predef

variable protection

Calling Sequence

n = predef()
oldnew = predef(n)
oldnew = predef('all')
oldnew = predef('clear')
variables_name = predef('names')

Description

Utility function used for defining “oldest” variables as “protected”. Protected variables cannot be killed. They are not saved by the ‘save’ command. The “oldest” are those appearing last in the who(‘get’).

predef() gets the number of protected variables.

predef(‘a[ll]’) sets all the variables protected, it also return the old and new value of protected variables number.

predef(‘c[lear]’) unprotect all but the last 7 variables, it also return the old and new value of protected variables number.

predef(n) sets the max(n,7) last defined variables as protected, it also return the old and new value of protected variables number.

predef(‘names’) returns a vector of strings with the name of protected variables.

Remarks

Variable ans created automatically when expressions are not assigned is never protected by predef(‘all’).

A number of protected variables are set in the start-up file SCI/etc/scilab.start. User may in particular set its own predefined variables in user’s startup files SCIHOME/.scilab and SCIHOME/scilab.ini

See Also

• clear kills variables
• save Save a variable or a serie of variables in a binary file
• ans answer
• startup startup files