Add mem:// backend example (#1904)

* Add mem:// backend example
* check the URI before creating the array

Author: kounelisagis

examples/in_memory_vfs.py

@@ -0,0 +1,50 @@
+# in_memory_vfs.py
+#
+# LICENSE
+#
+# The MIT License
+#
+# Copyright (c) 2024 TileDB, Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# DESCRIPTION
+#
+# When run, this program will create a random numpy array, create a TileDB
+# DenseArray from it in memory, and read the entire array back from memory.
+# It then compares the original numpy array with the TileDB array to check
+# that data was written and read correctly (prints True) or not (prints False).
+#
+
+import numpy as np
+
+import tiledb
+
+# Create TileDB VFS
+vfs = tiledb.VFS()
+
+file = "mem://myarray"
+data = np.random.rand(10, 10)
+
+if not vfs.is_file(file):
+    with tiledb.from_numpy(file, data):
+        pass
+
+with tiledb.open(file) as A:
+    print(np.all(A[:] == data))