- normal() respects the "level" parameter to limit the recursion depth

[ginac.git] / ginac / inifcns.cpp

diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp
index e8531a062e8e7d6b2baed72620c23006c48ff8c8..85a7365fa980ece03a596b9b9cff70724c8da529 100644 (file)
--- a/ginac/inifcns.cpp
+++ b/ginac/inifcns.cpp
@@ -65,6 +65,67 @@ static ex abs_eval(const ex & x)
 REGISTER_FUNCTION(abs, eval_func(abs_eval).
                        evalf_func(abs_evalf));
 
+
+//////////
+// Complex sign
+//////////
+
+static ex csgn_evalf(const ex & x)
+{
+    BEGIN_TYPECHECK
+        TYPECHECK(x,numeric)
+    END_TYPECHECK(csgn(x))
+    
+    return csgn(ex_to_numeric(x));
+}
+
+static ex csgn_eval(const ex & x)
+{
+    if (is_ex_exactly_of_type(x, numeric))
+        return csgn(ex_to_numeric(x));
+    
+    else if (is_ex_exactly_of_type(x, mul)) {
+        numeric oc = ex_to_numeric(x.op(x.nops()-1));
+        if (oc.is_real()) {
+            if (oc > 0)
+                // csgn(42*x) -> csgn(x)
+                return csgn(x/oc).hold();
+            else
+                // csgn(-42*x) -> -csgn(x)
+                return -csgn(x/oc).hold();
+        }
+        if (oc.real().is_zero()) {
+            if (oc.imag() > 0)
+                // csgn(42*I*x) -> csgn(I*x)
+                return csgn(I*x/oc).hold();
+            else
+                // csgn(-42*I*x) -> -csgn(I*x)
+                return -csgn(I*x/oc).hold();
+        }
+       }
+   
+    return csgn(x).hold();
+}
+
+static ex csgn_series(const ex & x, const relational & rel, int order)
+{
+    const ex x_pt = x.subs(rel);
+    if (x_pt.info(info_flags::numeric)) {
+        if (ex_to_numeric(x_pt).real().is_zero())
+            throw (std::domain_error("csgn_series(): on imaginary axis"));
+        epvector seq;
+        seq.push_back(expair(csgn(x_pt), _ex0()));
+        return pseries(rel,seq);
+    }
+    epvector seq;
+    seq.push_back(expair(csgn(x_pt), _ex0()));
+    return pseries(rel,seq);
+}
+
+REGISTER_FUNCTION(csgn, eval_func(csgn_eval).
+                        evalf_func(csgn_evalf).
+                        series_func(csgn_series));
+
 //////////
 // dilogarithm
 //////////
@@ -158,12 +219,14 @@ static ex Order_eval(const ex & x)
        return Order(x).hold();
 }
 
-static ex Order_series(const ex & x, const symbol & s, const ex & point, int order)
+static ex Order_series(const ex & x, const relational & r, int order)
 {
        // Just wrap the function into a pseries object
        epvector new_seq;
-       new_seq.push_back(expair(Order(_ex1()), numeric(min(x.ldegree(s), order))));
-       return pseries(s, point, new_seq);
+    GINAC_ASSERT(is_ex_exactly_of_type(r.lhs(),symbol));
+    const symbol *s = static_cast<symbol *>(r.lhs().bp);
+       new_seq.push_back(expair(Order(_ex1()), numeric(min(x.ldegree(*s), order))));
+       return pseries(r, new_seq);
 }
 
 // Differentiation is handled in function::derivative because of its special requirements
@@ -171,41 +234,19 @@ static ex Order_series(const ex & x, const symbol & s, const ex & point, int ord
 REGISTER_FUNCTION(Order, eval_func(Order_eval).
                          series_func(Order_series));
 
-//////////
-// Inert differentiation
-//////////
-
-static ex Diff_eval(const ex & f, const ex & x)
-{
-       return Diff(f, x).hold();
-}
-
-static ex Diff_deriv(const ex & f, const ex & x, unsigned deriv_param)
-{
-       GINAC_ASSERT(deriv_param == 0 || deriv_param == 1);
-       if (deriv_param == 1)
-               return Diff(Diff(f, x), x);
-       else
-               return _ex0();
-}
-
-REGISTER_FUNCTION(Diff, eval_func(Diff_eval).
-                        derivative_func(Diff_deriv));
-
 //////////
 // Inert partial differentiation operator
 //////////
 
-static ex Derivative_eval(const ex & f, const ex & n)
+static ex Derivative_eval(const ex & f, const ex & l)
 {
-       if (is_ex_exactly_of_type(n, numeric) && ex_to_numeric(n).is_nonneg_integer()) {
-               unsigned i = ex_to_numeric(n).to_int();
-               if (is_ex_exactly_of_type(f, function)) {
-                       if (i < f.nops() && is_ex_exactly_of_type(f.op(i), symbol))
-                               return Diff(f, f.op(i));
-               }
+       if (!is_ex_exactly_of_type(f, function)) {
+        throw(std::invalid_argument("Derivative(): 1st argument must be a function"));
        }
-       return Derivative(f, n).hold();
+    if (!is_ex_exactly_of_type(l, lst)) {
+        throw(std::invalid_argument("Derivative(): 2nd argument must be a list"));
+    }
+       return Derivative(f, l).hold();
 }
 
 REGISTER_FUNCTION(Derivative, eval_func(Derivative_eval));
@@ -321,7 +362,7 @@ ex ncpower(const ex &basis, unsigned exponent)
 
 /** Force inclusion of functions from initcns_gamma and inifcns_zeta
  *  for static lib (so ginsh will see them). */
-unsigned force_include_gamma = function_index_Gamma;
+unsigned force_include_tgamma = function_index_tgamma;
 unsigned force_include_zeta1 = function_index_zeta1;
 
 #ifndef NO_NAMESPACE_GINAC