Update README.md

Added encode/decode example methods in Java and Python

Author: lior-k

README.md

@@ -43,6 +43,47 @@ give it a try.
 ```
 * The vector can be of any dimension
 
+### Converting a vector to Base64
+to convert an array of doubles to a base64 string we use these example methods:
+
+**Java**
+```
+public static final String convertArrayToBase64(double[] array) {
+		final int capacity = 8 * array.length;
+		final ByteBuffer bb = ByteBuffer.allocate(capacity);
+		for (int i = 0; i < array.length; i++) {
+			bb.putDouble(array[i]);
+		}
+		bb.rewind();
+		final ByteBuffer encodedBB = Base64.getEncoder().encode(bb);
+		return new String(encodedBB.array());
+	}
+
+	public static double[] convertBase64ToArray(String base64Str) {
+		final byte[] decode = Base64.getDecoder().decode(base64Str.getBytes());
+		final DoubleBuffer doubleBuffer = ByteBuffer.wrap(decode).asDoubleBuffer();
+
+		final double[] dims = new double[doubleBuffer.capacity()];
+		doubleBuffer.get(dims);
+		return dims;
+	}
+```
+**Python**
+```
+import base64
+import numpy as np
+
+dbig = np.dtype('>f8')
+
+def decode_float_list(base64_string):
+    bytes = base64.b64decode(base64_string)
+    return np.frombuffer(bytes, dtype=dbig).tolist()
+
+def encode_array(arr):
+    base64_str = base64.b64encode(np.array(arr).astype(dbig)).decode("utf-8")
+    return base64_str
+```
+
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