The use of script in the software Gemcom

Scripts are essentially the macros containing instructions for data manipulation in the form of mathematical and logical operations performed for the block model data. In order to create the useful filters and key indices, it is important to have a good understanding of expressions and how to use them. Expressions are simple formulae that can be created to define selection criteria for data in the workspace. There are two types of expressions: math expressions, which always result in a numeric value, and logical expressions, which always result in a true or false condition. Math expressions consist of up to three components: field specifiers, constants, and math operators. Logical expressions are made up of two math expressions separated by a logical operator.