1 files changed, 29 insertions, 0 deletions
diff --git a/frob_norm.py b/frob_norm.py
new file mode 100644
index 000000000..8f8dc48bd
--- /dev/null
+++ b/frob_norm.py
@@ -0,0 +1,29 @@
+import math
+
+
+def frob_norm(array):
+    """
+    Calculates the frobenius norm of a given array or matrix.
+    array: array of data.
+    """
+
+    arr_sh_len = len(array.shape)
+    arr_range = range(len(array))
+    fn = 0.0
+
+    # If it is a 'vector'.
+    if arr_sh_len == 1:
+        for i in arr_range:
+            fn += array[i]*array[i]
+
+        return math.sqrt(fn)
+
+    # If it is a matrix.
+    elif arr_sh_len == 2:
+        for i in arr_range:
+            for j in arr_range:
+                fn += array[i, j]*array[i, j]
+
+        return math.sqrt(fn)
+    else:
+        print('Error. Array size greater than 2 ({}).'.format(arr_sh_len))