open
- asdf.open(fd, uri=None, mode=None, validate_checksums=False, extensions=None, ignore_version_mismatch=True, ignore_unrecognized_tag=False, _force_raw_types=False, copy_arrays=False, memmap=NotSet, lazy_tree=NotSet, lazy_load=True, custom_schema=None, strict_extension_check=False, ignore_missing_extensions=False, _get_yaml_content=False)
Open an existing ASDF file.
- Parameters:
- fdstring or file-like object
May be a string
file
orhttp
URI, or a Python file-like object.- uristring, optional
The URI of the file. Only required if the URI can not be automatically determined from
fd
.- modestring, optional
The mode to open the file in. Must be
r
(default) orrw
.- validate_checksumsbool, optional
If
True
, validate the blocks against their checksums. Requires reading the entire file, so disabled by default.- extensionsobject, optional
Additional extensions to use when reading and writing the file. May be an
asdf.extension.Extension
or alist
of extensions.- ignore_version_mismatchbool, optional
When
True
, do not raise warnings for mismatched schema versions. Set toTrue
by default.- ignore_unrecognized_tagbool, optional
When
True
, do not raise warnings for unrecognized tags. Set toFalse
by default.- copy_arraysbool, optional
When
False
, when reading files, attempt to memmap underlying data arrays when possible.- memmapbool, optional
When
True
, when reading files, attempt to memmap underlying data arrays when possible. When set, this argument will overridecopy_arrays
. When not set, thecopy_arrays
will determine if arrays are memory mapped or copied.copy_arrays
will be deprecated and the default will change in an upcoming asdf version which by default will not memory map arrays.- lazy_loadbool, optional
When
True
and the underlying file handle is seekable, data arrays will only be loaded lazily: i.e. when they are accessed for the first time. In this case the underlying file must stay open during the lifetime of the tree. Setting to False causes all data arrays to be loaded up front, which means that they can be accessed even after the underlying file is closed. Note: even iflazy_load
isFalse
,memmap
is still taken into account.- lazy_treebool, optional
When
True
the ASDF tree will not be converted to custom objects when the file is loaded. Instead, objects will be “lazily” converted only when they are accessed. Note that the tree will not contain dict and list instances for containers and instead return instances of classes defined inasdf.lazy_nodes
. Since objects are converted when they are accessed, traversing the tree (like is done duringAsdfFile.info
andAsdfFile.search
) will result in nodes being converted.- custom_schemastr, optional
Path to a custom schema file that will be used for a secondary validation pass. This can be used to ensure that particular ASDF files follow custom conventions beyond those enforced by the standard.
- strict_extension_checkbool, optional
When
True
, if the given ASDF file contains metadata about the extensions used to create it, and if those extensions are not installed, opening the file will fail. WhenFalse
, opening a file under such conditions will cause only a warning. Defaults toFalse
.- ignore_missing_extensionsbool, optional
When
True
, do not raise warnings when a file is read that contains metadata about extensions that are not available. Defaults toFalse
.
- Returns:
- asdffileAsdfFile
The new AsdfFile object.