Commit 8cee38a2 by Stefano Sabatini Committed by Anton Khirnov

### eval: implement not() expression

parent 9bc39390
 ... ... @@ -76,6 +76,9 @@ integer. For example, "trunc(-1.5)" is "-1.0". @item sqrt(expr) Compute the square root of @var{expr}. This is equivalent to "(@var{expr})^.5". @item not(expr) Return 1.0 if @var{expr} is zero, 0.0 otherwise. @end table Note that: ... ... @@ -93,11 +96,6 @@ is equivalent to A*B + not(A)*C @end example When A evaluates to either 1 or 0, that is the same as @example A*B + eq(A,0)*C @end example In your C code, you can extend the list of unary and binary functions, and define recognized constants, so that they are available for your expressions. ... ...
 ... ... @@ -41,7 +41,7 @@ #define LIBAVUTIL_VERSION_MAJOR 51 #define LIBAVUTIL_VERSION_MINOR 10 #define LIBAVUTIL_VERSION_MICRO 1 #define LIBAVUTIL_VERSION_MICRO 2 #define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \ LIBAVUTIL_VERSION_MINOR, \ ... ...
 ... ... @@ -123,7 +123,7 @@ struct AVExpr { e_mod, e_max, e_min, e_eq, e_gt, e_gte, e_pow, e_mul, e_div, e_add, e_last, e_st, e_while, e_floor, e_ceil, e_trunc, e_sqrt, e_sqrt, e_not, } type; double value; // is sign in other types union { ... ... @@ -151,6 +151,7 @@ static double eval_expr(Parser *p, AVExpr *e) case e_ceil : return e->value * ceil (eval_expr(p, e->param[0])); case e_trunc: return e->value * trunc(eval_expr(p, e->param[0])); case e_sqrt: return e->value * sqrt (eval_expr(p, e->param[0])); case e_not: return e->value * eval_expr(p, e->param[0]) == 0; case e_while: { double d = NAN; while (eval_expr(p, e->param[0])) ... ... @@ -286,6 +287,7 @@ static int parse_primary(AVExpr **e, Parser *p) else if (strmatch(next, "ceil" )) d->type = e_ceil; else if (strmatch(next, "trunc" )) d->type = e_trunc; else if (strmatch(next, "sqrt" )) d->type = e_sqrt; else if (strmatch(next, "not" )) d->type = e_not; else { for (i=0; p->func1_names && p->func1_names[i]; i++) { if (strmatch(next, p->func1_names[i])) { ... ... @@ -454,6 +456,7 @@ static int verify_expr(AVExpr *e) case e_ceil: case e_trunc: case e_sqrt: case e_not: return verify_expr(e->param[0]); default: return verify_expr(e->param[0]) && verify_expr(e->param[1]); } ... ... @@ -606,6 +609,9 @@ int main(int argc, char **argv) "ceil(-123.123)", "sqrt(1764)", "sqrt(-1)", "not(1)", "not(NAN)", "not(0)", NULL }; ... ...
 ... ... @@ -139,5 +139,14 @@ Evaluating 'sqrt(1764)' Evaluating 'sqrt(-1)' 'sqrt(-1)' -> -nan Evaluating 'not(1)' 'not(1)' -> 0.000000 Evaluating 'not(NAN)' 'not(NAN)' -> 0.000000 Evaluating 'not(0)' 'not(0)' -> 1.000000 12.700000 == 12.7 0.931323 == 0.931322575
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