Ticket #14403: 14403_decimalFloat.diff

docs/ref/models/fields.txt

@@ -454 +454 @@
 
 The admin represents this as an ``<input type="text">`` (a single-line input).
 
+.. note:: Information about difference between :class:`FloatField` and
+   :class:`DecimalField` types can be found in `FloatField and DecimalField`_.
+
 ``EmailField``
 --------------
 
@@ -665 +668 @@
 
 The admin represents this as an ``<input type="text">`` (a single-line input).
 
+FloatField and DecimalField
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+:class:`FloatField` type is sometimes mixed up with :class:`DecimalField` type.
+Although they both represent real numbers, they have different representation
+systems. Float uses `floating point number representation system`_, and decimal
+(sometimes called *numeric* or *fixed point number*) uses `fixed point number
+representation system`_. For both field types there is corresponding type in
+`databases numeric types`_ and `python numeric types`_.
+
+.. _floating number representation system: http://en.wikipedia.org/wiki/Floating_point 
+.. _fixed point number representation system: http://en.wikipedia.org/wiki/Fixed-point_arithmetic 
+.. _databases numeric types: http://en.wikipedia.org/wiki/SQL#Numbers
+.. _python numeric types: http://docs.python.org/library/decimal.html
+
+
 ``ImageField``
 --------------