Code review

- NX_FLOAT -> NX_NUMBER for scaling_factor and offset
- Sync language with number #1396 for the FIELDNAME convention

base_classes/NXdata.nxdl.xml

@@ -446,9 +446,12 @@
 	</field>
 
 	<!-- Data vs. plot coordinates -->
-	<field name="FIELDNAME_scaling_factor" type="NX_FLOAT">
+	<field name="FIELDNAME_scaling_factor" type="NX_NUMBER">
 		<doc>
-			An optional scaling factor to apply to the values in FIELDNAME (usually the signal).
+			An optional scaling factor to apply to the values in any field named ``FIELDNAME``
+			in this ``NXdata`` group. This can be a :ref:`DATA &lt;/NXdata/DATA-field&gt;` field
+			(signal or auxiliary signal) or a :ref:`AXISNAME &lt;/NXdata/AXISNAME-field&gt;`
+			field (axis).
 
 			The elements stored in NXdata datasets are often stored as integers for efficiency
 			reasons and need further correction or conversion, generating floats.  For example,
@@ -463,7 +466,7 @@
 			This formula will derive the values to use in downstream applications, when necessary.
 		</doc>
 	</field>
-	<field name="FIELDNAME_offset" type="NX_FLOAT">
+	<field name="FIELDNAME_offset" type="NX_NUMBER">
 		<doc>
 			An optional offset to apply to the values in FIELDNAME (usually the signal).