Commit 2ed0803c authored by Stefano Sabatini's avatar Stefano Sabatini

lavu/eval: extend if/ifnot functions to accept a third parameter

Add support to an if/else construct, simplify logic in expressions.
parent 056664ff
......@@ -151,10 +151,18 @@ Return the greatest common divisor of @var{x} and @var{y}. If both @var{x} and
Evaluate @var{x}, and if the result is non-zero return the result of
the evaluation of @var{y}, return 0 otherwise.
@item if(x, y, z)
Evaluate @var{x}, and if the result is non-zero return the evaluation
result of @var{y}, otherwise the evaluation result of @var{z}.
@item ifnot(x, y)
Evaluate @var{x}, and if the result is zero return the result of the
evaluation of @var{y}, return 0 otherwise.
@item ifnot(x, y, z)
Evaluate @var{x}, and if the result is zero return the evaluation
result of @var{y}, otherwise the evaluation result of @var{z}.
@item taylor(expr, x) taylor(expr, x, id)
Evaluate a taylor series at x.
expr represents the LD(id)-th derivates of f(x) at 0. If id is not specified
......
......@@ -180,8 +180,10 @@ static double eval_expr(Parser *p, AVExpr *e)
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_if: return e->value * ( eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : 0);
case e_ifnot: return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) : 0);
case e_if: return e->value * (eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) :
e->param[2] ? eval_expr(p, e->param[2]) : 0);
case e_ifnot: return e->value * (!eval_expr(p, e->param[0]) ? eval_expr(p, e->param[1]) :
e->param[2] ? eval_expr(p, e->param[2]) : 0);
case e_random:{
int idx= av_clip(eval_expr(p, e->param[0]), 0, VARS-1);
uint64_t r= isnan(p->var[idx]) ? 0 : p->var[idx];
......@@ -599,6 +601,8 @@ static int verify_expr(AVExpr *e)
case e_not:
case e_random:
return verify_expr(e->param[0]) && !e->param[1];
case e_if:
case e_ifnot:
case e_taylor:
return verify_expr(e->param[0]) && verify_expr(e->param[1])
&& (!e->param[2] || verify_expr(e->param[2]));
......@@ -777,8 +781,12 @@ int main(int argc, char **argv)
"PI^1.23",
"pow(-1,1.23)",
"if(1, 2)",
"if(1, 1, 2)",
"if(0, 1, 2)",
"ifnot(0, 23)",
"ifnot(1, NaN) + if(0, 1)",
"ifnot(1, 1, 2)",
"ifnot(0, 1, 2)",
"taylor(1, 1)",
"taylor(eq(mod(ld(1),4),1)-eq(mod(ld(1),4),3), PI/2, 1)",
"root(sin(ld(0))-1, 2)",
......
......@@ -76,7 +76,7 @@
#define LIBAVUTIL_VERSION_MAJOR 52
#define LIBAVUTIL_VERSION_MINOR 15
#define LIBAVUTIL_VERSION_MICRO 101
#define LIBAVUTIL_VERSION_MICRO 102
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
LIBAVUTIL_VERSION_MINOR, \
......
......@@ -205,12 +205,24 @@ Evaluating 'pow(-1,1.23)'
Evaluating 'if(1, 2)'
'if(1, 2)' -> 2.000000
Evaluating 'if(1, 1, 2)'
'if(1, 1, 2)' -> 1.000000
Evaluating 'if(0, 1, 2)'
'if(0, 1, 2)' -> 2.000000
Evaluating 'ifnot(0, 23)'
'ifnot(0, 23)' -> 23.000000
Evaluating 'ifnot(1, NaN) + if(0, 1)'
'ifnot(1, NaN) + if(0, 1)' -> 0.000000
Evaluating 'ifnot(1, 1, 2)'
'ifnot(1, 1, 2)' -> 2.000000
Evaluating 'ifnot(0, 1, 2)'
'ifnot(0, 1, 2)' -> 1.000000
Evaluating 'taylor(1, 1)'
'taylor(1, 1)' -> 2.718282
......
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