Program generation method for particles simulation

• US 5,438,526 A
• Filed: 07/07/1992
• Issued: 08/01/1995
• Est. Priority Date: 07/12/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Itoh, Satoshi, Ihara, Sigeo
• Primary Examiner(s): Ramirez, Ellis B.
• Assistant Examiner(s): Stamber, Eric W.
• Application Number:
  US07/914,747
• Time in Patent Office: 1,120 Days
• Field of Search: 395/700, 395/922, 395/500, 364/578, 364/191
• US Class Current: 703/2
• CPC Class Codes: G06F 17/13 Differential equations using digital differential analysers G06F7/64
• CPC Class Codes: G06F 2111/10 Numerical modelling
• CPC Class Codes: G06F 30/23 using finite element methods [FEM] or finite difference methods [FDM]
• CPC Class Codes: Y10S 706/922 Computer program preparation

Abstract

A generation method of particle simulation programs includes a translation and discretization process of equation of motion of particles for recognizing attributes of a space and particles based on information of the particle simulation to generate expressions of calculations, tables, and internal data and a generation process of programs for creating calculation programs and simulation input data from the generated expressions of calculations, tables, and internal data. According to information inputted from a screen of a graphic terminal, various control conditions are produced to control processes of the simulation.

Claims

1. A program generation method for particles simulation of generating particle simulation programs in a computer which has a memory and to which an input/output device is connected, comprising the following steps of:

(1) inputting particle simulation information from the input/output device to analyze a physical phenomenon as individual motion of a plurality of particles in a spatial region, reducing a volume of input particle simulation information to form reduced inputted information, and storing the reduced inputted information in the memory, said particle simulation information including,

a description of attributes of particles representing particle species and a number of particles as objects of the simulation,

a description of a shape of a spatial region representing a boundary condition in which a physical phenomenon is generated,

a description of control conditions of an environment of the simulation, and

equations of motion dominating behaviors of interactive particles in time and space;

(2) generating, according to the reduced inputted information stored in the memory, information describing specifications of the particle simulation programs according to each of said plurality of particles; and

(3) creating, based on the information describing specifications of the particle simulation programs, the particle simulation programs and input data necessary therefor.

2. The program generation method of claim 1 wherein the step of reducing a volume of input particle simulation information includes the step of averaging the particle simulation information for the plurality of particles in the spatial region.

3. A method according to claim 1, wherein said step (2) includes a process for:

interpreting a description of a shape of a spatial region in which a physical phenomenon is generated, the description being included in the particle simulation information; and

generating an internal representation of domain including dimensions of the space, the shape of region, and boundary conditions.

4. A method according to claim 1, wherein said step (2) includes a process for:

interpreting a description of attributes of particles as objects of the simulation, the description being included in the particle simulation information; and

generating an internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items.

5. A method according to claim 1, wherein said step (2) includes a process for:

extracting, from control conditions of an environment of the simulation, boundary conditions and processes associated therewith, changes in simulation conditions at predetermined times and processes associated therewith;

generating a table for storing therein correspondences between conditions and processes; and

creating an internal representation of auxiliary processes describing the contents of the extracted processes.

6. A method according to claim 1, wherein said step (2) includes a process for:

interpreting and discretizing the equations of motion of particles; and

creating an internal description of expressions including asymptotic equations in a tree graph format.

7. A method according to claim 1, wherein said step (2) includes:

(1) a process for;

interpreting a description of a shape of a spatial region in which a physical phenomenon is generated, the description being included in the particle simulation information; and

generating an internal representation of domain including dimensions of the space, the shape of region, and boundary conditions;

(2) a process for;

interpreting a description of attributes of particles as objects of the simulation, the description being included in the particle simulation information; and

generating an internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items;

(3) a process for;

extracting, from control conditions of an environment of the simulation, boundary conditions and processes associated therewith, changes in simulation conditions at predetermined times and processes associated therewith;

generating a table for storing therein correspondences between the control conditions and processes; and

creating an internal representation of auxiliary processes describing the contents of the extracted processes; and

(4) a process for;

interpreting and discretizing the equations of motions of particles; and

creating an internal description of expressions including asymptotic equations in a tree graph format.

8. A method according to claim 1, wherein the information generated by said step (2) to describe therein the specifications includes:

an internal representation of domain including dimensions of the space, the shape of region, and boundary conditions;

an internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items;

a table for storing therein correspondences between the control conditions and processes; and

an internal description of expressions specifying the equations of motion of particles.

9. A method according to claim 1, wherein said step (3) includes a process for generating a header program according to the internal representation of domain including dimensions of the space, the shape of region, and boundary conditions and the internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items, the internal representations being included in the information generated to describe therein the specifications,

the header program comprising specification statements of various variables including arrays.

10. A method according to claim 1, wherein said step (3) includes a process for generating a program, according to the internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items, the internal representation being included in the information generated to describe therein the specifications,

the program reading the input data including various initial values of the particle attributes necessary for the simulation and the data and for storing the data in a file.

11. A method according to claim 1, wherein said step (3) includes a process for generating a program, according to the table for storing therein correspondences between the control conditions and processes, the table being included in the information generated to describe therein the specifications,

the program controlling a process procedure of the simulation.

