lib.format.open_memmap(filename, mode='r+', dtype=None, shape=None, fortran_order=False, version=None, *, max_header_size=10000)
Open a .npy file as a memory-mapped array.
This may be used to read an existing file or create a new one.
Parameters:filenamestr or path-likeThe name of the file on disk. This may not be a file-like object.
modestr, optionalThe mode in which to open the file; the default is ‘r+’. In addition to the standard file modes, ‘c’ is also accepted to mean “copy on write.” See
for the available mode strings.
dtypedata-type, optionalThe data type of the array if we are creating a new file in “write” mode, if not,
is ignored. The default value is None, which results in a data-type of
.
shapetuple of intThe shape of the array if we are creating a new file in “write” mode, in which case this parameter is required. Otherwise, this parameter is ignored and is thus optional.
fortran_orderbool, optionalWhether the array should be Fortran-contiguous (True) or C-contiguous (False, the default) if we are creating a new file in “write” mode.
versiontuple of int (major, minor) or NoneIf the mode is a “write” mode, then this is the version of the file format used to create the file. None means use the oldest supported version that is able to store the data. Default: None
max_header_sizeint, optionalMaximum allowed size of the header. Large headers may not be safe to load securely and thus require explicitly passing a larger value. See
for details.
Returns:marraymemmapThe memory-mapped array.
Raises:ValueErrorIf the data or the mode is invalid.
OSErrorIf the file is not found or cannot be opened correctly.