def as_json_table_type(x):
"""
Convert a NumPy / pandas type to its corresponding json_table.
Parameters
----------
x : array or dtype
Returns
-------
t : str
the Table Schema data types
Notes
-----
This table shows the relationship between NumPy / pandas dtypes,
and Table Schema dtypes.
============== =================
Pandas type Table Schema type
============== =================
int64 integer
float64 number
bool boolean
datetime64[ns] datetime
timedelta64[ns] duration
object str
categorical any
=============== =================
"""
if is_integer_dtype(x):
return 'integer'
elif is_bool_dtype(x):
return 'boolean'
elif is_numeric_dtype(x):
return 'number'
elif (is_datetime64_dtype(x) or is_datetime64tz_dtype(x) or
is_period_dtype(x)):
return 'datetime'
elif is_timedelta64_dtype(x):
return 'duration'
elif is_categorical_dtype(x):
return 'any'
elif is_string_dtype(x):
return 'string'
else:
return 'any'
def as_json_table_type(x):
"""
Convert a NumPy / pandas type to its corresponding json_table.
Parameters
----------
x : array or dtype
Returns
-------
t : str
the Table Schema data types
Notes
-----
This table shows the relationship between NumPy / pandas dtypes,
and Table Schema dtypes.
============== =================
Pandas type Table Schema type
============== =================
int64 integer
float64 number
bool boolean
datetime64[ns] datetime
timedelta64[ns] duration
object str
categorical any
=============== =================
"""
if is_integer_dtype(x):
return 'integer'
elif is_bool_dtype(x):
return 'boolean'
elif is_numeric_dtype(x):
return 'number'
elif (is_datetime64_dtype(x) or is_datetime64tz_dtype(x)
or is_period_dtype(x)):
return 'datetime'
elif is_timedelta64_dtype(x):
return 'duration'
elif is_categorical_dtype(x):
return 'any'
elif is_string_dtype(x):
return 'string'
else:
return 'any'
def make_sparse(arr, kind='block', fill_value=None):
"""
Convert ndarray to sparse format
Parameters
----------
arr : ndarray
kind : {'block', 'integer'}
fill_value : NaN or another value
Returns
-------
(sparse_values, index) : (ndarray, SparseIndex)
"""
arr = _sanitize_values(arr)
if arr.ndim > 1:
raise TypeError("expected dimension <= 1 data")
if fill_value is None:
fill_value = na_value_for_dtype(arr.dtype)
if isnull(fill_value):
mask = notnull(arr)
else:
# For str arrays in NumPy 1.12.0, operator!= below isn't
# element-wise but just returns False if fill_value is not str,
# so cast to object comparison to be safe
if is_string_dtype(arr):
arr = arr.astype(object)
mask = arr != fill_value
length = len(arr)
if length != mask.size:
# the arr is a SparseArray
indices = mask.sp_index.indices
else:
indices = mask.nonzero()[0].astype(np.int32)
index = _make_index(length, indices, kind)
sparsified_values = arr[mask]
return sparsified_values, index, fill_value
def make_sparse(arr, kind='block', fill_value=None):
"""
Convert ndarray to sparse format
Parameters
----------
arr : ndarray
kind : {'block', 'integer'}
fill_value : NaN or another value
Returns
-------
(sparse_values, index) : (ndarray, SparseIndex)
"""
arr = _sanitize_values(arr)
if arr.ndim > 1:
raise TypeError("expected dimension <= 1 data")
if fill_value is None:
fill_value = na_value_for_dtype(arr.dtype)
if isnull(fill_value):
mask = notnull(arr)
else:
# For str arrays in NumPy 1.12.0, operator!= below isn't
# element-wise but just returns False if fill_value is not str,
# so cast to object comparison to be safe
if is_string_dtype(arr):
arr = arr.astype(object)
mask = arr != fill_value
length = len(arr)
if length != mask.size:
# the arr is a SparseArray
indices = mask.sp_index.indices
else:
indices = mask.nonzero()[0].astype(np.int32)
index = _make_index(length, indices, kind)
sparsified_values = arr[mask]
return sparsified_values, index, fill_value
def test_not_string(self):
# though PeriodDtype has object kind, it cannot be string
self.assertFalse(is_string_dtype(PeriodDtype('D')))
def test_not_string(self):
# though PeriodDtype has object kind, it cannot be string
self.assertFalse(is_string_dtype(PeriodDtype('D')))
