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At 12:52 PM 6/6/2004, Frank Fleisher wrote:
>I jumped ship after TS2000i, so I don't know. But this problem
>existing in TS 7.0 seems ridiculous given that computers are much
>faster, more RAM, etc. Of course, they market to the amateur, and many love to
>load up charts with 900 googles of 1-tick bars, and having that loaded
>and overlayed with indicators and systems in a quick fashion is more important than
>anything else, including accuracy.
As I said before, TradeStation 7 uses double precision so this bug has disappeared...
The following is from the Help file for the SetFPCompareAccuracy function:
>>SetFPCompareAccuracy will allow you to override the default tolerance value, allowing for a lower or higher tolerance when comparing two floating point values to be equal.
>>
>>Two floating point values will be considered equal if “abs(Value1 – Value2) <= ” where is the tolerance value. The scope of this function will be limited to the Indicator, Strategy, or Function in which it was called.
>>
>>Versions of TradeStation prior to 7.0 used 4-byte single floating point values for variables and a less tolerance, approximately 5.0e-6, when comparing two variables for equality. Starting with Version 7.0 EasyLanguage uses 8-byte double floating point values and a very high tolerance of 2.2204460492503131e-016. This difference in tolerance checking may cause indicator values between version 7.0 and prior versions to be slightly different. Specifically, two values that were considered equal in versions prior to 7.0 are no longer considered equal in version 7.0. In order to address this issue we have changed the default tolerance value to 2.2204460492503131e-012.
Bob Fulks
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