Examples of Cant Attainment Methods

View examples of the XML formats you can use for various cant attainment methods.

This section explains the formulas used in some common cant attainment methods.

By Transition Lengths, and % On Straights if No Transition

The following example shows the XML format you can use to calculate transition chainages based on transition lengths. If a curve group does not contain transitions, then a specified percentage of the transition takes place on the straights.

<CantAttainmentMethod name="by spiral lengths; and % on tangents if no spiral">
<TransitionFormula type="LRtoFC" formula="IF({l}, {l}, {t})"/> 
<TransitionFormula type="LRtoBC" formula ="IF({l}, {p}*{l}, {p}*{t})"/> 
</CantAttainmentMethod>

By Lengths from a Table, and Maximum Cant on Straights if No Transition

The following example shows the XML format you can use to calculate transition chainages using transition lengths from a table. If a curve group does not contain transitions, then a specified maximum cant value is applied on the straights.

<CantAttainmentMethod name="by lengths from table; and max cant on tangents if no spiral">
<TransitionFormula type="LRtoFC" formula="{t}"/> 
<TransitionFormula type="LRtoBC" formula ="IF({l}, {p}*{t}, IF({a}&{d}<={a}, {d}*{t}/{a}, {t}))"/> 
</CantAttainmentMethod>