ISO 13584-20:1998 工业自动化和综合 部件库 第20部分：逻辑源：表达的逻辑模数.

标准编号：ISO 13584-20:1998

中文名称：工业自动化和综合 部件库 第20部分：逻辑源：表达的逻辑模数.

英文名称：Industrial automation systems and integration — Parts library — Part 20: Logical resource: Logical model of expressions

发布日期：1998-07

标准范围

ISO 13584的本部分规定:-泛型表达式的快速模式；-表达式的EXPRESS模式，用ISO 10303-11中定义的EXPRESS语言对允许的表达式子集进行建模，该语言对应于整数、实数、布尔值和字符串数据类型。此架构使用泛型表达式架构中定义的资源。以下内容属于ISO 13584本部分的范围:-涉及常量和变量的表达式交换；-检查数值表达式是否应计算为整数值的函数；-确保表达式在语义上正确的约束；-表达式中使用的变量或函数的计算；-检查表达式是否可以映射到SQL查询语言的函数。以下内容不在ISO 13584本部分的范围内:-在一定的环境下给变量赋值；-在给定上下文中计算表达式值的触发机制。

This part of ISO 13584 specifies:— an EXPRESS schema for generic expressions;— an EXPRESS schema for expressions, that models the subset of the allowed expressions in the EXPRESS language defined in ISO 10303-11 that corresponds to integer, real, Boolean and string data types. This schema uses the resources defined in the generic expression schema.The following are within the scope of this part of ISO 13584:— the exchange of expressions that involve both constants and variables;— the function that checks whether or not a numeric expression should evaluate to an integer value;— the constraints which ensure that an expression is semantically correct;— the computation of the variables or functions used in an expression;— the function that checks if an expression may be mapped on to the SQL query language. The following are outside the scope of this part of ISO 13584:— the assignment of values to variables within some context;— the triggering mechanism that computes the value of an expression in a given context.

标准预览图