# 04 How are formulas interpreted?

The interpretation of the formula is done internally with the means of the formula calculator. The difference is that a formula is not interpreted with a fixed set of variable values, but just all specified ranges of all variables are combined and the resulting variable combinations are used systematically one after the other and each of these formulas is interpreted anew.

When the formula calculator has calculated, the result is taken and passed to the internal coordinate parser, which is also used for the insert function of the coordinates. This tries now to determine a valid coordinate from the result.

The whole process can fail at different places. So it can be that the formula calculator does not find a valid mathematical expression, or that something can be calculated here, but then no known coordinate format comes out with. Possible error sources can be

• Not all variables were entered
• Subformulas were not written in square brackets
• N and E for north and east have been interpreted as variables, if there are also the variables N and E (remedy is to simply omit north-N and east-E)
• Results of formulas or subformulas unexpectedly contain a minus or a decimal value
• The coordinate format was not recognized

Finished interpreted results are summarized in a coordinate list and output at the end in the desired coordinate format. In addition to the coordinates, the concrete variable values from which they arose are displayed.