Patent Document ID: 4819161
Application ID: 06900424
Patent Status: 1

Claim One:
1. A method for automatically generating, by use of a computer, a program which calculates an unknown quality (A) within a calculation object region (S1, S2), based upon a finite element method, said automatic generation being performed in response to input information specifying a boundary of the calculation objective region, a division condition of the boundary, a partial differentiation equation related to the unknown quantity, and a boundary condition to be satisfied by the unknown quantity on the boundary, said method comprising the steps of: (a) dividing the calculation objective region (S1, S2) into element regions (E1, E2,. .. ) according to the division condition; (b) generating , based upon the partial differential equation, a first mathematical expression representing a portion within an arbitrary coefficient (k.sub.ij) to be calculated for a matrix equation (k.sub.ij) (a.sub.i)=(d.sub.i), said portion being dependent on an element region which includes nodes (N.sub.i, N.sub.j) related to the coefficient, and a second mathematical expression representing a portion within an arbitrary instant (d.sub.i) to be calculated for the matrix equation, said portion being dependent on an element region which includes a node (N.sub.i) related to the constant, wherein a solution of the matrix equation enables the unknown quantity (A) to be represented as a linear combination (.SIGMA..sub.i a.sub.i .phi..sub.i) of basis functions .phi..sub.j each defined with respect to a respective node (N.sub.i) of the element regions; and (c) generating a program which calculates the coefficients ((k.sub.ij)) and constants ((d.sub.i)); said program generation including the steps of (c1) generating first and second program portions based upon said first mathematical expression and generating a third program portion based upon said second mathematical expression, wherein said first program portion calculates respective first portions and respective second portions dependent upon positions of nodes (N.sub.i, N.sub.j, and N.sub.k) of one of the element region, so as to renew, by the respective first portions, respective values already calculated for respective diagonal coefficients (K.sub.ii, K.sub.jj, K.sub.kk) related to respective nodes of the one element region, and so as to renew, by the respective second portions, respective values already calculated of respective non-diagonal coefficients (K.sub.ij K.sub.ji, K.sub.jk, K.sub.kj, K.sub.ki, K.sub.ik) related to respective pairs of nodes of the one element region, and wherein the second program portion calculates respective third portions dependent upon the positions of the plurality of nodes of the one element region, so as to renew, by the respective third portions respective value already calculated for a respective constants of the matrix equation (d.sub.i, d.sub.j, d.sub.k) related to the one element region and (c3) generating a second program portion for enabling said first to third program portions to be executed for different ones of the element regions of the calculation objective region.