iBarShift

iBarShift is one of the more useful functions to have in a programming arsenal. I'm just not sure how to use it fully =D.


Let's say I wanted to find the bar on the hour chart which includes the time 15:43.

If I were to use:

iBarShift(NULL, 0, StrToTime("15:43"). True);

Why don't I get the proper bar?

int iBarShift( string symbol, int timeframe, datetime time, bool exact=false)
Search for bar by open time. The function returns bar shift with the open time specified. If the bar having the specified open time is missing, the function will return -1 or the nearest bar shift depending on the exact.

Parameters:
symbol - Symbol the data of which should be used to calculate indicator. NULL means the current symbol.
timeframe - Timeframe. It can be any of Timeframe enumeration values. 0 means the current chart timeframe.
time - value to find (bar's open time).
exact - Return mode when bar not found. false - iBarShift returns nearest. true - iBarShift returns -1.

so.... since your time isn't exact, try using iBarShift(NULL, 0, StrToTime("15:43"), false);

one more thing that'll be interesting to find out. it says it'll return the nearest index if you set exact to false.

Assuming you're using this on a 1Hr chart,
15:43 although lies in the 15:00 candle, it's actually nearer to 16:00 candle. so does iBarShift return the 15:00 candle or 16:00 candle? do let me know your findings. Thanks =)

regards,
Zen

ok I've just confirmed with a simple test script. 15:45 will return the index for candle 15:00 which is what you want.

but one thing to note with the use of StrToTime() function. if you don't put in a date, it uses the date from your computer. e.g., my chart is still at 23rd Feb but my computer due to my timezone difference is already at 24th Feb. regardless of what time I use, the resultant date time will always be having 24th as it's day attribute.

e.g. so StrToTime("15:45") yields 2009.2.24 15:45 which is in the future and is actually closer to the CURRENT candle (now) so it always returns 0

only when I use iBarShift(NULL, 0, StrToTime("2009.02.23 15:45"), false), will it return 1 which is the current candle index for the 15:00 candle.

hope this helps.

regards,
Zen