Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

FIX: do not cast _FillValue/missing_value in CFMaskCoder if _Unsigned is provided #8852

Merged
merged 3 commits into from
Mar 19, 2024
Merged

FIX: do not cast _FillValue/missing_value in CFMaskCoder if _Unsigned is provided #8852

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
61a24f2
FIX: do not cast _FillValue/missing_value in CFMaskCoder if _Unsigned…
kmuehlbauer Mar 19, 2024
b0a7f2b
add whats-new.rst entry
kmuehlbauer Mar 19, 2024
82463fe
add comment on _Unsigned
kmuehlbauer Mar 19, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 3 additions & 0 deletions doc/whats-new.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -57,6 +57,9 @@ Bug fixes
`CFMaskCoder`/`CFScaleOffsetCoder` (:issue:`2304`, :issue:`5597`,
:issue:`7691`, :pull:`8713`, see also discussion in :pull:`7654`).
By `Kai Mühlbauer <https://github.com/kmuehlbauer>`_.
- do not cast `_FillValue`/`missing_value` in `CFMaskCoder` if `_Unsigned` is provided
(:issue:`8844`, :pull:`8852`).
By `Kai Mühlbauer <https://github.com/kmuehlbauer>`_.

Documentation
~~~~~~~~~~~~~
Expand Down
14 changes: 11 additions & 3 deletions xarray/coding/variables.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -309,6 +309,9 @@ def encode(self, variable: Variable, name: T_Name = None):
dtype = np.dtype(encoding.get("dtype", data.dtype))
fv = encoding.get("_FillValue")
mv = encoding.get("missing_value")
# to properly handle _FillValue/missing_value below [a], [b]
# we need to check if unsigned data is written as signed data
unsigned = encoding.get("_Unsigned") is not None
kmuehlbauer marked this conversation as resolved.
Show resolved Hide resolved

fv_exists = fv is not None
mv_exists = mv is not None
Expand All @@ -323,13 +326,19 @@ def encode(self, variable: Variable, name: T_Name = None):

if fv_exists:
# Ensure _FillValue is cast to same dtype as data's
encoding["_FillValue"] = dtype.type(fv)
# [a] need to skip this if _Unsigned is available
if not unsigned:
encoding["_FillValue"] = dtype.type(fv)
fill_value = pop_to(encoding, attrs, "_FillValue", name=name)

if mv_exists:
# try to use _FillValue, if it exists to align both values
# or use missing_value and ensure it's cast to same dtype as data's
encoding["missing_value"] = attrs.get("_FillValue", dtype.type(mv))
# [b] need to provide mv verbatim if _Unsigned is available
encoding["missing_value"] = attrs.get(
"_FillValue",
(dtype.type(mv) if not unsigned else mv),
)
fill_value = pop_to(encoding, attrs, "missing_value", name=name)

# apply fillna
Expand Down Expand Up @@ -522,7 +531,6 @@ def encode(self, variable: Variable, name: T_Name = None) -> Variable:
def decode(self, variable: Variable, name: T_Name = None) -> Variable:
if "_Unsigned" in variable.attrs:
dims, data, attrs, encoding = unpack_for_decoding(variable)

unsigned = pop_to(attrs, encoding, "_Unsigned")

if data.dtype.kind == "i":
Expand Down
Loading