Simply It is a C program that Calculates the interpolating function from giving points using Lagrange polynomial interpolation.

It Contains also a C library of a polynomials and Fractions that supports

• addition
• subtraction
• multiplication

and other useful operations.

I created this program so quick so i want to notice that : 

⋅⋅* the program dialogue is written in french
⋅⋅* the code is note well optimised especially memory management, but the code stills simple to understand ⋅⋅* I didn't quiet test it for bigger situations

Created with codeBlocks, you can start directly the exe file inside \bin folder or use CodeBlocks and change what ever you want 

the is also somme commented snippets that will help you to understand.