add nc4version function

Author: scivision

API.md

@@ -0,0 +1,65 @@
+# nc4fortran Usage
+
+All examples assume:
+
+```fortran
+use nc4fortran, only: netcdf_file
+type(netcdf_file) :: hf
+```
+
+* gzip compression may be applied for rank ≥ 2 arrays by setting `comp_lvl` to a value between 1 and 9.
+  Shuffle filter is automatically applied for better compression
+* string attributes may be applied to any variable at time of writing or later.
+
+Check NetCDF4 library version:
+
+```fortran
+use nc4fortran, only: nc4version
+print *, nc4version()
+```
+
+Create new NetCDF file, with variable "value1"
+
+```fortran
+call hf%open('test.nc', action='w')
+
+call hf%write('value1', 123.)
+
+call hf%close()
+```
+
+Check if variable exists
+
+```fortran
+logical :: exists
+
+exists = hf%exist('fooname')
+```
+
+Add/append variable "value1" to existing NetCDF file "test.nc"
+
+* if file `test.nc` exists, add a variable to it
+* if file `test.nc` does not exist, create it and add a variable to it.
+
+```fortran
+call hf%open('test.nc', action='rw')
+
+call hf%write('value1', 123.)
+
+call hf%close()
+```
+
+Read scalar, 3-D array of unknown size
+
+```fortran
+call ncf%open('test.nc', action='r')
+
+integer, allocatable :: dims(:)
+real, allocatable :: A(:,:,:)
+
+call ncf%shape('foo', dims)
+allocate(A(dims(1), dims(2), dims(3)))
+call ncf%read('foo', A)
+
+call ncf%close()
+```

README.md

@@ -32,6 +32,8 @@ Tested on systems with NetCDF4 including:
 * Windows Subsystem for Linux
 * Windows Cygwin
 
+See [API](./API.md) for usage.
+
 ## Build
 
 Requirements:
@@ -78,7 +80,7 @@ include(FetchContent)
 
 FetchContent_Declare(nc4fortran_proj
   GIT_REPOSITORY https://github.com/geospace-code/nc4fortran.git
-  GIT_TAG v1.3.0)
+  GIT_TAG v1.5.0)
 
 FetchContent_MakeAvailable(nc4fortran_proj)
 
