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Re: [amibroker] AmiBroker 4.73.0 BETA released



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I origionally sent this post under a new title of  "AlmostEqual( x, y, ulps = 5 )" , and I received the following  message:
 
"We are unable to deliver the message from <mrdavis9@xxxxxxxxxx> to <amibroker @yahoogroups.com>.Your message was sent to a group that does not exist.  Please check to make sure you spelled the group name correctly."
 
This happens every once in a while.      Does this sometimes happen to others on this board?
============================================================
I understand the below  explanation to mean that  " ULPS=9"  would be roughly  0.00009% accurate.   Therefore, it is my understanding that   0.00009% accuracy is the LARGEST difference that  AlmostEqual( x, y, ulps = 9 )  will allow.  I would appreciate hearing  if  this a correct understanding of this new AlmostEqual function?  Ron D
================================================================
AlmostEqual( x, y, ulps = 5 )  is a helper function for comparing floating point numbers.It returns True if x and y are equal or almost equal upto defined accurracy (ulps).It is recommended to use this function instead of equality check (==) as itleads to more reliable comparisons and less headache caused by IEEE floating pointacurracy issues.
Parameters:x, y - the numbers or arrays to be compared,Ulps stands for "units in last place" and represents maximum relative error of the comparison. Since 32 bit IEEE floating point numbers have accurracy of 7 significant digits, 1 unit in last place(ulp) represents relative error of 0.00001 %. The default value of ulps parameter is 5 which gives roughtly 0.00005% "comparison sensitivity".
 
 
 
 
 
 
 
 
 
----- Original Message -----
Sent: Friday, September 16, 2005 5:42 PM
Subject: [amibroker] AmiBroker 4.73.0 BETA released

Hello,
 
A new beta version (4.73.0) of AmiBroker has just been released.

It is available for registered users only from the members area at:
http://www.amibroker.com/members/bin/ab4730beta.exe

(File size: 763 204 bytes, 763 KB)

If you forgot your user name / password to the members area
you can use automatic reminder service at:
http://www.amibroker.com/login.html

The instructions are available below and in the "ReadMe" file
( Help->Read Me menu from AmiBroker )

Best regards,
Tomasz Janeczko
amibroker.com
 

AmiBroker 4.73.0 Beta Read Me

September 17, 2005 0:36

THIS IS A BETA VERSION OF THE SOFTWARE. EXPECT BUGS !!!

Backup your data files and entire AmiBroker folder first!
IMPORTANT NOTE: This version uses new system to store indicators (in separate files), so old versions will not automatically "see" indicators created with new version.

INSTALLATION INSTRUCTIONS

IMPORTANT: This archive is update-only. You have to install full version 4.70 first.

Just run the installer and follow the instructions.

Then run AmiBroker. You should see "AmiBroker 4.73.0 beta" written in the About box.

Many thanks to all providing detailed descriptions how to reproduce given bug.

See CHANGE LOG below for detailed list of changes.

CHANGE LOG

  • OLE: Window object, new method ZoomToRange( From, To )
    ZoomToRange( From, To )
    From and To parameters are of any type that can be converted to date(you can use string or OLE date for example).

    Example code (JScript):

    AB=new ActiveXObject("Broker.Application");
    AW = AB.ActiveWindow;
    if( AW.ZoomToRange( "2005-04-01", "2005-08-01" ) )
    {
       WScript.Echo("Zoom successfull" );
    }

  • Fixed: Chart got shrinked a bit with each overlaid plot, now the Y scale does not change (unless really needed)

  • Fixed: XShift now works correctly with styleOwnScale and styleLeftScale

  • Fixed: Volume chart overlaid on price chart in log scale (overlay) was compressed to flat line, now it is fixed (volume chart overlay uses linear scale always)
    [#22262]

  • AFL: Added AlmostEqual function (completed: 2005-09-16)

    AlmostEqual( x, y, ulps = 5 )

    this is a helper function for comparing floating point numbers.It returns True if x and y are equal or almost equal upto defined accurracy (ulps).It is recommended to use this function instead of equality check (==) as itleads to more reliable comparisons and less headache caused by IEEE floating pointacurracy issues.

    Parameters:x, y - the numbers or arrays to be compared,Ulps stands for "units in last place" and represents maximum relative error of the comparison. Since 32 bit IEEE floating point numbers have accurracy of 7 significant digits, 1 unit in last place(ulp) represents relative error of 0.00001 %. The default value of ulps parameter is 5 which gives roughtly 0.00005% "comparison sensitivity".


    Example code:

    if( 1/3 == 0.3333333 )
    {
      printf("32-bit Floating point IEEE exact equality\n");
    }

    if( AlmostEqual( 1/3, 0.3333333 ) )
    {
      printf("Numbers are almost equal\n");
    }

    Thanks to Bruce Dawson for his fast routine.

