Do not use type snapshot in program `inst_eddies`

This was not useful since we do not need an array of snapshots in
`inst_eddies`. It is clearer without the integration in a snapshot
variable. The integration in a snapshot variable came from initial
commit, when there was only one program for detection of instantaneous
eddies and overlapping.

Inst_eddies/inst_eddies.f90

@@ -11,7 +11,7 @@ program inst_eddies
   use numer_rec_95, only: indexx
 
   use config_m, only: config, max_radius
-  use derived_types, only: snapshot, shpc_slice_handler
+  use derived_types, only: eddy, shpc_slice_handler
   use input_ssh_m, only: input_ssh, nlon, nlat
   use nearby_extr_m, only: nearby_extr
   use set_all_extr_m, only: set_all_extr
@@ -23,7 +23,20 @@ program inst_eddies
 
   implicit none
 
-  type(snapshot) s
+  type(eddy), allocatable:: list(:) ! (number_extr) "Eddies" at a
+  ! given date. In general, there may be both cyclonic and
+  ! anticyclonic eddies in the list. Eddies include "eddies"
+  ! without an outermost contour, that is, only the extremum is
+  ! defined. The subscript value in list is the "identification
+  ! number" of the extremum.
+
+  integer number_extr ! number of extrema
+
+  integer, allocatable:: extr_map(:, :)
+  ! (1 - max_radius(1):nlon + max_radius(1), nlat) if the grid is
+  ! periodic in longitude, else (nlon, nlat). At a point of extremum
+  ! SSH: identification number or this extremum. 0 at other points.
+
   TYPE(shpc_slice_handler) hshpc_cyclo, hshpc_anti
   integer iostat, i, l
   character(len = 200) iomsg
@@ -46,7 +59,7 @@ program inst_eddies
   integer:: date = 0, slice = 0
   namelist /dates_nml/ date, slice
 
-  integer, allocatable:: sorted_extr(:) ! (s%number_extr)
+  integer, allocatable:: sorted_extr(:) ! (number_extr)
   ! Sorted identifying number of extrema: first, minima sorted in
   ! order of decreasing SSH, and second, maxima sorted in order of
   ! increasing SSH.
@@ -112,35 +125,35 @@ program inst_eddies
   write(unit, fmt = *) "CPU time for preamble, before computation:", t1 - t0, &
        "s"
   t0 = t1
-  call set_all_extr(s%extr_map, s%list, step, periodic, ssh)
-  s%number_extr = size(s%list)
-  allocate(sorted_extr(s%number_extr))
+  call set_all_extr(extr_map, list, step, periodic, ssh)
+  number_extr = size(list)
+  allocate(sorted_extr(number_extr))
 
-  forall (i = 1:s%number_extr)
-     s%list(i)%out_cont%closed = .true.
+  forall (i = 1:number_extr)
+     list(i)%out_cont%closed = .true.
      ! must be intialized to true because it is used in nearby_extr
   end forall
 
   ! Double sort of extrema on cyclonicity and SSH value:
 
-  selection = argwhere(s%list%cyclone)
+  selection = argwhere(list%cyclone)
   n_cycl = size(selection)
-  selection = selection(indexx(s%list(selection)%extr%ssh))
+  selection = selection(indexx(list(selection)%extr%ssh))
   sorted_extr(:n_cycl) = selection(n_cycl:1:- 1) ! descending order of ssh
 
-  selection = argwhere(.not. s%list%cyclone)
-  selection = selection(indexx(s%list(selection)%extr%ssh))
+  selection = argwhere(.not. list%cyclone)
+  selection = selection(indexx(list(selection)%extr%ssh))
   sorted_extr(n_cycl + 1:) = selection
 
   ! Done sorting
 
-  do l = 1, s%number_extr
+  do l = 1, number_extr
      i = sorted_extr(l)
 
      ! Define the geographical window around each eddy extremum:
 
-     llc = s%list(i)%extr%coord_proj - max_radius
-     urc = s%list(i)%extr%coord_proj + max_radius
+     llc = list(i)%extr%coord_proj - max_radius
+     urc = list(i)%extr%coord_proj + max_radius
 
      llc(2) = max(llc(2), 1)
      urc(2) = min(urc(2), nlat)
@@ -153,16 +166,16 @@ program inst_eddies
      ! Done defining geographical window
 
      outside_points &
-          = nearby_extr(s%extr_map(llc(1):urc(1), llc(2):urc(2)), s%list, i)
+          = nearby_extr(extr_map(llc(1):urc(1), llc(2):urc(2)), list, i)
 
      ! Shift the x coordinate of each point to a value close to the
      ! coordinate of the target extremum:
      if (periodic) outside_points(1, :) = outside_points(1, :) &
           + ceiling((llc(1) - outside_points(1, :)) / real(nlon)) * nlon
 
-     call set_contours(s%list(i)%out_cont, s%list(i)%speed_cont, &
-          s%list(i)%max_speed, s%list(i)%cyclone, s%list(i)%extr, &
-          s%list(i)%innermost_level, step, ssh(llc(1):urc(1), llc(2):urc(2)), &
+     call set_contours(list(i)%out_cont, list(i)%speed_cont, &
+          list(i)%max_speed, list(i)%cyclone, list(i)%extr, &
+          list(i)%innermost_level, step, ssh(llc(1):urc(1), llc(2):urc(2)), &
           u(llc(1):urc(1), llc(2):urc(2)), v(llc(1):urc(1), llc(2):urc(2)), &
           llc, outside_points)
   end do
@@ -170,8 +183,8 @@ program inst_eddies
   call cpu_time(t1)
   write(unit, fmt = *) "CPU time for computation, before output:", t1 - t0, "s"
   t0 = t1
-  print *, "inst_eddies: s%number_extr = ", s%number_extr
-  call write_snapshot(s%list, hshpc_cyclo, hshpc_anti, date)
+  print *, "inst_eddies: number_extr = ", number_extr
+  call write_snapshot(list, hshpc_cyclo, hshpc_anti, date)
   CALL shpc_close(hshpc_cyclo)
   CALL shpc_close(hshpc_anti)