odm/include/basedata.h

#pragma once
#include "comdefs.h"
#include <vector>

using michlib::real;

class BaseParameters
{
 public:
 virtual ~BaseParameters();
};

class BaseData
{
 protected:
 static constexpr real fillval = 1.0e10;
 std::vector<real>     data;
 std::vector<real>     lons, lats;

 BaseData(size_t n): data(n), lons(n), lats(n) {}

 template<class Lon, class Lat> BaseData(size_t n, Lon genlon, Lat genlat): data(n), lons(n), lats(n)
 {
  for(size_t i = 0; i < n; i++)
  {
   lons[i] = genlon(i);
   lats[i] = genlat(i);
  }
 };

 public:
 BaseData() = default;

 const real& V(size_t i) const { return data[i]; }
 real&       V(size_t i) { return data[i]; }

 const real& operator()(size_t i) const { return data[i]; }
 real&       operator()(size_t i) { return data[i]; }

 real Lon(size_t i) const { return lons[i]; }
 real Lat(size_t i) const { return lats[i]; }

 size_t N() const { return data.size(); }

 bool IsFill(size_t i) const { return V(i) == Fillval(); }

 static real Fillval() { return fillval; }

 explicit operator bool() const { return N() != 0; }
};

template<class T>
concept HaveU = requires(T t) {
 {
  t.template U(0)
 } -> std::convertible_to<real>;
};

template<class T>
concept HaveV = requires(T t) {
 {
  t.template V(0)
 } -> std::convertible_to<real>;
};

template<class Data> class Averager: public Data
{
 std::vector<size_t>   count;
 static constexpr bool haveu = HaveU<Data>;
 static constexpr bool havev = HaveV<Data>;

 static bool DataOk(const Data* d, size_t i)
 {
  bool uok = true;
  bool vok = true;
  if constexpr(haveu) uok = d->U(i) != Data::Fillval();
  if constexpr(havev) uok = d->V(i) != Data::Fillval();
  return uok && vok;
 }

 public:
 void Add(const Data& d)
 {
  if(!d) return;
  if(!*this)
  {
   *static_cast<Data*>(this) = d;
   count.resize(Data::N());
   for(size_t i = 0; i < Data::N(); i++) count[i] = DataOk(this, i) ? 1 : 0;
   return;
  }

  if(Data::N() != d.N()) return;
  for(size_t i = 0; i < Data::N(); i++)
   if(DataOk(&d, i))
   {
    if(DataOk(this, i))
    {
     if constexpr(haveu) Data::U(i) += d.U(i);
     if constexpr(havev) Data::V(i) += d.V(i);
     count[i]++;
    }
    else
    {
     if constexpr(haveu) Data::U(i) = d.U(i);
     if constexpr(havev) Data::V(i) = d.V(i);
     count[i] = 1;
    }
   }
 }

 Averager& Div()
 {
  if(!*this) return *this;
  for(size_t i = 0; i < Data::N(); i++)
  {
   if constexpr(haveu)
   {
    if(count[i] != 0) Data::U(i) /= count[i];
   }
   if constexpr(havev)
   {
    if(count[i] != 0) Data::V(i) /= count[i];
   }
  }
  return *this;
 }
};