v1.00 (Release date: May 10, 2025).

Calculates the real roots of a 3^rd order polynomial.

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v1.00 (Release date: March 20, 2024), Available in English.

Given three points P₁, P₂, P₃ with known coordinates (x₁, y₁), (x₂,y₂), (x₃,y₃), the quadratic interpolant is a second order curve which passes through these three points.
For a value x_P in the interval, the value y_P on the curve is calculated.

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v2.00 (Release date: March 19, 2024), Available in English.

In mathematics, bilinear interpolation is an extension of linear interpolation for interpolating functions of two variables (e.g., x and y) on a rectilinear 2D grid. The key idea is to perform linear interpolation first in one direction, and then again in the other direction. Although each step is linear in the sampled values and in the position, the interpolation as a whole is not linear but rather quadratic in the sample location. Read more on Wikipedia

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v2.00 (Release date: March 19, 2024), Available in English.

Given two points P₁, P₂ with known coordinates (x₁, y₁), (x₂,y₂), the linear interpolant is the straight line between these points.
For a value x_P in the interval, the value y_P along the straight line is calculated.

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v2.00 (Release date: March 19, 2024), Available in English.

Calculates the leap years of the calendar.

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v3.00 (Release date: May 10, 2025), Available in Greek.

Calculates the date of the Orthodox Easter and relevant fests for a given year (between 1900 and 2099). 

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