working parse var for py3, just needs line numbers

docs/source/examples/performance_modeling.py

@@ -1,7 +1,7 @@
 """Modular aircraft concept"""
 import pickle
 import numpy as np
-from gpkit import Model, Vectorize, parse_variables
+from gpkit import Model, Vectorize, parse_variables, pv_decorater
 
 
 class AircraftP(Model):
@@ -21,10 +21,10 @@ class AircraftP(Model):
     Wfuel, aircraft.W, state.mu
 
     """
+    @pv_decorater(__doc__, globals())
     def setup(self, aircraft, state):
         self.aircraft = aircraft
         self.state = state
-        exec(parse_variables(AircraftP.__doc__))
 
         self.wing_aero = aircraft.wing.dynamic(aircraft.wing, state)
         self.perf_models = [self.wing_aero]
@@ -62,8 +62,8 @@ class Aircraft(Model):
     ---------------
     wing.c, wing.S
     """
+    @pv_decorater(__doc__, globals())
     def setup(self):
-        exec(parse_variables(Aircraft.__doc__))
         self.fuse = Fuselage()
         self.wing = Wing()
         self.components = [self.fuse, self.wing]
@@ -87,8 +87,9 @@ class FlightState(Model):
     rho   0.74     [kg/m^3]   air density
 
     """
+    @pv_decorater(__doc__, globals())
     def setup(self):
-        exec(parse_variables(FlightState.__doc__))
+        pass
 
 
 class FlightSegment(Model):
@@ -103,6 +104,7 @@ class FlightSegment(Model):
     Wfuel, aircraft.W
 
     """
+    @pv_decorater(__doc__, globals())
     def setup(self, aircraft):
         self.aircraft = aircraft
 
@@ -165,10 +167,11 @@ class WingAero(Model):
     ---------------
     CL, wing.S, state.mu, state.rho, state.V
     """
+    @pv_decorater(__doc__, globals())
     def setup(self, wing, state):
         self.wing = wing
         self.state = state
-        exec(parse_variables(WingAero.__doc__))
+        assert False
 
         c = wing.c
         A = wing.A
@@ -205,8 +208,8 @@ class Wing(Model):
     ---------------
     c, S
     """
+    @pv_decorater(__doc__, globals())
     def setup(self):
-        exec(parse_variables(Wing.__doc__))
         return {"parametrization of wing weight":
                     W >= S*rho,
                 "definition of mean chord":
@@ -225,32 +228,33 @@ class Fuselage(Model):
     W  100 [lbf]  weight
 
     """
+    @pv_decorater(__doc__, globals())
     def setup(self):
-        exec(parse_variables(Fuselage.__doc__))
+        pass
 
 AC = Aircraft()
 MISSION = Mission(AC)
 M = Model(MISSION.takeoff_fuel, [MISSION, AC])
 print(M)
 sol = M.solve(verbosity=0)
-# save solution to some files
-sol.savemat()
-sol.savecsv()
-sol.savetxt()
-sol.save("solution.pkl")
-# retrieve solution from a file
-sol_loaded = pickle.load(open("solution.pkl"))
-
-vars_of_interest = set(AC.varkeys)
-# note that there's two ways to access submodels
-assert (MISSION["flight segment"]["aircraft performance"]
-        is MISSION.fs.aircraftp)
-vars_of_interest.update(MISSION.fs.aircraftp.unique_varkeys)
-vars_of_interest.add(M["D"])
-print(sol.summary(vars_of_interest))
-print(sol.table(tables=["loose constraints"]))
-
-MISSION["flight segment"]["aircraft performance"]["fuel burn rate"] = (
-    MISSION.fs.aircraftp.Wburn >= 0.2*MISSION.fs.aircraftp.wing_aero.D)
-sol = M.solve(verbosity=0)
-print(sol.diff("solution.pkl", showvars=vars_of_interest, sortbymodel=False))
+# # save solution to some files
+# sol.savemat()
+# sol.savecsv()
+# sol.savetxt()
+# sol.save("solution.pkl")
+# # retrieve solution from a file
+# sol_loaded = pickle.load(open("solution.pkl"))
+#
+# vars_of_interest = set(AC.varkeys)
+# # note that there's two ways to access submodels
+# assert (MISSION["flight segment"]["aircraft performance"]
+#         is MISSION.fs.aircraftp)
+# vars_of_interest.update(MISSION.fs.aircraftp.unique_varkeys)
+# vars_of_interest.add(M["D"])
+# print(sol.summary(vars_of_interest))
+# print(sol.table(tables=["loose constraints"]))
+#
+# MISSION["flight segment"]["aircraft performance"]["fuel burn rate"] = (
+#     MISSION.fs.aircraftp.Wburn >= 0.2*MISSION.fs.aircraftp.wing_aero.D)
+# sol = M.solve(verbosity=0)
+# print(sol.diff("solution.pkl", showvars=vars_of_interest, sortbymodel=False))

