_func=None)¶: Checks for instances of flag in string and parses them.

gpkit.tools.docstring.constant_declare(string, flag, idx2, countstr)¶: Turns Variable declarations into Constant ones

gpkit.tools.docstring.expected_unbounded(instance, doc)¶: Gets expected-unbounded variables from a string

gpkit.tools.docstring.parse_variables(string, errorcatch=True)¶: Parses a string to determine what variables to create from it

gpkit.tools.docstring.variable_declaration(nameval, units, label, line, errorcatch=True)¶: Turns parsed output into a Variable declaration

gpkit.tools.docstring.vv_declare(string, flag, idx2, countstr)¶: Turns Variable declarations into VectorVariable ones

gpkit.tools.fmincon module¶

gpkit.tools.spdata module¶

gpkit.tools.tools module¶

Non-application-specific convenience methods for GPkit

gpkit.tools.tools.te_exp_minus1(posy, nterm)¶

Taylor expansion of e^{posy} - 1

posy : gpkit.Posynomial: Variable or expression to exponentiate
nterm : int: Number of non-constant terms in resulting Taylor expansion

gpkit.Posynomial: Taylor expansion of e^{posy} - 1, carried to nterm terms

gpkit.tools.tools.te_secant(var, nterm)¶

Taylor expansion of secant(var).

var : gpkit.monomial: Variable or expression argument
nterm : int: Number of non-constant terms in resulting Taylor expansion

gpkit.Posynomial: Taylor expansion of secant(x), carried to nterm terms

gpkit.tools.tools.te_tangent(var, nterm)¶

Taylor expansion of tangent(var).

var : gpkit.monomial: Variable or expression argument
nterm : int: Number of non-constant terms in resulting Taylor expansion

gpkit.Posynomial: Taylor expansion of tangent(x), carried to nterm terms

Module contents¶

Contains miscellaneous tools including fmincon comparison tool