System Functions and Variables

[]CR Display Function

Given a function name as right parameter, []CR returns the source code of the function in a character matrix. The extra space in a line will be filled with blanks.

[]CR 'function name' //two quotes are required

[]open and []close

h<-[]open v Open a file and start file stream
t<-[]close h Close file stream with specified file handler
v String, presents the path of the designated file
h File handler with integer value greater equal than 1000

Usually, []open and []close are used in pairs. []open opens a file and saves a handler for file streaming and []close safely closes the file stream at the end of writing. []open allows multiple file open on a same file, but a different file handler will be returned. []close checks the file handler before it is closed. If it is a valid one, it will be closed immediately with return value 0. Otherwise, an integer 1 should be returned.

[]PP Printing Precision

[]PP<-V Set the precision of printing for floating point and complex number
V Positive integer scalar
Default value 10

[]PP is a system variable and its value should be greater than 0. On the other words, the minimal value of []PP is 1. []PP controls the output precision of the floating point and complex number.

      []PP
10
      1%3
0.3333333333
      []PP<-6
      1%3
0.333333
      []PP
10
      2j3%3
0.6666666667j1
      []PP<-6
      2j3%3
0.666667j1

Except floating point and complex number, []PP does not take effect on integer and any other types.

      []PP<-1
      333
333
      333.0
3e2