With respect to real time data feeds into MS and the generation of multiple alets on the last bar when new ticks arrive, the simplest solution is to disable live-bars and only generate signals once the
entire bar has been completed; another involves setting a trap so that
all signals are computed on the second last bar, but the alert is
displayed on the very last bar (so it will only ever display once)...
These solutions often don't match the requirement of the RT traders,
especially over longer time frames such as 30 minutes or longer. There
is a method using external functions which allows RT ticks to be received and alert conditions and
indicators etc computed. It counts the times the condition is true on
each tick for the last bar, then returns the counter to MS with the
number of times the condition has been met and you can set the alert
function to trigger as you like. This solution cannot be implemented in MSFL and requires the use of external functions.
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