xarray.concat¶
-
xarray.
concat
(objs, dim, data_vars='all', coords='different', compat='equals', positions=None, fill_value=<NA>, join='outer')¶ Concatenate xarray objects along a new or existing dimension.
- Parameters
objs (sequence of Dataset and DataArray objects) – xarray objects to concatenate together. Each object is expected to consist of variables and coordinates with matching shapes except for along the concatenated dimension.
dim (str or DataArray or pandas.Index) – Name of the dimension to concatenate along. This can either be a new dimension name, in which case it is added along axis=0, or an existing dimension name, in which case the location of the dimension is unchanged. If dimension is provided as a DataArray or Index, its name is used as the dimension to concatenate along and the values are added as a coordinate.
data_vars ({'minimal', 'different', 'all' or list of str}, optional) –
- These data variables will be concatenated together:
’minimal’: Only data variables in which the dimension already appears are included.
’different’: Data variables which are not equal (ignoring attributes) across all datasets are also concatenated (as well as all for which dimension already appears). Beware: this option may load the data payload of data variables into memory if they are not already loaded.
’all’: All data variables will be concatenated.
list of str: The listed data variables will be concatenated, in addition to the ‘minimal’ data variables.
If objects are DataArrays, data_vars must be ‘all’.
coords ({'minimal', 'different', 'all' or list of str}, optional) –
- These coordinate variables will be concatenated together:
’minimal’: Only coordinates in which the dimension already appears are included.
’different’: Coordinates which are not equal (ignoring attributes) across all datasets are also concatenated (as well as all for which dimension already appears). Beware: this option may load the data payload of coordinate variables into memory if they are not already loaded.
’all’: All coordinate variables will be concatenated, except those corresponding to other dimensions.
list of str: The listed coordinate variables will be concatenated, in addition to the ‘minimal’ coordinates.
compat ({'identical', 'equals', 'broadcast_equals', 'no_conflicts', 'override'}, optional) –
String indicating how to compare non-concatenated variables of the same name for potential conflicts. This is passed down to merge.
’broadcast_equals’: all values must be equal when variables are broadcast against each other to ensure common dimensions.
’equals’: all values and dimensions must be the same.
’identical’: all values, dimensions and attributes must be the same.
’no_conflicts’: only values which are not null in both datasets must be equal. The returned dataset then contains the combination of all non-null values.
’override’: skip comparing and pick variable from first dataset
positions (None or list of integer arrays, optional) – List of integer arrays which specifies the integer positions to which to assign each dataset along the concatenated dimension. If not supplied, objects are concatenated in the provided order.
fill_value (scalar, optional) – Value to use for newly missing values
join ({'outer', 'inner', 'left', 'right', 'exact'}, optional) –
String indicating how to combine differing indexes (excluding dim) in objects
’outer’: use the union of object indexes
’inner’: use the intersection of object indexes
’left’: use indexes from the first object with each dimension
’right’: use indexes from the last object with each dimension
’exact’: instead of aligning, raise ValueError when indexes to be aligned are not equal
’override’: if indexes are of same size, rewrite indexes to be those of the first object with that dimension. Indexes for the same dimension must have the same size in all objects.
- Returns
concatenated
- Return type
type of objs
Notes
Each concatenated Variable preserves corresponding
attrs
from the first element ofobjs
.See also