Merge pull request #4498 from evoyiatzis/patch-4

implement extract() in pair_style yukawa

doc/src/fix_adapt.rst

@@ -236,6 +236,8 @@ formulas for the meaning of these parameters:
 +------------------------------------------------------------------------------+--------------------------------------------------+-------------+
 | :doc:`wf/cut <pair_wf_cut>`                                                  | epsilon,sigma,nu,mu                              | type pairs  |
 +------------------------------------------------------------------------------+--------------------------------------------------+-------------+
+| :doc:`yukawa <pair_yukawa>`                                                  | alpha                                            | type pairs  |
++------------------------------------------------------------------------------+--------------------------------------------------+-------------+
 
 .. note::
 

src/pair_yukawa.cpp

@@ -332,3 +332,12 @@ double PairYukawa::single(int /*i*/, int /*j*/, int itype, int jtype, double rsq
   phi = a[itype][jtype] * screening * rinv - offset[itype][jtype];
   return factor_lj * phi;
 }
+
+/* ---------------------------------------------------------------------- */
+
+void *PairYukawa::extract(const char *str, int &dim)
+{
+  dim = 2;
+  if (strcmp(str, "alpha") == 0) return (void *) a;
+  return nullptr;
+}

src/pair_yukawa.h

@@ -39,6 +39,7 @@ class PairYukawa : public Pair {
   void write_data(FILE *) override;
   void write_data_all(FILE *) override;
   double single(int, int, int, int, double, double, double, double &) override;
+  void *extract(const char *, int &) override;
 
  protected:
   double cut_global;

unittest/force-styles/tests/mol-pair-yukawa.yaml

@@ -17,7 +17,8 @@ pair_coeff: ! |
   3 3 350.0
   4 4 250.0
   5 5 250.0
-extract: ! ""
+extract: ! |
+  alpha 2
 natoms: 29
 init_vdwl: 12.114009254533281
 init_coul: 0