Drawing the surface of the binary function f(r, a) with polar coordinates online

This page draws the shape and surface of the binary function f(r, a) expressed in polar coordinates, where
r is the amplitude mode and a is the angle of the xy plane. In the following input boxes, the definition of
the binary function f(r, a) is input in a high-level language-like expression. For example, the rotation paraboloid
is \(r^2\) or \(r*r\), and some commonly used functions are also supported. See the input method
Constant expression calculation page and binary function value calculation
page, but the arguments can only be represented by the letters r and a. Never use x, y. You must also enter
the image range of the surface, r1, r2 is the drawing range of the modulo, t1 < t2, a1, a2 is the drawing range
of the angle a, a1 < a2, these four numbers can be input with a constant expression, for example, \((2*p)^{\frac{1}{2}} \)
represents the square of the pi of 2 times, and so on. For the input syntax of constant expressions, see "
Constant Expression" page, enter the individual data and click the "Start Drawing" button,
the surface of the function will be displayed.