From: Richard Kreckel <kreckel@ginac.de>
Date: Thu, 14 Apr 2016 19:29:37 +0000 (+0200)
Subject: Add fderivative::derivatives() method.
X-Git-Tag: release_1-7-0~3
X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=commitdiff_plain;h=90cec97dc7de15159ce50bbcc95fdff5179bad48

Add fderivative::derivatives() method.
---

diff --git a/NEWS b/NEWS
index aa6d33c7..fba9480f 100644
--- a/NEWS
+++ b/NEWS
@@ -26,6 +26,7 @@ This file records noteworthy changes.
   modeled after the .eval() methods.
 * Make relational::rhs() and lhs() nonvirtual.
 * Add support for power::info(info_flags::real).
+* Add fderivative::derivatives() method.
 * Remove broken info_flags::algebraic.
 * Remove unmaintained support for Cint.
 * Remove unfinished andcode for hash table-based expairseq.
diff --git a/ginac/fderivative.cpp b/ginac/fderivative.cpp
index 9e3c981a..2ce60fb3 100644
--- a/ginac/fderivative.cpp
+++ b/ginac/fderivative.cpp
@@ -215,4 +215,20 @@ bool fderivative::match_same_type(const basic & other) const
 	return parameter_set == o.parameter_set && inherited::match_same_type(other);
 }
 
+/** Expose this object's derivative structure.
+ *
+ *  Parameter numbers occurring more than once stand for repeated
+ *  differentiation with respect to that parameter. If a symbolic function
+ *  f(x,y) is differentiated with respect to x, this method will return {0}.
+ *  If f(x,y) is differentiated twice with respect to y, it will return {1,1}.
+ *  (This corresponds to the way this object is printed.)
+ *
+ *  @return  multiset of function's parameter numbers that are abstractly
+ *  differentiated. */
+const paramset& fderivative::derivatives() const
+{
+	return parameter_set;
+}
+
+
 } // namespace GiNaC
diff --git a/ginac/fderivative.h b/ginac/fderivative.h
index 70f65ec4..fe7abe81 100644
--- a/ginac/fderivative.h
+++ b/ginac/fderivative.h
@@ -72,6 +72,8 @@ protected:
 	bool match_same_type(const basic & other) const override;
 
 	// non-virtual functions in this class
+public:
+	const paramset& derivatives() const;
 protected:
 	void do_print(const print_context & c, unsigned level) const;
 	void do_print_csrc(const print_csrc & c, unsigned level) const;