From 3137063d22af526e6ab036779b788f9a241b18ba Mon Sep 17 00:00:00 2001
From: Achim Gsell <achim.gsell@psi.ch>
Date: Fri, 8 Apr 2016 19:06:42 +0200
Subject: [PATCH] example/H5Block: - has_field.c added

---
 examples/H5Block/Makefile.am |  6 ++-
 examples/H5Block/has_field.c | 82 ++++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+), 2 deletions(-)
 create mode 100644 examples/H5Block/has_field.c

diff --git a/examples/H5Block/Makefile.am b/examples/H5Block/Makefile.am
index b739d7d..4291150 100644
--- a/examples/H5Block/Makefile.am
+++ b/examples/H5Block/Makefile.am
@@ -24,8 +24,9 @@ LDADD += -lH5hut
 noinst_PROGRAMS = 
 
 if ENABLE_C
-noinst_PROGRAMS += 	\
-	fields		\
+noinst_PROGRAMS +=		\
+	fields			\
+	has_field		\
 	read_write_scalar_field \
 	write_field
 endif
@@ -37,6 +38,7 @@ endif
 endif
 
 fields_SOURCES = fields.c
+has_field_SOURCES = has_field.c
 read_write_scalar_field_SOURCES = read_write_scalar_field.c
 read_write_scalar_fieldf_SOURCES = read_write_scalar_fieldf.f90
 write_field_SOURCES = write_field.c
diff --git a/examples/H5Block/has_field.c b/examples/H5Block/has_field.c
new file mode 100644
index 0000000..90f5179
--- /dev/null
+++ b/examples/H5Block/has_field.c
@@ -0,0 +1,82 @@
+/*
+  Copyright (c) 2006-2015, The Regents of the University of California,
+  through Lawrence Berkeley National Laboratory (subject to receipt of any
+  required approvals from the U.S. Dept. of Energy) and the Paul Scherrer
+  Institut (Switzerland).  All rights reserved.
+
+  License: see file COPYING in top level of source distribution.
+*/
+
+#include "H5hut.h"
+
+// name of output file
+const char* fname = "example_write_field.h5";
+
+// H5hut verbosity level
+const h5_int64_t h5_verbosity = H5_VERBOSE_DEFAULT;
+
+int
+main (
+        int argc,
+        char* argv[]
+        ){
+
+        // initialize MPI & H5hut
+        MPI_Init (&argc, &argv);
+        MPI_Comm comm = MPI_COMM_WORLD;
+        int comm_size = 1;
+        MPI_Comm_size (comm, &comm_size);
+	int comm_rank = 0;
+        MPI_Comm_rank (comm, &comm_rank);
+        H5AbortOnError ();
+        H5SetVerbosityLevel (h5_verbosity);
+	//H5SetDebugMask (-1);
+
+        // open file and create first step
+        h5_file_t file = H5OpenFile (fname, H5_O_RDONLY, H5_PROP_DEFAULT);
+        H5SetStep (file, 0); 
+
+	if (!H5BlockHasFieldData (file)) {
+		goto done;
+	}
+	printf ("Has field data in step#0\n");
+
+	if (!H5BlockHasField (file, "data")) {
+		goto done;
+	}
+	printf ("Has field data with name 'data' in step#0\n");
+
+	h5_size_t field_rank;
+	h5_size_t field_dims[3];
+	h5_size_t elem_rank;
+	h5_int64_t type;
+	H5BlockGetFieldInfoByName (
+		file,
+		"data",
+		&field_rank,
+		field_dims,
+		&elem_rank,
+		&type);
+	char* stype = "unknown";
+	if (type == H5_INT64_T) {
+		stype = "H5_INT64_T";
+	} else if (type == H5_INT32_T) {
+		stype = "H5_INT32_T";
+	} else if (type == H5_FLOAT64_T) {
+		stype = "H5_FLOAT64_T";
+	} else if (type == H5_FLOAT32_T) {
+		stype = "H5_FLOAT32_T";
+	} else if (type == H5_STRING_T) {
+		stype = "H5_STRING_T";
+	}
+	printf ("rank of field:       %lld\n", field_rank);
+	printf ("dims of field:      [%lld, %lld, %lld]\n",
+		field_dims[0], field_dims[1], field_dims[2]);
+	printf ("rank of field data: %lld\n", elem_rank);
+	printf ("type of field data: '%s'\n", stype);
+done:
+        // done
+        H5CloseFile(file);
+	MPI_Finalize ();
+        return 0;
+}