matlab學習之persistent變數的使用
阿新 • • 發佈：2019-01-08
persistent Define persistent variable.
persistent X Y Z defines X, Y, and Z as variables that are local
to the function in which they are declared yet their values are
retained in memory between calls to the function. Persistent
variables are similar to global variables because MATLAB creates
permanent storage for both. They differ from global variables in
that persistent variables are known only to the function in which
they are declared. This prevents persistent variables from being
changed by other functions or from the MATLAB command line.
Persistent variables are cleared when the M-file is cleared from
memory or when the M-file is changed. To keep an M-file in memory
until MATLAB quits, use MLOCK.
If the persistent variable does not exist the first time you issue
the persistent statement, it will be initialized to the empty matrix.
It is an error to declare a variable persistent if a variable with
the same name exists in the current workspace.
persistent X Y Z defines X, Y, and Z as variables that are local
to the function in which they are declared yet their values are
retained in memory between calls to the function. Persistent
variables are similar to global variables because MATLAB creates
permanent storage for both. They differ from global variables in
that persistent variables are known only to the function in which
they are declared. This prevents persistent variables from being
changed by other functions or from the MATLAB command line.
Persistent variables are cleared when the M-file is cleared from
memory or when the M-file is changed. To keep an M-file in memory
until MATLAB quits, use MLOCK.
If the persistent variable does not exist the first time you issue
the persistent statement, it will be initialized to the empty matrix.
It is an error to declare a variable persistent if a variable with
the same name exists in the current workspace.