Curve generation of implicit functions by incremental computers

Department of Electronic Engineering, Yamagata University, Yonezawa, Japan
Computers & Graphics (Impact Factor: 0.91). 01/1983; 7(2):161-167. DOI: 10.1016/0097-8493(83)90007-9
Source: DBLP


The conventional numerical solution of an implicit function f(x, y) = 0 is substantially complicated for calculating by any computer. We propose a new method representing the argument of the implicit function as a unary function of a parameter, t, if the continuous and unique solution of f(x, y) = 0 exists. The total differential constitutes simultaneous differential equations of which the solution about x and y is unique. The Newton-Raphson method must be used to calculate the values near singular points of an implicit function and then the sign of dt has to be decided according to four special cases. Incremental computers are suitable for curve generation of implicit functions by the new method, because the incremental computer can perform more complex algorithms than the analog computer and can calculate faster than the digital computer. This method is easily applicable to curve generation in three-dimensional space.

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