A method for determining constants in the linear combination of exponentials

Abstract: Shifting a numerically given function $b_1 \exp a_1t + \dots+ b_n \exp a_n t$ we obtain a fundamental matrix of the linear differential system $\dot{y}=Ay$ with a constant matrix $A$. Using the fundamental matrix we calculate $A$, calculating the eigenvalues of $A$ we obtain $a_1, \dots, a_n$ and using the least square method we determine $b_1, \dots, b_n$.

Keywords: fundamental matrix, linear differential system, shifted exponentials, eigenvalues, the least square method

Classification (MSC91): 65D15, 65L99, 34A30

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