different lengbar

[Sir Zhang]

if i  reqHistoricalData more than once with different lengbar

like this:

# historicalData handler

con.register(myprintData, message.historicalData) 

# set different barLength

barLength='1 H'

con.reqHistoricalData(0,      

                          contract,

                          endDateTime,

                          '1 Y'

                          barLength,

                          'TRADES',

                          0, 1) 

  

time.sleep(1)  

# set different barLength

barLength='15 mins'

con.reqHistoricalData(0,      

                          contract,

                          endDateTime,

                          '1 Y'

                          barLength,

                          'TRADES',

                          0, 1) 

now my func myprintData will receive many data, 

how can  i know which is belong to 1 H or  15 mins？

[Derek Tishler]

https://www.interactivebrokers.com/en/software/api/apiguide/java/reqhistoricaldata.htm

The first value of the function, in your case 0, is the id for identifying the messages from the server. You can parse the incoming data based on this value once you give each request a unique value.

And just for fun, in case you are wondering about historical data limits and a nice chart for pairing the allowed duration/granularity pairs,you can check here:
https://www.interactivebrokers.com/en/software/api/apiguide/tables/historical_data_limitations.htm