always allow trying mosek_cli (#966)

* closes #963
* allow gpkit_build to be run from another directory
* don't assume a mosek_bin_dir was found

gpkit/_mosek/cli_expopt.py

@@ -35,8 +35,9 @@ def imize_fn(path=None, clearfiles=True):
     if not path:
         path = tempfile.mkdtemp()
     filename = path + os.sep + "gpkit_mosek"
-    os.environ['PATH'] = (os.environ['PATH'] + ':%s' %
-                          settings["mosek_bin_dir"])
+    if "mosek_bin_dir" in settings:
+        os.environ['PATH'] = ":".join([os.environ['PATH'],
+                                       settings["mosek_bin_dir"]])
 
     # pylint: disable=unused-argument
     def imize(c, A, p_idxs, *args, **kwargs):

gpkit/build.py

@@ -6,7 +6,6 @@
 import shutil
 import subprocess
 import glob
-import platform
 
 LOGSTR = ""
 settings = {}
@@ -100,13 +99,6 @@ class MosekCLI(SolverBackend):
 
     def look(self):
         "Attempts to run mskexpopt."
-
-        if sys.platform == "win32":
-            ## does not work on 32-bit windows ##
-            log("# Build script does not support mosek_cli"
-                " your architecture (%s)" % platform.architecture()[0])
-            return
-
         try:
             log("#   Trying to run mskexpopt...")
             if call("mskexpopt") in (1052, 28):  # 28 for MacOSX
@@ -121,7 +113,7 @@ class CVXopt(SolverBackend):
     name = "cvxopt"
 
     def look(self):
-        "Attempts to import mskexpopt."
+        "Attempts to import cvxopt."
         try:
             log("#   Trying to import cvxopt...")
             # Testing the import, so the variable is intentionally not used
@@ -279,7 +271,12 @@ def build(self):
 
 def build_gpkit():
     "Builds GPkit"
-    global settings  # pylint: disable=global-variable-not-assigned
+    try:
+        import gpkit
+        log("# Moving to the directory from which GPkit was imported.")
+        os.chdir(gpkit.__path__[0])
+    except ImportError:
+        pass
 
     if isfile("__init__.py"):
         #call("ls")

gpkit/nomials/array.py

@@ -59,7 +59,7 @@ class NomialArray(np.ndarray):
     __repr__ = _repr
     _repr_latex_ = _repr_latex_
 
-    def str_without(self, excluded=()):
+    def str_without(self, excluded=None):
         "Returns string without certain fields (such as 'models')."
         if self.shape:
             return "[" + ", ".join([try_str_without(el, excluded)