Added TimeData structure for easy calculation of time column parameters of netcdf files.

Also, one-index version of Read() function.

include/actiondep.h

@@ -5,6 +5,8 @@
 #include "mregex.h"
 #include "traits.h"
 #include "uvdata.h"
+#include <array>
+#include <utility>
 
 using michlib::MDateTime;
 
@@ -21,6 +23,41 @@ using michlib::MDateTime;
  };
 #endif
 
+struct TimeData
+{
+ static constexpr auto                                            stepunits = std::to_array<uint>({3600 * 24, 3600, 60, 1});
+ static constexpr std::array<const std::string, stepunits.size()> stepnames{"days", "hours", "minutes", "seconds"};
+
+ MDateTime                  refdate;
+ size_t                     unitind;
+ std::vector<michlib::int4> steps;
+
+ template<class D> TimeData(const D& data, const TIndex& tindexes): refdate(), unitind(stepunits.size()), steps(tindexes.size())
+ {
+  if(steps.size() == 0) return;
+  refdate = data.Time(tindexes[0]);
+  unitind = 0;
+
+  for(size_t i = 0; i < steps.size(); i++)
+  {
+   auto delta = data.Time(tindexes[i]) - refdate;
+   while(delta % stepunits[unitind] != 0) unitind++;
+  }
+
+  for(size_t i = 0; i < steps.size(); i++)
+  {
+   auto delta = data.Time(tindexes[i]) - refdate;
+   steps[i]   = michlib::int_cast<decltype(steps)::value_type>(delta / stepunits[unitind]);
+  }
+ }
+
+ MString UnitName() const
+ {
+  MString out = stepnames[unitind].c_str();
+  return out + " since " + refdate.ToString();
+ }
+};
+
 template<class D> size_t GetTIndex(const D& data, const MDateTime& t)
 {
  size_t nt = data.NTimes();
@@ -98,27 +135,33 @@ template<class D> std::pair<TIndex, MString> GetTIndexes(const D& data, const CL
  return {tindexes, ""};
 }
 
+template<class D> std::vector<ReadType<D>> Read(const D& data, const std::vector<MString>& vnames, const BaseParameters* p, size_t ind)
+{
+ using RT = ReadType<D>;
+ std::vector<RT> out;
+ michlib::message("Time: " + data.Time(ind).ToTString());
+ std::map<MString, RT> cache;
+ for(const auto& vname: vnames)
+ {
+  bool res;
+  if constexpr(ReadPSupported<D>)
+   res = data.Read(vname, cache, p, ind);
+  else if constexpr(ReadSupported<D>)
+   res = data.Read(vname, cache, ind);
+  if(!res) return out;
+ }
+ for(size_t i = 0; i < vnames.size(); i++) out.emplace_back(std::move(cache[vnames[i]]));
+
+ return out;
+}
+
 template<class D> std::vector<ReadType<D>> Read(const D& data, const std::vector<MString>& vnames, const BaseParameters* p, const TIndex& tindex)
 {
  using RT = ReadType<D>;
  size_t          ind;
  std::vector<RT> out;
  if(tindex.size() == 1)
- {
-  ind = tindex[0];
-  michlib::message("Time: " + data.Time(ind).ToTString());
-  std::map<MString, RT> cache;
-  for(const auto& vname: vnames)
-  {
-   bool res;
-   if constexpr(ReadPSupported<D>)
-    res = data.Read(vname, cache, p, ind);
-   else if constexpr(ReadSupported<D>)
-    res = data.Read(vname, cache, ind);
-   if(!res) return out;
-  }
-  for(size_t i = 0; i < vnames.size(); i++) out.emplace_back(std::move(cache[vnames[i]]));
- }
+  return Read(data, vnames, p, tindex[0]);
  else
  {
   std::vector<Averager<RT>> aver(vnames.size());