1.000000000006551e-005's sixteenth place to the right of the decimal is e-005.

Are you saying 1.000000000006551e-005 doesn't have an exact binary representation because its sixteenth place to the right of the decimal isn't an integer, its e-005?

Scientific notation (commonly referred to as "standard form") is a way of writing numbers that are too big or too small to be conveniently written in decimal form. Scientific notation has a number of useful properties and is commonly used in calculators and by scientists, mathematicians and engineers. Standard decimal notation Normalized...

Double values such as 1.5737300000000001 are stored as 1.57373 (if normalize double is used I assume). If normalize double isn't used, the double value 1.5737300000000001 would keep this value format, correct?

You need to read what people write . . .

"while NormalizeDouble(1.57373, 5) might produce a double value of 1.5737299999999999 " not 1.57373

"and often the value held is not exactly the same as the value that you think is being held."

"Scientific notation is a way of writing numbers that are too
big or too small to be conveniently written in decimal form. Scientific
notation has a number of useful properties and is commonly used in
calculators and by scientists, mathematicians and engineers.

In scientific notation all numbers are written in the form of"

a*10^band(a times ten raised to the power of b)THE END! I'd a put this at the very top above everything else. Background info belongs below.

I'll apply an analogy, "as difficult as finding a needle in a haystack". Combining text with calculations can complicate things. If text and calculations must be combined to explain an arithmetical calculation then the ratio should be 5-10 percent (text) to 90-95 percent (calculations). The article was informative so I can't complain but it's manner of placing "a*10^b
and (a times ten raised to the power of b)" in and amongst so much other data can confuse a reader. Background information is most helpful but should be placed below on a page so a reader won't feel like a mouse in a maze (where's the cheese!?). Hahahaha! ;)

Scientific notation (commonly referred to as "standard form") is a way of writing numbers that are too big or too small to be conveniently written in decimal form. Scientific notation has a number of useful properties and is commonly used in calculators and by scientists, mathematicians and engineers. Standard decimal notation Normalized...

"Data of double typeare output with the
accuracy of up to 16 digits after a decimal point, and can be output
either in traditional or in scientific format, depending on what
notation will be more compact. Data of float type are output with 5
digits after a decimal point. To output real numbers with another
accuracy or in a predefined format, use the DoubleToString() function."

USDJPY's price representation in 98.370 is data of float type (output at 5 digits after decimal).

USDJPY's price representation in -0.001999999999995339 is data of double type, traditional format (output at up to 16 digits after decimal).

Why does double -0.00199999999999533[9] return an 18th digit after the decimal if a double output is only up to 16 digits after the decimal?

"Data of double typeare output with the
accuracy of up to 16 digits after a decimal point, and can be output
either in traditional or in scientific format, depending on what
notation will be more compact. Data of float type are output with 5
digits after a decimal point. To output real numbers with another
accuracy or in a predefined format, use the DoubleToString() function."

USDJPY's price representation in 98.370 is data of float type (output at 5 digits after decimal).

USDJPY's price representation in -0.001999999999995339 is data of double type, traditional format (output at up to 16 digits after decimal).

Why does double -0.00199999999999533[9] return an 18th digit after the decimal if a double output is only up to 16 digits after the decimal?

Thank you

Prices are always double, 98.370 is a double. There are16 significant digits. Zeros are not significant.

RaptorUK: Very possibly, just tried that for the first time yesterday. Need to understand which files to backup and the consequences of copying older files back into the terminal and if it's possible to copy the history from a different Broker. I'll do some testing . . .

I closed down MT5, backed up my Bases folder, then copied my EURUSD folder from Broker 1 to Broker 2, I restarted MT5 logged in to my Broker 2 account and I now have the History from Broker 1 working with my Broker 2, also this History is used with the Strategy tester and my symbol properties are correct for my Broker 2.

So this is good news and is a way forward for me using M1 and above data . . .

I closed down MT5, backed up my Bases folder, then copied my EURUSD folder from Broker 1 to Broker 2, I restarted MT5 logged in to my Broker 2 account and I now have the History from Broker 1 working with my Broker 2, also this History is used with the Strategy tester and my symbol properties are correct for my Broker 2.

So this is good news and is a way forward for me using M1 and above data . . .

Why did you swap broker history? Congrats to you for your accomplishment.

3987

WhooDoo22:1.000000000006551e-005's sixteenth place to the right of the decimal is e-005.

Are you saying 1.000000000006551e-005 doesn't have an exact binary representation because its sixteenth place to the right of the decimal isn't an integer, its e-005?

3987

WhooDoo22:"this is how double values are stored"

Double values such as 1.5737300000000001 are stored as 1.57373 (if normalize double is used I assume). If normalize double isn't used, the double value 1.5737300000000001 would keep this value format, correct?

