Quadratic Spline Interpolation with first linear spline is provided by this code.
In the first two lines the user has to insert data points (x), (y) and then execute the program.
The output of this code is the coefficients of quadratic equation in a vector (Coeff) sorted by [a1;b1;c1;a2;b2;c2.....,an;bn;cn].
A plot is generated contains the interpolated data in red circles, quadratic splines.