TriangleSingularity A simple package that calculates triangle loop using the Feynman approach, reduced to a single integral. Evaluation of amplitude triangleloop(m1², m2², m3², M1², M2², M3²) Position of singularities M3² = Polynomial([0im, 1.0]) P = landau_determinant(m1², m2², m3², M1², M2², M3²) roots(P)