The Least Absolute Value Linear Fitting of D-u Line

The Linear relationship between shock wave velocity D and particle velocity u is very important to obtain high pressure equation of state and dynamic properties of materials under shock loading. In this paper, the least absolute value method is adopted to fit the D-u line of several kinds of materials, and comparing with the generally accepted least square method. Results show that for the experimental data which scatter small (e.g., non-porous samples), the two methods obtain almost the same results; but for the experimental data which scatter large (e.g., porous samples), the two methods obtain different results. Anyway, the least absolute value method has small average absolute error than the least square method. The reason of the different result between the two methods was addressed.