BarPeriod

Type:

BarOffset

TimeFrame

FrameOffset

Type:

Remarks:

• Use the bar function for special bars that are not bound to a certain bar period.
• BarPeriod can be set by script from one second (1./60) to one week (7*24*60 = 10080). Bar periods above 1 are rounded to a multiple of minutes. The [Period] slider moves in fixed steps corresponding to the standard bar periods of trading platforms; directly setting BarPeriod places the slider at the position closest to the BarPeriod value. If BarPeriod is set directly in the script, the slider is locked.
• In [Test] mode, bar generation is based on the UTC time stamps of ticks in the historical price data. All ticks that fall in the bar period contribute to the bar. For instance, a 10-minute bar ending at 12:00 contains all ticks with timestamps from 11:50:00.000 until 11:59:59.999. If the tick covers several prices, its time stamp should be from its close price. If historical time stamps are from the open or the middle price instead, you can use the TickFix variable for adjusting them. In [Trade] mode, bar generation is based on UTC time from the PC clock, not on the broker's server time for avoiding sync problems by connection interruptions and Internet lag.
• On short bar periods it is recommended to set the TICKS flag and use high resolution .t1 price data. It's mandatory on bar periods of less than a minute. For this, set History to ".t1" and BarPeriod to the number of seconds divided by 60, f.i. BarPeriod = 5./60. for 5 seconds. Mind the decimal; 5/60 would be considered an int and thus evaluate to 0. For extremely short bar periods, make sure that TickTime is always less than a bar period.
• For bar periods longer than a week, set BarPeriod = 1440 and use TimeFrame for setting up monthly or quarterly time periods. 
• BarPeriod and BarOffset affect the sampling of price data. Therefore they must be set in the first run before selecting the asset, must not change afterwards, and must not be optimized. TimeFrame and FrameOffset can be set anytime and can be optimized without restrictions.
• Historical price data should have sufficient resolution so that any BarPeriod contains at least one historical tick during market hours. If BarOffset is nonzero, historical and lookback data need accordingly higher resolution. For instance, with a daily bar period price data should have at least 10-minutes resolution when BarOffset is set so that bars end at 15:40. 
• If BarOffset is 0, bars begin and end at day/hour boundaries. For preventing that daily bars would begin and end at 00:00 midnight (and thus reflect the prices from the previous, not from the current day), BarOffset has a default value of 940 (equivalent to 15:40) on daily and weekly bars. Alternatively, set BarOffset to the time when you want the script to trade; for example, BarOffset = 60*9+30; for trading at market open at 9:30. Witb the default bar offset, weekly bars end on Friday 15:40.
• All time zone settings assume UTC time for price history. If price history is in local time and the time of day is relevant for the system, either convert the timestamps to UTC or use BarZone.
  

TimeFrame vs. BarPeriod:

• TimeFrame is not the same as BarPeriod. The differences are listed below. If multiple time frames or time offsets are not required, set the time frame with BarPeriod only. This uses the lowest possible number of bars and results in the highest speed for testing and training. 
• Barperiod determines the bar chart and the frequency of the run function, while TimeFrame affects the price functions, the shifting of series, and the bars at which advise and trade calls are executed.
• Commands to enter or exit trades in the run function are only executed when the TimeFrame has ended at the current bar. But trade entry, stop, or profit targets are observed at any bar period. The run function itself is executed at any bar period, but the frame function can be used for restricting code execution to the end of the current time frame.
• TimeFrame is normally not synchronized to day/hour boundaries, while BarPeriod is. For synchronizing time frames to days or hours, use the frameSync() function. For aligning daily time frames to a certain market hour in a certain time zone, use the AssetFrame variable.
• TimeFrame has no effect on variables in bar period units, f.i. LookBack, UnstablePeriod, LifeTime, or WaitTime. For extending those time periods, multiply the variable value with the number of bars per time frame.
• TimeFrame does not affect indicators that do not use a Data series, but directly the current asset price series. This is mentioned in the description of the indicator.
• Recursive indicators from the TA-Lib such as EMA or ATR require UnstablePeriod to be adapted to their maximum time frame. 

Examples:

#define H24 (1440/BarPeriod)
#define H4 (240/BarPeriod)
#define H1 (60/BarPeriod)
... 
BarPeriod = 60; // 1 hour (60 minutes) bars
...
// create a 4-hour price series ///////////////////////////////////
TimeFrame = H4;
vars PriceH4 = series(price());
 

// create a 24-hour price series /////////////////////////////////
TimeFrame = H24;
vars PriceH24 = series(price());

// skip bars outside market hours
static int SkippedBars = 0;
if(!market(ET,0)) {
   TimeFrame = 0;
   SkippedBars--; // count negative number of bars outside market hours
} else if(TimeFrame == 0) {
   TimeFrame = SkippedBars;
   SkippedBars = 0;
} else
  TimeFrame = 1;
vars PriceInMarketHours = series(price());

// create a daily price series (equivalent to AssetZone) ////////
static int BarsPerDay = 0;
if(hour(0) < hour(1)) { // day change  
  TimeFrame = BarsPerDay; // end the frame
  BarsPerDay = 0;
} else {
  TimeFrame = 0; // inside the frame
  BarsPerDay--;  // count negative number of bars per day
}
vars PriceD1 = series(price());

// alternative: a midnight-aligned price series using frameSync()
StartWeek = 10000;
TimeFrame = frameSync(H24);
vars PriceD1 = series(price());

// back to 1-hour time frames
TimeFrame = 1;					
...

See also: