Integral value calculating device and function gradient calculating

Abstract

An integral value calculating device is used for calculating an integral value of a function, and a function gradient calculating device is used for calculating the gradient of the graph for a function. The object is to obtain a transport coefficient, etc. by designating an appropriate calculation range in analyzing the data output by a molecular dynamics simulator. In the integral value calculating device, a graph display unit outputs a graph according to received data, for example, a graph of a time correlation function F(t) of the time differential W'(t) to the dynamics volume W(T), in the format applicable to an external unit, for example, a display unit. A calculation range input unit designates an integral range for the function according to the position data externally input for the graph. An integral value calculating unit calculates an integral value for a function F(t), for example, for the designated integral range. In the function gradient calculating device, two points on a graph in which the gradient should be calculated are designated according to the position data input for a graph displayed on the display unit, for example. Then, a function gradient calculating unit calculates the gradient of the graph, for example, the graph for the mean square displacement G(t) of the dynamics volume W(t), between the two designated points.