sdarray · astropenguin · Nov 16, 2021 · Nov 16, 2021 · Nov 16, 2021 · Nov 17, 2021
diff --git a/sdarray/__init__.py b/sdarray/__init__.py
@@ -3,5 +3,8 @@


 # submodules
-from . import coords
-from . import dims
+from . import array
+
+
+# aliases
+from .array import Array
diff --git a/sdarray/array/__init__.py b/sdarray/array/__init__.py
@@ -0,0 +1,9 @@
+# submodules
+from . import array
+from . import coords
+from . import dims
+from . import utils
+
+
+# aliases
+from .array import Array
diff --git a/sdarray/array/array.py b/sdarray/array/array.py
@@ -0,0 +1,85 @@
+# standard library
+from dataclasses import dataclass
+from typing import Any, Tuple
+
+
+# dependencies
+from xarray_dataclasses import AsDataArray, Coordof, Data
+
+
+# submodules
+from . import coords
+from . import dims
+from .utils import KeywordOnly
+
+
+# dataclasses
+@dataclass
+class Array(AsDataArray, KeywordOnly):
+    """Common single-dish data structure."""
+
+    data: Data[Tuple[dims.time, dims.chan], Any]
+    """Two-dimensional array data."""
+
+    mask: Coordof[coords.Mask] = False
+    """Mask of array data."""
+
+    sigma: Coordof[coords.Sigma] = 0.0
+    """Uncertainty of array data."""
+
+    weight: Coordof[coords.Weight] = 1.0
+    """Weight of array data."""
+
+    time: Coordof[dims.Time] = "2000-01-01"
+    """Start time in UTC."""
+
+    obs: Coordof[coords.Obs] = "0"
+    """Observation label."""
+
+    scan: Coordof[coords.Scan] = "0"
+    """Scan label."""
+
+    mode: Coordof[coords.Mode] = "0"
+    """Mode label."""
+
+    exposure: Coordof[coords.Exposure] = 0.0
+    """Exposure time."""
+
+    interval: Coordof[coords.Interval] = 0.0
+    """Interval time."""
+
+    longitude: Coordof[coords.Longitude] = 0.0
+    """Sky longitude."""
+
+    latitude: Coordof[coords.Latitude] = 0.0
+    """Sky latitude."""
+
+    chan: Coordof[dims.Chan] = 0
+    """Channel number."""
+
+    beam: Coordof[coords.Beam] = "0"
+    """Beam label."""
+
+    spw: Coordof[coords.SpW] = "0"
+    """Spectral window label."""
+
+    pol: Coordof[coords.Pol] = "0"
+    """Polarization label."""
+
+    lon_offset: Coordof[coords.LonOffset] = 0.0
+    """Offset from sky longitude."""
+
+    lat_offset: Coordof[coords.LatOffset] = 0.0
+    """Offset from sky latitude."""
+
+    center_freq: Coordof[coords.CenterFreq] = 0.0
+    """Center frequency."""
+
+    ref_freq: Coordof[coords.RefFreq] = 0.0
+    """Reference frequency."""
+
+    resolution: Coordof[coords.Resolution] = 0.0
+    """Spectral resolution."""
+
+    width: Coordof[coords.Width] = 0.0
+    """Channel width."""
diff --git a/sdarray/coords.py → sdarray/array/coords.py b/sdarray/coords.py → sdarray/array/coords.py
@@ -1,25 +1,3 @@
-__all__ = [
-    "Scan",
-    "Mode",
-    "Exposure",
-    "Interval",
-    "Longitude",
-    "Latitude",
-    "Beam",
-    "SpW",
-    "Pol",
-    "CenterFreq",
-    "RefFreq",
-    "Resolution",
-    "Width",
-    "LonOffset",
-    "LatOffset",
-    "Mask",
-    "Sigma",
-    "Weight",
-]
-
-
 # standard library
 from dataclasses import dataclass
 from typing import Tuple
@@ -31,15 +9,52 @@


 # submodules
-from .dims import time, chan
+from . import dims
+
+
+# dataclasses (time-chan data)
+@dataclass
+class Mask:
+    """Mask of array data."""
+
+    data: Data[Tuple[dims.time, dims.chan], np.bool_]
+    long_name: Attr[str] = "Mask for array data"
+    short_name: Attr[str] = "mask"
+
+
+@dataclass
+class Sigma:
+    """Uncertainty of array data."""
+
+    data: Data[Tuple[dims.time, dims.chan], np.float64]
+    long_name: Attr[str] = "Uncertainty of array data"
+    short_name: Attr[str] = "sigma"
+
+
+@dataclass
+class Weight:
+    """Weight of array data."""
+
+    data: Data[Tuple[dims.time, dims.chan], np.float64]
+    long_name: Attr[str] = "Weight for array data"
+    short_name: Attr[str] = "weight"


 # dataclasses (time labels)
+@dataclass
+class Obs:
+    """Observation label."""
+
+    data: Data[dims.time, np.str_]
+    long_name: Attr[str] = "Observation label"
+    short_name: Attr[str] = "obs"
+
+
 @dataclass
 class Scan:
    """Scan label."""

-    data: Data[time, np.str_]
+    data: Data[dims.time, np.str_]
    long_name: Attr[str] = "Scan label"
    short_name: Attr[str] = "scan"

@@ -48,17 +63,17 @@ class Scan:
 class Mode:
    """Mode label."""

