diff --git a/doc/python/source/rsgislib_tools.rst b/doc/python/source/rsgislib_tools.rst
index 03e92fab..e2334cde 100644
--- a/doc/python/source/rsgislib_tools.rst
+++ b/doc/python/source/rsgislib_tools.rst
@@ -11,6 +11,7 @@ RSGISLib Tools
    rsgislib_tools_projection
    rsgislib_tools_plotting
    rsgislib_tools_stats
+   rsgislib_tools_maths
    rsgislib_tools_imagetools
    rsgislib_tools_sensors
    rsgislib_tools_sysprofile
diff --git a/doc/python/source/rsgislib_tools_maths.rst b/doc/python/source/rsgislib_tools_maths.rst
new file mode 100644
index 00000000..cf08ab3e
--- /dev/null
+++ b/doc/python/source/rsgislib_tools_maths.rst
@@ -0,0 +1,12 @@
+RSGISLib Maths Tools
+=============================
+
+Normalisation
+----------------
+.. autofunction:: rsgislib.tools.maths.round_to_nearest_val
+
+
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`
diff --git a/python/rsgislib/__init__.py b/python/rsgislib/__init__.py
index 3460020a..2debabd2 100644
--- a/python/rsgislib/__init__.py
+++ b/python/rsgislib/__init__.py
@@ -163,6 +163,12 @@
     * VAR_TYPE_CONTINUOUS = 1
     * VAR_TYPE_CATEGORICAL = 2
 
+
+Options for rounding numbers:
+    * ROUND_NEAREST = 1
+    * ROUND_UP = 2
+    * ROUND_DOWN = 3
+
 """
 from __future__ import print_function
 
@@ -301,6 +307,10 @@
 VAR_TYPE_CONTINUOUS = 1
 VAR_TYPE_CATEGORICAL = 2
 
+ROUND_NEAREST = 1
+ROUND_UP = 2
+ROUND_DOWN = 3
+
 
 def get_install_base_path() -> pathlib.PurePath:
     """
diff --git a/python/rsgislib/tools/ftptools.py b/python/rsgislib/tools/ftptools.py
index 683896bd..ca95bc7d 100644
--- a/python/rsgislib/tools/ftptools.py
+++ b/python/rsgislib/tools/ftptools.py
@@ -417,12 +417,13 @@ def download_curl_ftp_file(
                 )
             )
         success = True
-    except:
+    except pycurl.error as e:
         print(
             "An error occurred when downloading {}.".format(
                 os.path.join(ftp_url, remote_file)
             )
         )
+        print(e)
         success = False
     return success
 
