# pdaPointXY

Define X and Y (micron); an expression is ok.## Structure

This element does not have elements. The attributes are shown below, in a*sorted per type*fashion.

<point a="..." x="..." y="..." ... > ... </point>

### XSD

The schema file can be downloaded or viewed at xPDK_Base.## Details

### a

*Type pdaExpression documentation:*Define an expression.

Expression need to be commonly evaluated by many software, so having a restricted set of math / types and so on is key. In PDAFlow lib2/expr there is a yacc/lex parser available with some unit support as well as double / complex expressions. An alternative is tinyexpr, but this is more restrictive, so may be very unhandy for things like waveguide model expressions.

### x

*Type pdaExpression documentation:*Define an expression.

Expression need to be commonly evaluated by many software, so having a restricted set of math / types and so on is key. In PDAFlow lib2/expr there is a yacc/lex parser available with some unit support as well as double / complex expressions. An alternative is tinyexpr, but this is more restrictive, so may be very unhandy for things like waveguide model expressions.

### y

*Type pdaExpression documentation:*