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remove sol.sens

See original GitHub issue

I can’t figure out how to access a sensitivity…no matter what I try I get a key error. Here it is for one of the examples in the gpkit docs

In [20]: x = gpkit.Variable("x")

In [21]: x_min = gpkit.Variable("x_{min}", 2)

In [22]: sol = gpkit.Model(x, [x_min <= x]).solve()
Using solver 'cvxopt'
Solving for 1 variables.
Solving took 0.0114 seconds.

In [23]: assert sol.sens(x_min) == 1
---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-23-f25f4b83c012> in <module>()
----> 1 assert sol.sens(x_min) == 1

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/gpkit/solution_array.pyc in sens(self, key)
     76     def sens(self, key):
     77         "Returns sensitivity of the given variable (unitless)."
---> 78         return NomialArray(self["variables"]["sensitivities"][key])
     79 
     80     def table(self, tables=("cost", "sweepvariables", "freevariables",

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/gpkit/keydict.pyc in __getitem__(self, key)
     94         keys = self.keymap[key]
     95         if not keys:
---> 96             raise KeyError("%s was not found." % key)
     97         values = []
     98         for key in keys:

KeyError: 'sensitivities was not found.'

any help would be much appreciated…really need to access some sensitivies right now