diff --git a/python/rsgislib/tools/mapping.py b/python/rsgislib/tools/mapping.py
index 56d76f79..013bef03 100644
--- a/python/rsgislib/tools/mapping.py
+++ b/python/rsgislib/tools/mapping.py
@@ -698,19 +698,29 @@ def create_raster_img_map(
                 "Manual stretch requires user parameters to be passed"
             )
         img_data_strch = rsgislib.tools.plotting.manual_stretch_np_arr(
-            img_data, min_max_vals=stch_min_max_vals, no_data_val=img_no_data_val, no_data_clr=no_data_out_clr,
+            img_data,
+            min_max_vals=stch_min_max_vals,
+            no_data_val=img_no_data_val,
+            no_data_clr=no_data_out_clr,
         )
     elif img_stch == rsgislib.IMG_STRETCH_LINEAR:
         img_data_strch = rsgislib.tools.plotting.linear_stretch_np_arr(
-            img_data, no_data_val=img_no_data_val, no_data_clr=no_data_out_clr,
+            img_data,
+            no_data_val=img_no_data_val,
+            no_data_clr=no_data_out_clr,
         )
     elif img_stch == rsgislib.IMG_STRETCH_STDEV:
         img_data_strch = rsgislib.tools.plotting.stdev_stretch_np_arr(
-            img_data, n_stdevs=stch_n_stdevs, no_data_val=img_no_data_val, no_data_clr=no_data_out_clr,
+            img_data,
+            n_stdevs=stch_n_stdevs,
+            no_data_val=img_no_data_val,
+            no_data_clr=no_data_out_clr,
         )
     elif img_stch == rsgislib.IMG_STRETCH_CUMULATIVE:
         img_data_strch = rsgislib.tools.plotting.cumulative_stretch_np_arr(
-            img_data, no_data_val=img_no_data_val, no_data_clr=no_data_out_clr,
+            img_data,
+            no_data_val=img_no_data_val,
+            no_data_clr=no_data_out_clr,
         )
     else:
         print("No stretch is being used - is this what you intended?!")
diff --git a/python/rsgislib/tools/maths.py b/python/rsgislib/tools/maths.py
new file mode 100644
index 00000000..c700a151
--- /dev/null
+++ b/python/rsgislib/tools/maths.py
@@ -0,0 +1,47 @@
+#!/usr/bin/env python
+"""
+The tools.maths module contains some useful tools for maths operations which aren't
+easily available else where.
+
+"""
+from typing import Union, List
+
+import numpy
+
+import rsgislib
+
+
+def round_to_nearest_val(
+    input_val: Union[numpy.array, int, float, List[int], List[float]],
+    round_val: int = 1,
+    round_direction: int = rsgislib.ROUND_NEAREST,
+):
+    """
+    Rounds elements of a NumPy array to the nearest multiple of the value specified,
+    with options for rounding up, down or to the nearest value. For example, if a
+    round_val of 5 is provided then the numbers will be rounded to intervals of 5.
+
+    :param input_val: A NumPy array of numbers.
+    :param round_val: The value by which the input is to be rounded to.
+    :param round_direction: Specify the round direction (rsgislib.ROUND_NEAREST,
+                            rsgislib.ROUND_UP, or rsgislib.ROUND_DOWN). The
+                            default is rsgislib.ROUND_NEAREST.
+    :return: a single value or a numpy array of the rounded values.
+
+    """
+    if isinstance(input_val, list):
+        input_val = numpy.array(input_val, dtype=float)
+
+    round_val_flt = float(round_val)
+    round_val_int = int(round_val)
+    if round_direction == rsgislib.ROUND_NEAREST:
+        return numpy.round(input_val / round_val_flt) * round_val_int
+    elif round_direction == rsgislib.ROUND_UP:
+        return numpy.ceil(input_val / round_val_flt) * round_val_int
+    elif round_direction == rsgislib.ROUND_DOWN:
+        return numpy.floor(input_val / round_val_flt) * round_val_int
+    else:
+        raise rsgislib.RSGISPyException(
+            f"Invalid round_direction: '{round_direction}'. Please use "
+            f"rsgislib.ROUND_NEAREST, rsgislib.ROUND_UP, or rsgislib.ROUND_DOWN."
+        )
diff --git a/python/rsgislib/tools/plotting.py b/python/rsgislib/tools/plotting.py
index 5c8f9986..97126f86 100644
--- a/python/rsgislib/tools/plotting.py
+++ b/python/rsgislib/tools/plotting.py
@@ -1044,7 +1044,7 @@ def linear_stretch_np_arr(
     out_int_type: bool = False,
     min_out_val: float = 0,
     max_out_val: float = 1,
-    no_data_clr:Tuple[float, float, float] = None,
+    no_data_clr: Tuple[float, float, float] = None,
 ) -> numpy.array:
     """
     A function which performs a linear stretch using the min-max values on a per
@@ -1145,7 +1145,7 @@ def cumulative_stretch_np_arr(
     out_int_type: bool = False,
     min_out_val: float = 0,
     max_out_val: float = 1,
-    no_data_clr:Tuple[float, float, float] = None,
+    no_data_clr: Tuple[float, float, float] = None,
 ) -> numpy.array:
     """
     A function which performs a cumulative stretch using an upper and lower
@@ -1245,7 +1245,7 @@ def stdev_stretch_np_arr(
     out_int_type: bool = False,
     min_out_val: float = 0,
     max_out_val: float = 1,
-    no_data_clr:Tuple[float, float, float] = None,
+    no_data_clr: Tuple[float, float, float] = None,
 ) -> numpy.array:
     """
     A function which performs a standard deviation stretch using an upper and lower
@@ -1369,7 +1369,7 @@ def manual_stretch_np_arr(
     out_int_type: bool = False,
     min_out_val: float = 0,
     max_out_val: float = 1,
-    no_data_clr:Tuple[float, float, float] = None,
+    no_data_clr: Tuple[float, float, float] = None,
 ) -> numpy.array:
     """
     A function which performs a linear stretch using the min-max values provided
diff --git a/python/rsgislib/tools/stats.py b/python/rsgislib/tools/stats.py
index 17eafa17..93335545 100644
--- a/python/rsgislib/tools/stats.py
+++ b/python/rsgislib/tools/stats.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python
 """
-The tools.stats module contains some useful tools for calculating useful statistics which aren't
-easily available else where.
+The tools.stats module contains some useful tools for calculating useful statistics
+which aren't easily available else where.
 """
 from typing import Union, List