docs: Cleanup and update some docs.

1 files changed, 37 insertions, 5 deletions

diff --git a/docs/library/math.rst b/docs/library/math.rst
index 53427ea557..988a8c2843 100644
--- a/docs/library/math.rst
+++ b/docs/library/math.rst
@@ -1,5 +1,5 @@
-:mod:`math` --- mathematical functions
-======================================
+:mod:`math` -- mathematical functions
+=====================================
 
 .. module:: math
    :synopsis: mathematical functions
@@ -7,45 +7,58 @@
 The ``math`` module provides some basic mathematical funtions for
 working with floating-point numbers.
 
+*Note:* On the pyboard, floating-point numbers have 32-bit precision.
 
 Functions
 ---------
 
 .. function:: acos(x)
 
+   Return the inverse cosine of ``x``.
 
 .. function:: acosh(x)
 
+   Return the inverse hyperbolic cosine of ``x``.
 
 .. function:: asin(x)
 
+   Return the inverse sine of ``x``.
 
 .. function:: asinh(x)
 
+   Return the inverse hyperbolic sine of ``x``.
 
 .. function:: atan(x)
 
+   Return the inverse tangent of ``x``.
 
 .. function:: atan2(y, x)
 
+   Return the principal value of the inverse tangent of ``y/x``.
 
 .. function:: atanh(x)
 
+   Return the inverse hyperbolic tangent of ``x``.
 
 .. function:: ceil(x)
 
+   Return an integer, being ``x`` rounded towards positive infinity.
 
 .. function:: copysign(x, y)
 
+   Return ``x`` with the sign of ``y``.
 
 .. function:: cos(x)
 
+   Return the cosine of ``x``.
 
 .. function:: cosh(x)
 
+   Return the hyperbolic cosine of ``x``.
 
 .. function:: degrees(x)
 
+   Return radians ``x`` converted to degrees.
 
 .. function:: erf(x)
 
@@ -57,18 +70,23 @@ Functions
 
 .. function:: exp(x)
 
+   Return the exponential of ``x``.
 
 .. function:: expm1(x)
 
+   Return ``exp(x) - 1``.
 
 .. function:: fabs(x)
 
+   Return the absolute value of ``x``.
 
 .. function:: floor(x)
 
+   Return an integer, being ``x`` rounded towards negative infinity.
 
 .. function:: fmod(x, y)
 
+   Return the remainder of ``x/y``.
 
 .. function:: frexp(x)
 
@@ -80,31 +98,40 @@ Functions
 
 .. function:: isfinite(x)
 
+   Return ``True`` if ``x`` is finite.
 
 .. function:: isinf(x)
 
+   Return ``True`` if ``x`` is infinite.
 
 .. function:: isnan(x)
 
+   Return ``True`` if ``x`` is not-a-number
 
 .. function:: ldexp(x, exp)
 
+   Return ``x * (2**exp)``.
 
 .. function:: lgamma(x)
 
-   return the natural logarithm of the gamma function of ``x``.
+   Return the natural logarithm of the gamma function of ``x``.
 
 .. function:: log(x)
 
+   Return the natural logarithm of ``x``.
 
 .. function:: log10(x)
 
+   Return the base-10 logarithm of ``x``.
 
 .. function:: log2(x)
 
+   Return the base-2 logarithm of ``x``.
 
 .. function:: modf(x)
 
+   Return a tuple of two floats, being the fractional and integral parts of
+   ``x``.  Both return values have the same sign as ``x``.
 
 .. function:: pow(x, y)
 
@@ -112,26 +139,31 @@ Functions
 
 .. function:: radians(x)
 
+   Return degrees ``x`` converted to radians.
 
 .. function:: sin(x)
 
+   Return the sine of ``x``.
 
 .. function:: sinh(x)
 
+   Return the hyperbolic sine of ``x``.
 
 .. function:: sqrt(x)
 
-   Returns the square root of ``x``.
+   Return the square root of ``x``.
 
 .. function:: tan(x)
 
+   Return the tangent of ``x``.
 
 .. function:: tanh(x)
 
+   Return the hyperbolic tangent of ``x``.
 
 .. function:: trunc(x)
 
-
+   Return an integer, being ``x`` rounded towards 0.
 
 Constants
 ---------