Add a single table as summary to cmath documentation

Doc/library/cmath.rst

@@ -38,6 +38,57 @@ the function is then applied to the result of the conversion.
  1.4142135623730951j
 
 
+==================================================== ============================================
+**Conversions to and from polar coordinates**
+--------------------------------------------------------------------------------------------------
+:func:`phase(z) <phase>` Return the phase of *z*
+:func:`polar(z) <polar>` Return the representation of *z* in polar coordinates
+:func:`rect(r, phi) <rect>` Return the complex number *z* with polar coordinates *r* and *phi*
+
+**Power and logarithmic functions**
+--------------------------------------------------------------------------------------------------
+:func:`exp(z) <exp>` Return *e* raised to the power *z*
+:func:`log(z[, base]) <log>` Return the logarithm of *z* to the given *base* (*e* by default)
+:func:`log10(z) <log10>` Return the base-10 logarithm of *z*
+:func:`sqrt(z) <sqrt>` Return the square root of *z*
+
+**Trigonometric functions**
+--------------------------------------------------------------------------------------------------
+:func:`acos(z) <acos>` Return the arc cosine of *z*
+:func:`asin(z) <asin>` Return the arc sine of *z*
+:func:`atan(z) <atan>` Return the arc tangent of *z*
+:func:`cos(z) <cos>` Return the cosine of *z*
+:func:`sin(z) <sin>` Return the sine of *z*
+:func:`tan(z) <tan>` Return the tangent of *z*
+
+**Hyperbolic functions**
+--------------------------------------------------------------------------------------------------
+:func:`acosh(z) <acosh>` Return the inverse hyperbolic cosine of *z*
+:func:`asinh(z) <asinh>` Return the inverse hyperbolic sine of *z*
+:func:`atanh(z) <atanh>` Return the inverse hyperbolic tangent of *z*
+:func:`cosh(z) <cosh>` Return the hyperbolic cosine of *z*
+:func:`sinh(z) <sinh>` Return the hyperbolic sine of *z*
+:func:`tanh(z) <tanh>` Return the hyperbolic tangent of *z*
+
+**Classification functions**
+--------------------------------------------------------------------------------------------------
+:func:`isfinite(z) <isfinite>` Check if all components of *z* are finite
+:func:`isinf(z) <isinf>` Check if any component of *z* is infinite
+:func:`isnan(z) <isnan>` Check if any component of *z* is a NaN
+:func:`isclose(a, b, *, rel_tol, abs_tol) <isclose>` Check if the values *a* and *b* are close to each other
+
+**Constants**
+--------------------------------------------------------------------------------------------------
+:data:`pi` *π* = 3.141592...
+:data:`e` *e* = 2.718281...
+:data:`tau` *τ* = 2\ *π* = 6.283185...
+:data:`inf` Positive infinity
+:data:`infj` Pure imaginary infinity
+:data:`nan` "Not a number" (NaN)
+:data:`nanj` Pure imaginary NaN
+==================================================== ============================================
+
+
 Conversions to and from polar coordinates
 -----------------------------------------