HP 39gII, Руководство пользователя

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Programming 275
left Syntax:
left
( str,n )
Return the first n characters of string str . If
or , returns str . If n == 0 returns the empty string.
Example:
left
( "MOMOGUMBO",3 ) returns "MOM"
right Syntax: right( str,n )
Returns the last n characters of string str . If n <= 0, returns
empty string. If n > - dim ( str ), returns str
Example:
right
("MOMOGUMBO",5) returns
"GUMBO"
mid Syntax:
mid
( str,pos, [ n ])
Extracts n characters from string str starting at index pos.
n is optional, if not specified, extracts all the remainder of
the string.
Example:
mid
( "MOMOGUMBO",3,5 ) returns
"MOGUM",
mid
( "PUDGE",4 ) returns "GE"
rotate Syntax:
rotate
( str,n )
Permutation of characters in string str . If 0<= n < dim ( str ),
shifts n places to left. If -dim ( str )< n <=-1, shifts n spaces to
right. If n > dim ( str ) or n < -dim ( str ), returns str .
Examples:
rotate
( "12345",2 ) returns "34512"
rotate
( "12345",-1 ) returns "51234"
rotate
( "12345",6 ) returns "12345"
Test Commands
The Test commands include both Boolean and relational
operations. Boolean and relational expressions evaluate
to true or false. A non-zero number is equivalent to true,
and a number equal to 0 is equivalent to false. Note that
in addition to real numbers, complex numbers, strings,
lists, and matrices can be compared using the relational
operators ==, NOT (or !=), and (or <> or !=). These
commands are not in the CMDS menu. They appear in
the Math menu but are listed here for convenience.
n dim str
( ) ≥
n 0
<