Re: Big difference between builder and trader
Miroslav, as per code 402 bars is enough, where does the need for thousands come in?
- footon
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- Popov
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Re: Big difference between builder and trader
There are two requirements that depends on the indicator calculation formula:
1. Bars required to calculate the first indicator value. For example if we have MA with period=100 and shift=50. The required bars (First Bar in indicators code) = period + shift + 3 = 153 bars. Where I set 3 bars for the logical rule. For example, "MA rises" needs minimum 2 values, where "MA changes direction" needs 3 additional bars.
2. Bars required to reduce the history dependence below Sigma. Where Sigma is an acceptable error. some indicators as Exponential MA uses the whole history for calculating a value. The formula is CurrentEMA = PreviousEMA*(1-Coeff) + CurrentBar*Coeff.
We cannot say preliminarily how many bars would be necessary to reduce the deviation below a value that the signals will not deviate. As a standard FSB Pro uses Sigma = PointValue/2 or for 5 digits quotation, Sigma = 0.000005.
We have to check individually how many bars we need for each indicator and market.
28 2015-05-18 21:49:43 (edited by aysamatik 2015-05-18 21:55:31)
Re: Big difference between builder and trader
never mind, i changed my mind.
29 2015-05-23 17:11:55 (edited by hannahis 2015-05-23 17:22:19)
Re: Big difference between builder and trader
I'm totally confuse with the bars calculation and I'm not sure how many out there knows how to calculate how many bars needed for their strategy to work.
So can I then put the bars as high as I can? For Example, in the 1 min MT4 chart, when I put the cursor as Footon mentioned previously, I can find out how many bars and in my chart, it has 45146 bars. Do I or can I put 45000 in the Maximum Data Bars input section?
Is there any harm in putting more Bars than what the strategy require? Eg strategy needs only 1000, and under the EA input for Maximum Data Bars, I put 10,000? What would happen? Would my strategy still work?
Is there any harm in putting more Bars than what the MT4 chart has? Eg the MT4 1 min chart has 45146 Bars and I put 50,000 Bars in the EA input for Maximum Data Bars? What would happen? Would my strategy still work?
Since I don't know how to calculate the bars needed for each strategies (and I have so many strategies, too much for me to calculate them one by one), can I then put the cursor on the chart and input the 45145 bars into the EA input section?
- Popov
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Re: Big difference between builder and trader
I'm totally confuse with the bars calculation and I'm not sure how many out there knows how to calculate how many bars needed for their strategy to work.
If you are confused, you are on the right way. Be sure 99% of the traders have no idea what they are doing.
So can I then put the bars as high as I can?
You can, bunt it is not recommended. The more bars you use, the more memory your expert will consume. Eventually the expert may become slower, to miss some ticks and to execute a deal with slippage.
Is there any harm in putting more Bars than what the MT4 chart has?
The expert will not trade in such a case. It will report a "Not enough bars" error.
I'm not aware of a tool that calculates an indicator precision as a function of the data series length. However, I intend to make such tool and to include it in FSB and the exported EAs.
For now you can start from 500 or 1000 bars and to compare the values shown in the expert with the values in the FSB chart. If the values differ increase the required bars. Do that until the indicator values stop changing and use the shorter number of bars.
31 2015-05-24 08:43:55 (edited by hannahis 2015-05-24 08:46:32)
Re: Big difference between builder and trader
Thanks Popov for solving this Bar counting "mystery" for me 
I'm looking forward for the function whereby the Bar calculation could automatically done by FSB and export to MT4, however, do have the option to over-ride this automated input and allow manual input in any case may be needed.