docs/source/examples/pm_test.py

@@ -0,0 +1,3 @@
+from performance_modeling import Wing
+
+print(Wing())

gpkit/__init__.py

@@ -17,6 +17,41 @@
 from .constraints.model import Model
 from .tools.docstring import parse_variables
 
+import inspect
+import ast
+
+
+class pv_decorater(object):
+
+    def __init__(self, string, globals):
+        self.string = string
+        self.globals = globals
+
+    def __call__(self, f):
+        string = self.string
+        orig_source = inspect.getsource(f)
+        # print("os\n", orig_source)
+        orig_lines = orig_source.split("\n")
+        indent_length = 0
+        while orig_lines[1][indent_length] in [" ", "\t"]:
+            indent_length += 1
+        first_indent_length = indent_length
+        while orig_lines[2][indent_length] in [" ", "\t"]:
+            indent_length += 1
+        second_indent = orig_lines[2][:indent_length]
+        parse_lines = [second_indent + line for line in parse_variables(string).split("\n")]
+        # make ast of these new lines, insert it into the original ast
+        new_lines = [orig_lines[1]] + parse_lines + orig_lines[2:]
+        new_src = "\n".join([line[first_indent_length:] for line in new_lines])
+        # print("ns\n%s" % new_src)
+        new_ast = ast.parse(new_src, "<parse_variables>")
+        ast.fix_missing_locations(new_ast)
+        code = compile(new_ast, "<parse_variables>", "exec", dont_inherit=True)
+        out = {}
+        exec(code, self.globals, out)
+        return out[f.__name__]
+
+
 GPBLU = "#59ade4"
 GPCOLORS = ["#59ade4", "#FA3333"]
 

gpkit/constraints/set.py

@@ -262,6 +262,8 @@ def process_result(self, result):
 
     def __repr__(self):
         "Returns namespaced string."
+        if not self:
+            return "<gpkit.%s object>" % self.__class__.__name__
         return ("<gpkit.%s object containing %i top-level constraint(s)"
                 " and %i variable(s)>" % (self.__class__.__name__,
                                           len(self), len(self.varkeys)))

gpkit/tools/docstring.py

@@ -1,6 +1,5 @@
 "Docstring-parsing methods"
 import re
-import sys
 import numpy as np
 
 
@@ -59,8 +58,6 @@ def expected_unbounded(instance, doc):
 
 def parse_variables(string, errorcatch=True):
     "Parses a string to determine what variables to create from it"
-    if sys.version_info >= (3, 0):
-        raise FutureWarning("parse_variables is not yet supported in Python 3")
     out = "from gpkit import Variable, VectorVariable\n"
     out += check_and_parse_flag(string, "Constants\n", errorcatch,
                                 constant_declare)

test.py

@@ -0,0 +1,15 @@
+from gpkit import *
+from gpkit.nomials.array import NomialArray
+import numpy as np
+
+t = Variable("t")
+u = Variable("u")
+v = Variable("v")
+w = Variable("w")
+x = VectorVariable(3, "x")
+y = VectorVariable(3, "y")
+z = VectorVariable(3, "z")
+a = VectorVariable((3, 2), "a")
+b = VectorVariable((3, 2), "b")
+
+print w >= x