add h5exist() convenient method

Author: scivision

CMakeLists.txt

@@ -4,7 +4,7 @@ if(NOT CMAKE_BUILD_TYPE)
 endif()
 project(h5fortran
   LANGUAGES C Fortran
-  VERSION 2.9.2
+  VERSION 2.9.3
   DESCRIPTION "thin, light object-oriented HDF5 Fortran interface"
   HOMEPAGE_URL https://github.com/scivision/h5fortran)
 enable_testing()

Examples.md

@@ -59,10 +59,16 @@ Currently, data is written contiguous if not compressed and is only chunked if c
 
 ## check if a variable exists
 
-the logical method %exists() checks if a dataset (variable) exists in the initialized HDF5 file.
+the logical method %exist() checks if a dataset (variable) exists in the initialized HDF5 file.
 
 ```fortran
-exists = h5f%exists("/foo")
+exists = h5f%exist("/foo")
+```
+
+A convenience method that checks existance of a dataset without creating the h5 object manually is:
+
+```fortran
+exists = h5exist("my.h5", "/foo")
 ```
 
 ## Read scalar, 3-D array of unknown size

src/interface.f90

@@ -19,7 +19,7 @@ module h5fortran
 implicit none (type, external)
 private
 public :: hdf5_file, toLower, hdf_shape_check, hdf_get_slice, hdf_wrapup, hsize_t, strip_trailing_null, truncate_string_null, &
-  check, h5write, h5read
+  check, h5write, h5read, h5exist
 
 !> Workaround for Intel 19.1 / 2020 bug with /stand:f18
 !> error #6410: This name has not been declared as an array or a function.   [RANK]
@@ -75,6 +75,11 @@ module h5fortran
 !> Submodules
 interface
 
+module logical function h5exist(filename, dname)
+character(*), intent(in) :: filename, dname
+end function h5exist
+
+
 module subroutine lt0write(filename, dname, value, ierr)
 character(*), intent(in) :: filename, dname
 class(*), intent(in) :: value

src/reader_lt.f90

@@ -4,11 +4,22 @@
 
 contains
 
+module procedure h5exist
+
+type(hdf5_file) :: h
+
+call h%initialize(filename, status='old', action='r')
+h5exist = h%exist(dname)
+call h%finalize()
+
+end procedure h5exist
+
+
 module procedure lt0read
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -41,7 +52,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -72,7 +83,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -103,7 +114,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -134,7 +145,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -165,7 +176,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -196,7 +207,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -227,7 +238,7 @@
 type(hdf5_file) :: h
 integer :: ier
 
-call h%initialize(filename, ier, status='old')
+call h%initialize(filename, ier, status='old', action='r')
 
 if (ier == 0) then
 select type (value)
@@ -253,4 +264,4 @@
 
 end procedure lt7read
 
-end submodule reader_lt
+end submodule reader_lt

src/tests/test_exist.f90

@@ -1,7 +1,7 @@
 program test_exist
 !! test "exist" variable
 use, intrinsic :: iso_fortran_env, only : stderr=>error_unit
-use h5fortran, only: hdf5_file, h5write
+use h5fortran, only: hdf5_file, h5write, h5exist
 
 implicit none (type, external)
 
@@ -25,4 +25,9 @@ program test_exist
 
 if (h%exist('/foo')) error stop 'foo not exist'
 
+call h%finalize()
+
+if (.not. h5exist(path, '/x')) error stop 'x exists'
+if (h5exist(path, '/foo')) error stop 'foo not exist'
+
 end program

src/tests/test_lt.f90

@@ -6,6 +6,7 @@ module test_lt
 
 contains
 
+
 subroutine test_readwrite_lt(path)
 
 character(*), intent(in) :: path