-    data: Data[time, np.str_]
+    data: Data[dims.time, np.str_]
    long_name: Attr[str] = "Mode label"
    short_name: Attr[str] = "mode"


-# dataclasses (time observables)
+# dataclasses (time data)
 @dataclass
 class Exposure:
    """Exposure time."""

-    data: Data[time, np.float64]
+    data: Data[dims.time, np.float64]
    long_name: Attr[str] = "Exposure time"
    short_name: Attr[str] = "exposure"
    units: Attr[str] = "s"
@@ -68,7 +83,7 @@ class Exposure:
 class Interval:
    """Interval time."""

-    data: Data[time, np.float64]
+    data: Data[dims.time, np.float64]
    long_name: Attr[str] = "Interval time"
    short_name: Attr[str] = "interval"
    units: Attr[str] = "s"
@@ -78,7 +93,7 @@ class Interval:
 class Longitude:
    """Sky longitude."""

-    data: Data[time, np.float64]
+    data: Data[dims.time, np.float64]
    long_name: Attr[str] = "Sky longitude" ""
    short_name: Attr[str] = "longitude"
    units: Attr[str] = "deg"
@@ -88,7 +103,7 @@ class Longitude:
 class Latitude:
    """Sky latitude."""

-    data: Data[time, np.float64]
+    data: Data[dims.time, np.float64]
    long_name: Attr[str] = "Sky latitude"
    short_name: Attr[str] = "latitude"
    units: Attr[str] = "deg"
@@ -99,7 +114,7 @@ class Latitude:
 class Beam:
    """Beam label."""

-    data: Data[chan, np.str_]
+    data: Data[dims.chan, np.str_]
    long_name: Attr[str] = "Beam label"
    short_name: Attr[str] = "beam"

@@ -108,7 +123,7 @@ class Beam:
 class SpW:
    """Spectral window label."""

-    data: Data[chan, np.str_]
+    data: Data[dims.chan, np.str_]
    long_name: Attr[str] = "Spectral window label"
    short_name: Attr[str] = "spw"

@@ -117,17 +132,37 @@ class SpW:
 class Pol:
    """Polarization label."""

-    data: Data[chan, np.str_]
+    data: Data[dims.chan, np.str_]
    long_name: Attr[str] = "Polarization label"
    short_name: Attr[str] = "pol"


-# dataclasses (chan observables)
+# dataclasses (chan data)
+@dataclass
+class LonOffset:
+    """Offset from sky longitude."""
+
+    data: Data[dims.chan, np.float64]
+    long_name: Attr[str] = "Offset from sky longitude"
+    short_name: Attr[str] = "lon_offset"
+    units: Attr[str] = "deg"
+
+
+@dataclass
+class LatOffset:
+    """Offset from sky latitude."""
+
+    data: Data[dims.chan, np.float64]
+    long_name: Attr[str] = "Offset from sky latitude"
+    short_name: Attr[str] = "lat_offset"
+    units: Attr[str] = "deg"
+
+
 @dataclass
 class CenterFreq:
    """Center frequency."""

-    data: Data[chan, np.float64]
+    data: Data[dims.chan, np.float64]
    long_name: Attr[str] = "Center frequency"
    short_name: Attr[str] = "center_freq"
    units: Attr[str] = "Hz"
@@ -137,7 +172,7 @@ class CenterFreq:
 class RefFreq:
    """Reference frequency."""

-    data: Data[chan, np.float64]
+    data: Data[dims.chan, np.float64]
    long_name: Attr[str] = "Reference frequency"
    short_name: Attr[str] = "ref_freq"
    units: Attr[str] = "Hz"
@@ -147,7 +182,7 @@ class RefFreq:
 class Resolution:
    """Spectral resolution."""

-    data: Data[chan, np.float64]
+    data: Data[dims.chan, np.float64]
    long_name: Attr[str] = "Spectral resolution"
    short_name: Attr[str] = "resolution"
    units: Attr[str] = "Hz"
@@ -157,55 +192,7 @@ class Resolution:
 class Width:
    """Channel width."""

-    data: Data[chan, np.float64]
+    data: Data[dims.chan, np.float64]
    long_name: Attr[str] = "Channel width"
    short_name: Attr[str] = "width"
    units: Attr[str] = "Hz"
-
-
-@dataclass
-class LonOffset:
-    """Offset from sky longitude."""
-
-    data: Data[chan, np.float64]
-    long_name: Attr[str] = "Offset from sky longitude"
-    short_name: Attr[str] = "lon_offset"
-    units: Attr[str] = "deg"
-
-
-@dataclass
-class LatOffset:
-    """Offset from sky latitude."""
-
-    data: Data[chan, np.float64]
-    long_name: Attr[str] = "Offset from sky latitude"
-    short_name: Attr[str] = "lat_offset"
-    units: Attr[str] = "deg"
-
-
-# dataclasses (time-chan observables)
-@dataclass
-class Mask:
-    """Mask for an array."""
-
-    data: Data[Tuple[time, chan], np.bool_]
-    long_name: Attr[str] = "Mask for an array"
-    short_name: Attr[str] = "mask"
-
-
-@dataclass
-class Sigma:
-    """Uncertainty of an array."""
-
-    data: Data[Tuple[time, chan], np.float64]
-    long_name: Attr[str] = "Uncertainty of an array"
-    short_name: Attr[str] = "sigma"
-
-
-@dataclass
-class Weight:
-    """Weight for an array."""
-
-    data: Data[Tuple[time, chan], np.float64]
-    long_name: Attr[str] = "Weight for an array"
-    short_name: Attr[str] = "weight"