Test to see if messages are ready to be received from other worker
isDataAvail = labProbe
isDataAvail = labProbe(srcWkrIdx)
isDataAvail = labProbe('any',tag)
isDataAvail = labProbe(srcWkrIdx,tag)
[isDataAvail,srcWkrIdx,tag] = labProbe
labindex of a particular worker from which to test for a message.
Tag defined by the sending worker's labSend function to identify particular data.
String to indicate that all workers should be tested for a message.
Logical indicating if a message is ready to be received.
isDataAvail = labProbe returns a logical value indicating whether any data is available for this worker to receive with the labReceive function.