lxidnt |
Table of contents
ProcedureLXIDNT ( Lex identifier ) ENTRY LXIDNT ( IDSPEC, STRING, FIRST, LAST, NCHAR ) AbstractScan an identifier, starting from a specified character position. Required_ReadingNone. KeywordsCHARACTER PARSING SCANNING STRING UTILITY DeclarationsIMPLICIT NONE INTEGER LBCELL PARAMETER ( LBCELL = -5 ) INTEGER IDSPEC ( LBCELL : * ) CHARACTER*(*) STRING INTEGER FIRST INTEGER LAST INTEGER NCHAR Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- IDSPEC I Identifier character specification. STRING I String to be scanned. FIRST I Character position at which to start scanning. LAST O Character position of end of token. NCHAR O Number of characters in token. LBCELL P The SPICE cell lower bound. Detailed_InputIDSPEC is an integer cell containing a specification of the head and tail identifier character sets to be used in scanning the input argument STRING. IDSPEC should be obtained by calling LXDFID or LXCSID. The structure of IDSPEC is not part of the specification of this routine suite and should not be relied upon by calling code. STRING is a character string that may contain an `identifier' starting at the character position indicated by the input argument FIRST (see below). Identifier tokens are sequences of characters that represent names. Syntactically, an identifier is a sequence of characters that begins with a character belonging to a set of valid `head' characters and is followed by zero or more characters belonging to a set of valid `tail' characters. FIRST is the character position at which the routine is to start scanning an identifier. Note that the character STRING(FIRST:FIRST) must be a valid head character if an identifier is to be found; this routine does *not* attempt to locate the first identifier following the position FIRST. Detailed_OutputLAST is the last character position such that the substring STRING(FIRST:LAST) is an identifier, if such a substring exists. Otherwise, the returned value of LAST is FIRST-1. NCHAR is the length of the identifier found by this routine, if such a token exists. If an identifier is not found, the returned value of NCHAR is zero. ParametersLBCELL is the SPICE cell lower bound. ExceptionsError free. 1) If the input argument FIRST is less than 1 or greater than LEN(STRING)-1, the returned value of LAST is FIRST-1, and the returned value of NCHAR is zero. FilesNone. ParticularsThe default syntax rules for valid identifiers are specified in the $Particulars section of the umbrella routine LXNAME. These rules may be overridden by calling LXCSID. ExamplesSee the $Examples section of the umbrella routine LXNAME. RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) B.V. Semenov (JPL) VersionSPICELIB Version 1.1.0, 26-OCT-2021 (JDR) Added IMPLICIT NONE statement. Edited the header to comply with NAIF standard. SPICELIB Version 1.0.1, 10-FEB-2014 (BVS) Added LBCELL to the $Declarations, $Brief_I/O, and $Parameters sections. SPICELIB Version 1.0.0, 25-OCT-1995 (NJB) |
Fri Dec 31 18:36:33 2021