MATLAB Programming

Accessing Files with Memory-Mapping
Data: 4872x1 double array
You can also change the value of any property after the object has been
constructed. Use the syntax
objname.property = newvalue;
Forexample,tosettheformattouint16, type the following. (Property names,
like Format, arenotcasesensitive.)
m.format = 'uint16'
m =
Filename: 'd:\matlab\mfiles\records.dat'
Writable: true
Offset: 1024
Format: 'uint16'
Repeat: Inf
Data: 19488x1 uint16 array
Further read and write operations to the region mapped by m will now treat
the data in the file as a sequence of unsigned 16-bit integers. Whenever you
change the value of a memmapfile property, MATLAB remaps the file to
memory.
Selecting the File to Map
filename is the only required argument when you call the memmapfile
constructor. When you call the memmapfile constructor, MATLAB assigns the
filename that you specify to the Filename property of the new object instance.
Specify the filename as a quoted string, (e.g., 'records.dat'). It must be first
in the argument list and not specified as a parameter-value pair. filename
must include a filename extension if the name of the file being mapped has an
extension. The filename argument cannot include any wildcard characters
(e.g., * or ?), and is not case sensitive.
Note Unlike the other memmapfile constructor arguments, you must specify
filename as a single string, and not as a parameter-value pair.
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