This function converts the hinged opening width to hinged opening angle.
function WidthToAngle extends Modelica.Icons.Function; input Modelica.Units.SI.Length lenAxs(min = 0) "Length of the hinged axis, the axis should be parallel to a window frame"; input Modelica.Units.SI.Length lenAxsToFrm(min = 0) "Distance from the hinged axis to the frame across the opening area"; input Modelica.Units.SI.Length width(min = 0) "Opening width of window sash"; output Modelica.Units.SI.Angle ang(min = 0, max = Modelica.Constants.pi/2) "Opening angle of window sash"; end WidthToAngle;