doc support

C/eval.c

@@ -18,10 +18,16 @@
 static char     SccsId[] = "%W% %G%";
 #endif
 
-/*
- * This file implements arithmetic operations 
- *
- */
+/**
+   @file eval.c
+
+   @defgroup arithmetic_preds Arithmetic Predicates
+   @ingroup arithmetic
+
+   @{
+*/
+
+
 #include "Yap.h"
 #include "Yatom.h"
 #include "YapHeap.h"
@@ -184,6 +190,23 @@ BEAM_is(void)
 
 #endif
 
+/**
+   @class is_2
+   @anchor is_2
+   @brief evaluation of arithmetic expressions
+
+   <b>? _X_:number is + _Y_:ground is det</b>
+
+   This predicate succeeds iff the result of evaluating the expression
+   _Y_ unifies with  _X_. This is the predicate normally used to
+   perform evaluation of arithmetic expressions:
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+X is 2+3*4
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+    succeeds with `X = 14`.
+
+*/
+
 static Int
 p_is( USES_REGS1 )
 {				/* X is Y	 */
@@ -204,6 +227,16 @@ p_is( USES_REGS1 )
   return Yap_unify_constant(ARG1,out);
 }
 
+/**
+   @class isnan_1
+   @anchor isnan_1
+   @brief True if _X_ is not a number
+
+   <b> isnan(? _X_:float) is det</b>
+
+   Interface to the IEE754 `isnan` test.
+*/
+
 static Int
 p_isnan( USES_REGS1 )
 {				/* X is Y	 */
@@ -232,6 +265,17 @@ p_isnan( USES_REGS1 )
   return isnan(FloatOfTerm(out));
 }
 
+/**
+   @class isinf_1
+   @anchor isinf_1
+   @brief True if _X_ is infinity
+
+   <b> isnan(? _X_:float) is det</b>
+
+   Interface to the IEE754 `isinf` test.
+*/
+
+
 static Int
 p_isinf( USES_REGS1 )
 {                               /* X is Y        */
@@ -260,6 +304,18 @@ p_isinf( USES_REGS1 )
   return isinf(FloatOfTerm(out));
 }
 
+/**
+   @class logsum_3
+   @anchor logsum_3
+   @brief sum of two logarithms
+
+   <b> logsum(+ _Log1_, + _Log2_, - _Out_ ) is det </b>
+
+True if  _Log1_ is the logarithm of the positive number  _A1_,
+ _Log2_ is the logarithm of the positive number  _A2_, and
+ _Out_ is the logarithm of the sum of the numbers  _A1_ and
+ _A2_. Useful in probability computation.
+*/
 static Int
 p_logsum( USES_REGS1 )
 {                               /* X is Y        */
@@ -391,6 +447,25 @@ static Int cont_between( USES_REGS1 )
   }
 }
 
+/**
+   @class between_3
+   @anchor between_3
+   @brief sequence of numbers
+
+   between(+ _Low_:int, + _High_:int, ? _Value_:int) is nondet
+
+   _Low_ and  _High_ are integers,  _High_ \>= _Low_. If
+   _Value_ is an integer,  _Low_ =\< _Value_
+   =\< _High_. When  _Value_ is a variable it is successively
+   bound to all integers between  _Low_ and  _High_. If
+   _High_ is inf or infinite [between/3](@ref between_3) is true iff
+   _Value_ \>=  _Low_, a feature that is particularly interesting
+   for generating integers from a certain value.
+
+   @}
+
+*/
+
 static Int
 init_between( USES_REGS1 )
 {