FloooD
FloooD
/ squaremat.lua
Created
April 5, 2011 16:28
— forked from leegao/squaremat.lua
only for diagonalizable 2x2 matrices
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| function m_pow(matrix, n) | |
| local tr = matrix[1][1]+matrix[2][2] -- trace of matrix | |
| local s = math.sqrt((matrix[1][1]-matrix[2][2])^2+4*matrix[1][2]*matrix[2][1]) -- sqrt(tr^2 - 4*determinant) | |
| local r1 = 0.5*(tr+s) --1st eigenvalue | |
| local r2 = tr-r1 --2nd eigenvalue | |
| local r1n = r1^n | |
| local r2n = r2^n |