Merge pull request #6 from samharrison7/scalar_var

Adding ability to create scalar variables

README.md

@@ -26,7 +26,7 @@ use mo_netcdf, only: NcDataset, NcDimension, NcVariable, NcGroup
 
 type(NcDataset)   :: nc
 type(NcDimension) :: dim1, dim2, dim3
-type(NcVariable)  :: var
+type(NcVariable)  :: var, scalar
 type(NcGroup)     :: grp
 
 ! some data
@@ -59,8 +59,9 @@ dim3 = grp%setDimension("x", nx)
 ! args:
 !     variable name
 !     data type (currently available: "i8", "i16", "i32", "f32", "f64")
-!     dimensions array
+!     dimensions array (optional: skip for a scalar)
 var = grp%setVariable("data", "i32", (/dim3, dim2, dim1/))
+scalar = grp%setVariable("scalar", "i32")
 
 ! define a fill value
 ! args:

src/mo_netcdf.f90

@@ -130,11 +130,13 @@ module mo_netcdf
      procedure, private :: setVariableWithTypes
      procedure, private :: setVariableWithNames
      procedure, private :: setVariableWithIds
+     procedure, private :: setVariableScalar
 
      generic,   public  :: setVariable => &
           setVariableWithNames, &
           setVariableWithTypes, &
-          setVariableWithIds
+          setVariableWithIds, &
+          setVariableScalar
 
   end type NcGroup
 
@@ -703,6 +705,18 @@ function setVariableWithTypes(self, name, dtype, dimensions, contiguous, &
          cache_size, cache_nelems, cache_preemption)
   end function setVariableWithTypes
 
+  function setVariableScalar(self, name, dtype)
+    class(NcGroup)  , intent(in)           :: self
+    character(*)    , intent(in)           :: name
+    character(*)    , intent(in)           :: dtype
+    type(NcVariable)                       :: setVariableScalar
+    integer(i32)                           :: varid, status
+
+    status = nf90_def_var(self%id, name, getDtypeFromString(dtype), varid=varid)
+    call check(status, "Failed to create variable: " // name)
+    setVariableScalar = NcVariable(varid, self)
+  end function setVariableScalar
+
   function getDimensionById(self, id)
     class(NcGroup), intent(in) :: self
     integer(i32)                  :: id

tests/test_setdata.f90

@@ -7,7 +7,7 @@ program test_putdata
   use mo_testhelper
 
   type(NcDataset)   :: nc
-  type(NcVariable)  :: var
+  type(NcVariable)  :: var, scalar
 
   integer(i32), parameter   :: nx=10, ny=20, ntime=8
   integer(i32)              :: val
@@ -21,13 +21,19 @@ program test_putdata
        "i32",  &
        [nc%setDimension("x", nx), nc%setDimension("y", ny), nc%setDimension("time")] &
   )
+  scalar = nc%setVariable("scalar", "i32")
 
   ! set and get a single value
   ! i.e. (5,5)
   call var%setData(42, start=[5,5])
   call var%getData(val, start=[5,5])
   call assertEqual(val, 42, "Failed to set a scalar value!")
 
+  ! set and get a scalar
+  call scalar%setData(42)
+  call scalar%getData(val)
+  call assertEqual(val, 42, "Failed to set a scalar value!")
+
   ! set and get the all values for the first row in the third timestep
   ! i.e. (:,1,3)
   write1d = full(nx, 21_i32)