Typo fixes in io_gpf.py (#22)

* Typo fixes in io_gpf.py. Column labels now match case of headers in Socet Set spec for GPF files.

* More typo fixes for GPF column labels in IO script and test data

plio/examples/SocetGXP/InSightE08_XW.csv

-point_id,stat,known,lat_y_North,long_X_East,ht,sigma0,sigma1,sigma2,res0,res1,res2
+point_id,stat,known,lat_Y_North,long_X_East,ht,sigma0,sigma1,sigma2,res0,res1,res2
 1,1,1,0.08538133869186999,2.38013146162178,-2697.2374469465,0.0,0.0,1.707214,16.348041000000002,-13.917623,-0.151001
 2,1,1,0.08508542650082002,2.3808135855714703,-2702.0,0.0,0.0,1.0,15.983285999999998,-16.869508,0.103341
 3,1,1,0.08626480095809,2.3870838392611,-2714.16003756809,0.0,0.0,3.828854,12.831839,-34.360639,-2.2058459999999998

plio/io/io_gpf.py

@@ -13,7 +13,7 @@ def read_gpf(input_data):
     Returns
     -------
     df : pd.DataFrame
-         containing the gfp data with appropriate column names and indices
+         containing the gpf data with appropriate column names and indices
     """
 
     # Check that the number of rows is matching the expected number
@@ -32,7 +32,7 @@ def read_gpf(input_data):
     #TODO: cols should be used to dynamically generate the column names
 
     df = pd.DataFrame(d, columns=['point_id', 'stat', 'known',
-                              'lat_y_North', 'long_X_East','ht',
+                              'lat_Y_North', 'long_X_East','ht',
                               'sigma0', 'sigma1', 'sigma2',
                               'res0', 'res1', 'res2'])
 
@@ -80,7 +80,7 @@ def save_gpf(df, output_file):
     for index,row in df.iterrows():
         #Output coordinates to gpf file
         outGPF.write('{0} {1} {2}\n'.format(row['point_id'], row['stat'], row['known']))
-        outGPF.write('{0}         {1}         {2}\n'.format(row['lat_y_North'], row['long_X_East'], row['ht']))
+        outGPF.write('{0}         {1}         {2}\n'.format(row['lat_Y_North'], row['long_X_East'], row['ht']))
         outGPF.write('{0} {1} {2}\n'.format(row['sigma0'], row['sigma1'], row['sigma2']))
         outGPF.write('{0} {1} {2}\n\n'.format(row['res0'], row['res1'], row['res2']))