xfc

Section: User Commands (1)
Updated: 10 Sep 2001
Index

NAME

xfc - xfl to C compiler

SYNOPSIS

xfc [ -M[a|e] ] [ -O opsfile ] [ -o outprefix ] [ -e engname ] [ -t ftype ] [ -w ] xflfile

DESCRIPTION

xfc takes an xfl file and produces a C source file which implements the fuzzy inference engine defined in xfl as a C function. This file can be freely combined with any other modules to produce programs containing fuzzy logic capabilities.

The only requirement that the C output file generated by xfc imposes is that it must be compiled using the libm.a library, since it uses specific mathematical functions. The C interface offered by the output of xfc is based on a function which implements the fuzzy inference engine defined by the xfl source specification. This function returns a non-zero value in case of any error and a zero otherwise. Parameters are passed to the function by reference (of type (FUZZY *), as stated by ftype) in the same order they are declared in the system module of the xfl source. Upon return, the values of those parameters identified as outputs from the xfl-based fuzzy system are updated according to its definition.

OPTIONS

-M: Selects the mode of operation: a performs only the syntax and (static) semantics analysis of the xfl source, without producing any output. e (which is the default if no -M option is specified) produces the C code for the inference engine.
-O opsfile: Use opsfile as the fuzzy operations file. By default, either the user's operations file ("$HOME/.xfcops") or a system-wide file ("$XFUZZY_LIB/xfcops", where $XFUZZY_LIB is the directory holding the Xfuzzy libraries distribution) is used. The operations file allows the use of specific definitions of T-norms (for the #and operator in xfl), T-conorms (for the #or, #also and #composition operators in xfl), negation functions (for the #not operator in xfl), implication functions (for the #implication operator in xfl) and defuzzification methods (for the #defuzzification operator in xfl). If no operations file can be accessed, xfc provides a set of internally defined fuzzy operations: the T-norm _sd_min (implementing the standard minimum operator), the T-conorm _sd_max (implementing the standard maximum operator), the negation _sd_not (implementing the 1-complement operator), the implication _sd_min (standard minimum again), and the defuzzification method _sd_CoA (the standard center-of-area method). Furthermore, these are the values used by xfc when any of the xfl operation selection operators is not present in the source file.
-o outprefix: Use outprefix as the prefix for the output file. This prefix is prepended to the string "Ie.c" to produce the output file name. Any valid path component can be used. The default value is "./a.xf".
-e engname: Use engname as the name of the function implementing the fuzzy inference engine. Any valid C function identifier can be used. The default value is "__FiEngine".
-t ftype: Use ftype as the type of fuzzy variables (specially, of the parameters to the inference engine function) within the output file. Any valid C type identifier can be used as value, since the value of this option is used in a "typedef FUZZY ftype" construct. The default value is "double".
-w: Suppresses the printing of warning messages on stderr.

FILES

$HOME/.xfcops: User's operations file (overriden by the -O option)
$XFUZZY_LIB/xfcops: System-wide operations file (overriden by the user's operations file and the -O option)