You need to read what people write . . .

"while NormalizeDouble(1.57373, 5) might produce a double value of

1.5737299999999999" not 1.57373"and often the value held is

notexactly the same as the value that youthinkis being held."RaptorUK:Read this too: http://en.wikipedia.org/wiki/Scientific_notation all of it.

I'm reading this (http://en.wikipedia.org/wiki/Scientific_notation) and am wondering why there's so much text explaining scientific notation, its unnecessary - for instance

"

Scientific notationis a way of writing numbers that are too big or too small to be conveniently written in decimal form. Scientific notation has a number of useful properties and is commonly used in calculators and by scientists, mathematicians and engineers.In scientific notation all numbers are written in the form of"

a*10^band(atimes ten raised to the power ofb)I'd a put this at the very top above everything else. Background info belongs below.THE END!, where the exponent

bis an integer, and the coefficientais any real number (however, see normalized notation below), called thesignificandormantissa. The term "mantissa" may cause confusion, however, because it can also refer to the fractional part of the common logarithm. If the number is negative then a minus sign precedesa(as in ordinary decimal notation).I'll apply an analogy, "as difficult as finding a needle in a haystack". Combining text with calculations can complicate things. If text and calculations must be combined to explain an arithmetical calculation then the ratio should be 5-10 percent (text) to 90-95 percent (calculations). The article was informative so I can't complain but it's manner of placing

"a*10^b and (in and amongst so much other data can confuse a reader. Background information is most helpful but should be placed below on a page so a reader won't feel like a mouse in a maze (where's the cheese!?). Hahahaha! ;)atimes ten raised to the power ofb)"Thank you

11879

WhooDoo22:I'm reading this (http://en.wikipedia.org/wiki/Scientific_notation) and am wondering why there's so much text explaining scientific notation, its unnecessary - for instance

...This not the right place to post such a comment. Wikipedia as a wiki ;-), you can participate on the elaboration of the content.

Hello MQL5 community,

http://www.mql5.com/en/docs/common/comment

"

Data of double typeare output with the accuracy of up to 16 digits after a decimal point, and can beoutput either in traditional or in scientific format, depending on what notation will be more compact.Data of float type are output with 5 digits after a decimal point. To output real numbers with another accuracy or in a predefined format, use the DoubleToString() function."USDJPY's price representation in 98.370 is data of float type (output at 5 digits after decimal).

USDJPY's price representation in -0.001999999999995339 is data of double type, traditional format (output at up to 16 digits after decimal).

Why does double -0.00199999999999533

[9]return an18th digitafter the decimal if a double output is only up to 16 digits after the decimal?Thank you

11879

WhooDoo22:Hello MQL5 community,

http://www.mql5.com/en/docs/common/comment

"

Data of double typeare output with the accuracy of up to 16 digits after a decimal point, and can beoutput either in traditional or in scientific format, depending on what notation will be more compact.Data of float type are output with 5 digits after a decimal point. To output real numbers with another accuracy or in a predefined format, use the DoubleToString() function."USDJPY's price representation in 98.370 is data of float type (output at 5 digits after decimal).

USDJPY's price representation in -0.001999999999995339 is data of double type, traditional format (output at up to 16 digits after decimal).

Why does double -0.00199999999999533

[9]return an18th digitafter the decimal if a double output is only up to 16 digits after the decimal?Thank you

3987

RaptorUK:Very possibly, just tried that for the first time yesterday. Need to understand which files to backup and the consequences of copying older files back into the terminal and if it's possible to copy the history from a different Broker. I'll do some testing . . .

I closed down MT5, backed up my Bases folder, then copied my EURUSD folder from Broker 1 to Broker 2, I restarted MT5 logged in to my Broker 2 account and I now have the History from Broker 1 working with my Broker 2, also this History is used with the Strategy tester and my symbol properties are correct for my Broker 2.

So this is good news and is a way forward for me using M1 and above data . . .

RaptorUK:I closed down MT5, backed up my Bases folder, then copied my EURUSD folder from Broker 1 to Broker 2, I restarted MT5 logged in to my Broker 2 account and I now have the History from Broker 1 working with my Broker 2, also this History is used with the Strategy tester and my symbol properties are correct for my Broker 2.

So this is good news and is a way forward for me using M1 and above data . . .

Why did you swap broker history? Congrats to you for your accomplishment.

Thank you

angevoyageur:Prices are always double, 98.370 is a double. There are 16 significant digits. Zeros are not significant.

Yes, of course :)

Thank you

3987

WhooDoo22:Why did you swap broker history? Congrats to you for your accomplishment.

I want to be able to control the History Data I use so that I can repeat tests (Strategy Tester) under controlled conditions.