12. A method according to claim 1, wherein said step (3) includes a process for generating a program, according to the internal representation of expressions specifying the equations of motion of particles, the internal representation being included in the information generated to describe therein the specifications,

the program numerically integrating asymptotic equations associated with the equations of motion.

13. A method according to claim 1, wherein said step (3) includes a process for generating a program for auxiliary calculations, according to the internal representation of expressions specifying the equations of motion of particles, the internal representation being included in the information generated to describe therein the specifications,

the program calculating various physical quantities necessary for the equations of motion.

14. A method according to claim 1, wherein said step (3) includes:

(1) a process for generating a header program according to the internal representation of domain including dimensions of the space, the shape of region, and boundary conditions and the internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items, the internal representations being included in the information generated to describe therein the specifications,

the header program comprising specification statements of various variables including arrays;

(2) a process for generating a program, according to the internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items, the internal representation being included in the information generated to describe therein the specifications,

the program reading the input data including various initial values of the particle attributes necessary for the simulation and the data and for storing the data in a file;

(3) a process for generating a program, according to the table for storing therein correspondences between the control conditions and processes, the table being included in the information generated to describe therein the specifications,

the program controlling a process procedure of the simulation

(4) a process for generating a program, according to the internal representation of expressions specifying the equations of motion of particles, the internal representation being included in the information generated to describe therein the specifications,

the program numerically integrating asymptotic equations associated with the equations of motion; and

(5) a process for generating a program for auxiliary calculations, according to the internal representation of expressions specifying the equations of motion of particles, the internal representation being included in the information generated to describe therein the specifications,

the program calculating various physical quantities necessary for the equations of motion.

15. A method according to claim 1, wherein the particle simulation program generated by said step (3) includes:

a header program comprising specification statements of various variables including arrays;

a program for reading the input data including various initial values of particle attributes necessary for the simulation;

a program for controlling the process procedure of the simulation;

a program for numerically integrating asymptotic equations associated with the equations of motion of particles; and

a program for auxiliary calculations for calculating various physical quantities necessary for the equations of motion of particles.

16. A method according to claim 1, wherein said step (1) includes, for specifying various setting items included in the information of the particle simulation, the following steps of:

displaying a list including the setting items on a screen of the input/output device; and

effecting a selection of one of the items by an indicating apparatus associated with the input/output device.

17. A method according to claim 16, wherein the items other than the item thus selected are presented on the screen in a presentation manner different from that used for the selected item.

18. A method according to claim 1, wherein said step (1) includes, for inputting control conditions included in the information of the particle simulation, the following steps of:

inputting data associated with a predetermined physical quantity from the input/output device and thereby displaying on the screen of the input/output device a graph indicating changes in the control conditions;

reading a change in the physical quantity from the changes presented in the displayed graph;

generating a description of control conditions of the physical quantity;

sorting the contents of the description of control conditions according to a sequence of time; and

outputting the sorted control conditions as the particle simulation information to the memory.

19. A method according to claim 1, wherein said step (1) includes, for inputting initial arrangement of each particle included in the information of the particle simulation, the following steps of:

inputting coordinates values of said initial arrangement from the input/output device and thereby displaying on the screen of the input/output device a mark indicating presence of each particle at a position corresponding to the coordinates values

reading said coordinates values;

generating a description of said initial arrangement of each particle; and

outputting the described initial arrangement as the particle simulation information to the memory.

21. The program generation method of claim 2 wherein the step of reducing a volume of input particle simulation information includes the step of averaging the particle simulation information for the plurality of particles in the spatial region.

20. A program generation method for particles simulation of generating particle simulation programs in a computer which has a memory and to which an input/output device is connected, comprising the following steps of:

(1) inputting particle simulation information from the input/output device to analyze a physical phenomenon as motion of a plurality of particles in a spatial region, reducing a volume of input particle simulation information to form reduced inputted information, and storing the reduced inputted information in the memory, wherein the particle simulation information includes,

a description of attributes of particles as objects of the simulation,

a description of a shape of a spatial region in which a physical phenomenon is generated,

a description of control conditions of an environment of the simulation, and

equations of motion dominating behaviors of particles in time and space;

(2) generating, according to the reduced inputted information stored in the memory, information describing specifications of the particle simulation programs, said step (2) including;

(a) a process for;

interpreting the description of a shape of a spatial region in which a physical phenomenon is generated, the description being included in the particle simulation information; and

generating an internal representation of domain including dimensions of the space, the shape of region, and boundary conditions

(b) a process for;

interpreting the description of attributes of particles as objects of the simulation, the description being included in the particle simulation information; and

generating an internal representation of variables including numeric values associated with species of particles, the number of particles, and various initial setting information items;

(c) a process for;

extracting, from control conditions of an environment of the simulation, boundary conditions and processes associated therewith, changes in simulation conditions at predetermined times and processes associated therewith;

generating a table for storing therein correspondences between conditions and processes; and

creating an internal representation of auxiliary processes describing the contents of the extracted processes; and

(d) a process for;

interpreting and discretizing the equations of motion of particles; and

creating an internal description of expressions including asymptotic equations in a tree graph format; and

(3) creating, based on the information describing specifications of the particle simulation programs, the particle simulation programs and input data necessary therefor.