Document Float Math functions

content/en/docs/chart_template_guide/function_list.md

@@ -16,6 +16,7 @@ They are listed here and broken down by the following categories:
 * [Logic and Flow Control](#logic-and-flow-control-functions)
 * [Lists](#lists-and-list-functions)
 * [Math](#math-functions)
+* [Float Math](#float-math-functions)
 * [Network](#network-functions)
 * [Reflection](#reflection-functions)
 * [Regular Expressions](#regular-expressions)
@@ -1784,6 +1785,82 @@ Return the smallest of a series of integers.
 
 `min 1 2 3` will return `1`.
 
+### len
+
+Returns the length of the argument as an integer.
+
+```
+len .Arg
+```
+
+## Float Math Functions
+
+All math functions operate on `float64` values.
+
+### addf
+
+Sum numbers with `addf`
+
+This will return `5.5`:
+
+```
+addf 1.5 2 2
+```
+
+### add1f
+
+To increment by 1, use `add1f`
+
+### subf
+
+To subtract, use `subf`
+
+This is equivalent to `7.5 - 2 - 3` and will return `2.5`:
+
+```
+subf 7.5 2 3
+```
+
+### divf
+
+Perform integer division with `divf`
+
+This is equivalent to `10 / 2 / 4` and will return `1.25`:
+
+```
+divf 10 2 4
+```
+
+### mulf
+
+Multiply with `mulf`
+
+This will return `6`:
+
+```
+mulf 1.5 2 2
+```
+
+### maxf
+
+Return the largest of a series of floats:
+
+This will return `3`:
+
+```
+maxf 1 2.5 3
+```
+
+### minf
+
+Return the smallest of a series of floats.
+
+This will return `1.5`:
+
+```
+minf 1.5 2 3
+```
+
 ### floor
 
 Returns the greatest float value less than or equal to input value.
@@ -1803,14 +1880,6 @@ after the decimal point.
 
 `round 123.555555 3` will return `123.556`.
 
-### len
-
-Returns the length of the argument as an integer.
-
-```
-len .Arg
-```
-
 ## Network Functions
 
 Helm has a single network function, `getHostByName`.