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Live_EngineLive Engine is a child type of Live Request that represents all specification parameters related to a Live Feeds Engine, the purpose of which is to fetch data from a specified live feeds provider in regular time intervals.
Note that the creation of an object of type Live Engine does not automatically start the corresponding engine.
The latter is achieved by running once the special Excel formula dsLive with its single input argument set equal to the handle name of the created object.
Subsequent calls of the dsLive formula are ignored as long as the object's contents remain the same.
But if the object's contents change, calling the dsLive formula results in the termination of the prior engine and the simultaneous launch of a new engine with the new parameters.
Also note that while several different objects of type Live Engine may be created, corresponding to different engine specifications, only one engine per provider can be alive at any given time.
Starting a new engine on a given provider results in the termination of any existing alive engine on the same provider.
An alive engine acquires data from the provider's server in periodic time intervals, but does not display these data on the spreadsheet.
The latter can be achieved by using anyone of the two special Excel formulas dsLiveGet or dsLive
If you choose the dsLive approach, you must first create an object of type Live Display Async and pass its handle name as the single input argument to dsLive
Note the dsLiveGet is declared volatile so that it automatically runs as soon as new feeds arrive and a recalculation event is raised.
Provided Excel is in automatic calculation mode, such a recalculation event is raised automatically upon the arrival of new feeds if the Auto Refresh setting is turned ON.
While the engine operation does not necessarily result in the display of the received feeds, the latter can still be automatically stored in a local text file if the flag Key Live Engine::Store Feeds is switched on.