Plot Elliptic Curve by gnuplot.

This program requires gnuplot to be installed.

It opens gnuplot and sends command to plot EC whenever user orders to do so.

To install gnuplot in Linux:

apt-get install gnuplot

Another requirements.

Program includes programming library called ncurses which provides terminal API, to install it type e.g.:

apt-get install libncurses5-dev

Usage

Presents equation y^2 = x^3 + a x + b where one can change parameters:

EC: y^2 = x^3 - 43*x + 114

Presents x value(s) for point(s) where y = 0 (also on the head of graph):

  x for y = 0: -7.613966

Computes the value of discriminant parameter for Elliptic Curves:

  4*a^3 + 27*b^2 = 32864.0  (-43, 114)

When > 0 then there is only one point for y = 0 and function can be used for Elliptic Curve Cryptography.

When = 0 then there are 2 points for y = 0

When < 0 then it has 3 points for y = 0 and graph has 2 separated parts like on the image below:

Press enter to plot the equation:

 Plot EC

Press enter to exit

 Exit

TODOs

Changing number of points and their precision. Stepping on points to e.g. show their coordinates and plot the tangent line (optional).