can't convert a pd.DataFrame with all empty string to ctable

[rabbit8ge]

like:

bcolz.ctable.fromdataframe(pd.DataFrame({'a':[1,2,3],'b':['','','']})) D:\Anaconda2\lib\site-packages\bcolz\ctable.py:693: FutureWarning: pandas.lib is deprecated and will be removed in a future version. You can access infer_dtype as pandas.api.types.infer_dtype inferred_type = pd.lib.infer_dtype(vals) Traceback (most recent call last): File "", line 1, in File "D:\Anaconda2\lib\site-packages\bcolz\ctable.py", line 703, in fromdataframe (dtype, maxitemsize), **ckwargs) File "bcolz/carray_ext.pyx", line 1063, in bcolz.carray_ext.carray.cinit (bcolz\carray_ext.c:14817) File "bcolz/carray_ext.pyx", line 1146, in bcolz.carray_ext.carray._create_carray (bcolz\carray_ext.c:15653) File "bcolz/carray_ext.pyx", line 1094, in bcolz.carray_ext.carray._adapt_dtype (bcolz\carray_ext.c:15193) ValueError: invalid itemsize in generic type tuple