@@ -113,73 +115,7 @@ and have a file in the master project `subprojects/nc4fortran.wrap` containing:
 [wrap-git]
 directory = nc4fortran
 url = https://github.com/geospace-code/nc4fortran.git
-revision = head
-```
-
-## Usage
-
-All examples assume:
-
-```fortran
-use nc4fortran, only: netcdf_file
-type(netcdf_file) :: hf
-```
-
-* gzip compression may be applied for rank ≥ 2 arrays by setting `comp_lvl` to a value between 1 and 9.
-  Shuffle filter is automatically applied for better compression
-* string attributes may be applied to any variable at time of writing or later.
-
-`integer, intent(out) :: ierr` is optional.
-It will be non-zero if error detected.
-This value should be checked, particularly for write operations to avoid missing error conditions.
-If `ierr` is omitted, nc4fortran will `error stop` on error.
-
-### Create new NetCDF file, with variable "value1"
-
-```fortran
-call hf%open('test.nc', action='w')
-
-call hf%write('value1', 123.)
-
-call hf%close()
-```
-
-### Check if variable exists
-
-This will not raise error stop, even if the file isn't opened, but it will print a message to stderr.
-
-```fortran
-logical :: exists
-
-exists = hf%exist('fooname')
-```
-
-### Add/append variable "value1" to existing NetCDF file "test.nc"
-
-* if file `test.nc` exists, add a variable to it
-* if file `test.nc` does not exist, create it and add a variable to it.
-
-```fortran
-call hf%open('test.nc', action='rw')
-
-call hf%write('value1', 123.)
-
-call hf%close()
-```
-
-### Read scalar, 3-D array of unknown size
-
-```fortran
-call ncf%open('test.nc', action='r')
-
-integer, allocatable :: dims(:)
-real, allocatable :: A(:,:,:)
-
-call ncf%shape('foo', dims)
-allocate(A(dims(1), dims(2), dims(3)))
-call ncf%read('foo', A)
-
-call ncf%close()
+revision = v1.5.0
 ```
 
 ## Permissive syntax

src/interface.f90

@@ -12,7 +12,7 @@ module nc4fortran
 
 implicit none (type, external)
 private
-public :: netcdf_file, NF90_MAX_NAME, NF90_NOERR, check_error, is_netcdf, nc_exist
+public :: netcdf_file, NF90_MAX_NAME, NF90_NOERR, check_error, is_netcdf, nc_exist, nc4version
 
 !! at this time, we assume up to 7 dimension NetCDF variable.
 integer, parameter :: NC_MAXDIM = 7
@@ -28,7 +28,6 @@ module nc4fortran
 logical :: debug = .false.
 logical :: is_open = .false.
 !! will be auto-deleted on close
-character(80) :: libversion
 
 contains
 
@@ -240,9 +239,6 @@ subroutine nc_initialize(self, filename, action, comp_lvl, verbose, debug)
 if (present(verbose)) self%verbose = verbose
 if (present(debug)) self%debug = debug
 
-!> get library version
-self%libversion = nf90_inq_libvers()
-
 laction = 'rw'
 if(present(action)) laction = action
 
@@ -307,6 +303,13 @@ subroutine nc_finalize(self)
 end subroutine nc_finalize
 
 
+function nc4version()
+!! get NetCDF4 library version
+character(:), allocatable :: nc4version
+nc4version = nf90_inq_libvers()
+end function nc4version
+
+
 subroutine nc_flush(self)
 
 class(netcdf_file), intent(in) :: self

src/tests/CMakeLists.txt

@@ -11,19 +11,22 @@ FIXTURES_SETUP nclib
 LABELS core
 )
 
-foreach(t array attributes deflate destructor error exist scalar shape string)
+foreach(t array attributes deflate destructor error exist scalar shape string version)
   add_executable(test_${t} test_${t}.f90)
   target_link_libraries(test_${t} PRIVATE nc4fortran::nc4fortran)
   set_target_properties(test_${t} PROPERTIES LABELS unit)
   target_compile_options(test_${t} PRIVATE "$<$<Fortran_COMPILER_ID:GNU>:-Wno-compare-reals>")
 
-  add_test(NAME ${t}
-  COMMAND test_${t}
-  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
-  )
+  if(${t} STREQUAL version)
+    add_test(NAME ${t} COMMAND test_${t} ${NetCDF_VERSION})
+  else()
+    add_test(NAME ${t} COMMAND test_${t})
+  endif()
+
   set_tests_properties(${t} PROPERTIES
   FIXTURES_REQUIRED nclib
   LABELS unit
+  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
   )
 endforeach()
 

src/tests/meson.build

@@ -6,7 +6,7 @@ test('minimal', test_minimal,
   priority: 100,
   timeout: 10)
 
-foreach t : ['array', 'attributes', 'deflate', 'destructor', 'error', 'exist', 'scalar', 'shape', 'string']
+foreach t : ['array', 'attributes', 'deflate', 'destructor', 'error', 'exist', 'scalar', 'shape', 'string', 'version']
 
   e = executable('test_'+t, 'test_' + t + '.f90', dependencies: netcdf_interface, fortran_args: quiet)
   if t == 'shape'

src/tests/test_version.f90

@@ -0,0 +1,49 @@
+program test_version
+!! tests that NetCDF4 library version is available
+
+use nc4fortran, only : nc4version
+
+implicit none (type, external)
+
+character(24) :: vstr, v
+character(:), allocatable :: libver, compver
+integer :: i
+
+v = nc4version()
+
+print '(A)', v
+
+if(command_argument_count() < 1) stop
+
+call get_command_argument(1, vstr, status=i)
+if (i/=0) error stop "input version string to compare"
+
+compver = get_version_mmr(vstr)
+libver = get_version_mmr(v)
+if (compver /= libver) error stop "version mismatch: " // compver // " /= " // libver
+
+contains
+
+pure function get_version_mmr(v)
+!! get the major.minor.release part of a version string
+!! cuts off further patch and arbitrary text
+character(:), allocatable :: get_version_mmr
+character(*), intent(in) :: v
+
+integer :: i, j, k, e
+
+k = index(v, '.')
+j = index(v(k+1:), '.')
+i = scan(v(k+j+1:), '.-_ ')
+if (i == 0) then
+  e = len_trim(v)
+else
+  e = k + j + i - 1
+end if
+
+get_version_mmr = v(:e)
+
+end function get_version_mmr
+
+
+end program