INDEX(3F)INDEX(3F)NAME
index, rindex, lnblnk, len - get index or length of substring
SYNOPSIS/USAGE
CHARACTER*(*) string, substr
n = INDEX (string, substr)
INTEGER*4 FUNCTION rindex
CHARACTER*(*) string, substr
n = rindex (string, substr)
INTEGER*4 FUNCTION lnblnk
CHARACTER*(*) string
n = lnblnk (string)
CHARACTER*(*) string
n = LEN (string)
DESCRIPTION
INDEX(a1,a2) returns the index of the first occurrence of string a2 in
string a1, or zero if it does not occur (intrinsic function).
rindex(a1,a2) returns the index of the last occurrence of string a2 in
string a1, or zero if it does not occur.
lnblnk( a1 ) returns the index of the last non-blank character in a1.
This function is useful since all f77 character objects are of fixed
length and blank-padded.
LEN returns the declared size of the character string argument (intrin‐
sic function).
NOTES
When compiling for 64-bit environments (with compiler option -m64 rou‐
tines len, index, rindex, and lnblnk could return values greater than
the data range of INTEGER*4 data when applied to very large character
strings (greater than 2 Gbytes). In this situation, these functions
must be declared INTEGER*8, as well as the variables receiving their
results.
EXAMPLE
Example: LEN(), INDEX(), rindex() , lnblnk():
CHARACTER s*32 / '123456789 123456789 1234' /
INTEGER*4 declen, first, last, lnblnk, rindex
declen = LEN( s )
first = INDEX( s, '123' )
last = rindex( s, '123' )
lastnb = lnblnk( s )
PRINT*, declen, lastnb, first, last
END
demo% f77 -silent tindex.f
demo% a.out
32 24 1 21
demo%
In the above example, declen is 32, not 24. This is the declared length
of the character variable, not the length of the string it contains.
FILES
libfui.a
10/02/02 INDEX(3F)
