Structure of a complex formula

You can combine MM-Talk functions as required to create longer formulas. You can also make several variable assignments in a formula; the individual assignments must then be separated from each other by semicolons.

_$Variable1 :=_Expression1;
...
_$Variables :=_Expressionn;
Result expression

The variable assignment must be at the beginning of the formula. Once a variable has been assigned, it can be used as often as required in any expression of a formula.

The following example, in which a formula is created to calculate a price difference from the previous day, shows you step by step how to create a complex formula:

1. The input object is a security. First, the current close time series is queried and stored in the variable "$Close":

   CODE

   $Close:=Close;

2. The same procedure is used for the close time series from the previous day; the result is assigned to the variable "$Close1".

   CODE

   $Close1:=$Close.Before[1];
   
   

3. Finally, the difference between the two time series is calculated. The result is also a time series:
   
   

   CODE

   $Close-$Close1

4. The finished formula is:

   CODE

   $Close:=Close;
   $Close1:=$Close.Before[1];
   $Close-$Close1

By using the variables cleverly, you save one access to the close time series for each call of the formula in this example.