fix cli arguments passed as unicode

Author: tomkralidis

.travis.yml

@@ -27,6 +27,7 @@ script:
   - python setup.py test
   - find . -type f -name "*.py" | xargs flake8
   - python setup.py --long-description | rst2html5.py
+  - pynumeric export -f pynumeric/tests/201611212330:PRECIPET,125,18,MPRATE_QPE,PRECIPET_QC_PARAMETERS_CMC:PRECIPET_NUMERIC_MMHR_WHK -o /tmp/test-output.tif -of GTiff
 
 after_success:
   - coverage run --source=pynumeric -m unittest pynumeric.tests.run_tests

pynumeric/__init__.py

@@ -165,8 +165,9 @@ def to_grid(self, filename='out.tif', fmt='GTiff'):
         maxy = ((self.metadata['LatCentre'] + resy * (height / 2)) -
                 (resy / 2))
 
-        dsource = gdal.GetDriverByName(fmt).Create(filename, width, height,
-                                                   1, gdal.GDT_Float64)
+        dsource = gdal.GetDriverByName(str(fmt)).Create(filename, width,
+                                                        height, 1,
+                                                        gdal.GDT_Float64)
 
         dsource.SetProjection(srs.ExportToWkt())