Hitachi, Ltd.

Hitachi Vlsi Engineering Corp.

Hitachi, Vlsi Eng. Corp.

Yukio Umetani

Chisato Konno

Michiru Yamabe

Nobutoshi Sagawa

Miyuki Saji

Mitsuyoshi Igai

Tadashi Ohta

Ohata: Tadashi

Hiroyuki Hirayama

A program generating method for generating a FORTRAN program by use of a computer having the following steps of automatically selecting an optimal weight function for each equation of the system of partial differential equations including coupled plural variables and partial differential equations to effect a multiplication therebetween, performing a partial integration thereon, automatically selecting from a group of boundary conditions an optimal boundary condition for each partial differential equation to conduct a collation processing of the boundary condition, exchanging the order of the summation and the integration on the object variable to effect a discretize processing of the variable, assigning components to a coefficient matrix and a constant vector, and generating a FORTRAN program to solve the equations through a linear computation.

Method of automatically generating program for solving simultaneous

In a numerical simulation system, a method for displaying information includes the steps of generating output data of values which are dependent on at least one of coefficients and constants of a discretization equation at each mesh point, based on positions of the mesh points representing the analysis domain and having the partial differential equation defined therefor and simultaneous linear equations constructed by the discretization equations which are approximation equations of the partial differential equations; displaying the analysis domain on a display; and changing the display status of the display screen at the point corresponding to the mesh point depending on the output data at the mesh point.

Method and device for displaying information on simulation result in a

The entry of a problem describing program is assisted by a database or a display screen. An error in numerical calculation of the input problem describing program is automatically checked. A simulation program which interrupts the execution of a process requsted by a statement in the problem describing program which a user designates as a break point when the simulation program executes the process is automatically generated. At the time of interruption, the execution status of the simulation is diagnosed upon the user's request.

Method for automatically generating a simulation program for a physical

A method is provided for automatically generating a simulation program which numerically solves a partial differential equation which governs a physical quantity in a non-rectangular real space domain. The real partial differential equation is solved according to a boundary-fitted method by first transforming the original partial differential equation from a real space to a normal space. The upper limit of user work area memory available on the data processing apparatus and the number of mesh points extracted from the real space domain shape are considered in the transformation and to an extent control the transformation rule. Two program statements are thus generated, the first of which allocates data area for the particular variables in the work area memory. The second program statement defines the value of each variable in terms of one factor. The final step combines the partial differential equation and the first and second program statements into a simulation program which is used to solve the original partial differential equation.

Automatic generation method of a simulation program for numerically

A program-controlled computer includes a first unit for executing an addition or a substraction on a first floating-point data and a second floating-point data inputted thereto, a second unit for receiving the exponents of the first and second floating-point data, for determining whether or not an absolute value of a difference between the exponents exceeds a predetermined value defined as a number of digits of a mantissa of the first or second floating-point data, and for generating an interrupt signal when the absolute value exceeds the number of digits, and third unit connected to the second unit for interrupting a program being executed in response to the interrupt signal so as to execute an interrupt processing program associated with the interrupt signal.

Program-controlled computer with an interrupt capability for

The partial differential equations inputted with respect to an unknown quantity A are processed according to the finite element method in which simultaneous first-order equations equivalent to the partial differential equations are obtained, and then a matrix equation equivalent to the simultaneous first-order equations, namely, (k.sub.ij) (a.sub.i)=(d.sub.i) is processed to derive a coefficient {a.sub.j } so as to generate a program which calculates the unknown quantity A. For each group of a plurality of elements, the program calculates a contribution determined by the positions of the nodes associated with the elements with respect to a portion of matrix element group such as k.sub.lm and k.sub.ll and a portion of constant group such as d.sub.l and d.sub.m determined by the numbers assigned to a plurality of nodes contained in the group of a plurality of elements and then generates the final values of the matrix element group {k.sub.ij } and the constant {d.sub.i } from the contribution calculated for each group of a plurality of elements.

Method of automatic generation of a computer for numerical simulation of

An operation unit includes a first unit for calculating input data and for outputting an error data indicating an error generated as a result of the calculation by using such a mantissa data at a lower order as has been obtained midway of the calculation but is not used as an output result data; and a second unit for outputting error data of the calculation result data from the first-named error data and error data input accompanying the input data.

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Hachioji, Japan

Yukio Umetani