  • Optimize() function now checks if min < max, step > 0 and checks if parameter name is not empty

  • Made Time&Sales case insensitive (when "case sensitive tickers" option is turned off")

  • OBV/AccDist/Chaikin functions adjusted to be SetForeign-aware

  • OLE: Application object new methods
    BOOL LoadLayout( filename )
    BOOL SaveLayout( filename )

    AB = new ActiveXObject("Broker.Application");
    AB.LoadLayout("C:\\Program Files\\AmiBroker\\Data\\Layouts\\Default.awl");

  • OLE: Window object new property: SelectedTab

    AB = new ActiveXObject("Broker.Application");
    AW = AB.ActiveWindow;
    tabindex = AW.SelectedTab; // read selected tab
    AW.SelectedTab = 3; //switch to tab 3
    AW.SelectedTab = tabindex; // restore originally selected tab

  • Fixed: Exception was generated when GetRTDataForeign was called with non-existing ticker

  • OLE: Window object new methods: LoadTemplate, SaveTemplate

    AB = new ActiveXObject("Broker.Application");
    AW = AB.ActiveWindow;
    AW.SaveTemplate("Test.abt");
    AW.LoadTemplate("Test.abt");

CHANGES FOR VERSION 4.72.1 (as compared to 4.72.0)

  • fixed out-of-memory problem sometimes occuring during scan of large (>512MB) databases

CHANGES FOR VERSION 4.72.0 (as compared to 4.71.1)

  • " Currency" field support in ASCII importer
    added command:
    $CURRENCY USD

    and field:

    $FORMAT Name,Currency$OVERWRITE 1$AUTOADD 1]

  • Added "Additional commands" field in the Import wizard for typing any extra $- commands that are not available via checkboxes

  • Added parameter to AddColumn/AddTextColumn to control column width

    AddColumn( ARRAY, "Caption", format = 1.2, color = colorDefault, bgcolor = colorDefault, width = -1);
    AddTextColumn( "Text", "Caption", format = 1.2, color = colorDefault, bgcolor = colorDefault, width = -1 );

  • AddToComposte new flag to work when Status("action")== actionPortfolio (completed: 2005-09-09)
    new flag is called atcEnableInPortfolio

    Example:

    if( Status("action" ) == actionPortfolio )

    {
    ... Custom backtest mode here ....
    AddToComposite( some_array, "~COMPOSITE", "X", atcFlagEnableInPortfolio | atcFlagDefaults );

    }

  • AFL added: tanh(), sinh(), cosh() functions
    Hyperbolic tangent, sine and cosine function

  • AFL functions: StrToUpper and StrToLower

  • Fixed: Tick ASCII import: last tick of previous import was deleted on subsequent import, now it is corrected

  • Function to detect mouse button state

    GetCursorMouseButtons() returns mouse button state at the time when chart formula is executed

    0 - if no mouse button is pressed
    1 - if left mouse button is pressed
    2 - if right mouse button is pressed
    4 - if middle mouse button is pressed

    plus combinations:3 - left + right5 - left + middle6 - right + middle 7 - left + right + middle]

  • GetRTDataForeign (retrieving values for other symbols)
    GetRTDataForeign( "field", "symbol")

  • Pane is not deleted if shrinked down to zero (prevents from accidential deletion of panes)

  • Plot function now has xshift parameter that allows to visually shift the chart past the last bar
    Example 20-bar Moving average shifted 10 bars into the future past the last bar:

    Plot(Close,"Close",colorBlack,styleCandle);Plot(MA(Close,20), "Shifted MA", colorRed, styleLine, Null, Null, 10 );

    Note that shift occurs during plotting and does not affect source array

  • Removed data source selection from preferences because it caused user confusion way too often

  • Stock.Currency available via OLE

  • Title variable now supports new special token {{OHLCX}} which is replaced at runtime by string "Open ..., Hi .... Lo ... Close (...%)" showing current price

    This way it is possible to implement formula that will show OHLC prices with number of decimal places set in the preferences.

    Example:

    SetChartOptions(0,chartShowArrows|chartShowDates);
    _N(Title = "{{NAME}} - {{INTERVAL}} {{DATE}} {{OHLCX}} {{VALUES}}" );
    Plot( C, "Close", ParamColor("Color", colorBlack ), styleNoTitle | ParamStyle("Style") | GetPriceStyle() );

  • user-definable number of decimal places in chart titles (completed: 2005-09-09)
    Number of decimal places displayed in default chart title is now user-definable inTools->Preferences->Miscellaneous"Decimal places in chart titles".

    Allowable values:
    -1 - dynamic mode (number of decimal places automatically adjusted)
    0..6 - fixed number of decimal places

  • QuoteArray resizing now uses heuristic algorithm to minimize memory fragmentation and increase performance

  • atcFlagDeleteValues now highlighted properly in the AFL editor

CHANGES FOR VERSION 4.71.1 (as compared to 4.71.0)

  • fixed compatibility problem with AmiQuote (due to changed order of OLE properties/method while AmiQuote was using old ones)
  • now ASCII importer in $TICKMODE does not delete quotes older than oldest (first) record in the imported file, so you can safely import tick data from subsequent files (older first, newest later)

CHANGES FOR VERSION 4.71.0 (as compared to 4.70.5)

  • AFL: added GetCursorXPosition() and GetCursorYPosition() functions

    Functions return current mouse cursor position.
    Values returned are equal to those visible in the status bar, and these functions require status bar to be visible. Returned values represent cursor position at the formula execution time (or few milliseconds before it) and accurracy is subject to pixel resolution of the screen (first cursor position is read in screen pixels (integer) and then converted to actual value therefore for example when screen resolution is 1024x768 maximum obtainable resolution in X direction is 0.1% and in Y direction 0.13%), also X values are snap to datetime of nearest data bar.

    It only makes sense to use these functions in indicator/interpretation code.

    Using them in AA window may yield random values.GetCursorXPosition() function returns X position in DateTime format (the same as used by DateTime() function).You can convert it to string using DateTimeToStr() function.GetCursorYPosition() returns Y position (as displayed in Y axis of the chart).


    Example:


    ToolTip="X="+DateTimeToStr(GetCursorXPosition()) +"\nY="+GetCursorYPosition();

  • AFL: added DateTimeToStr() and StrToDateTime() functions

    These functions allow to convert string to datetime format and vice versa.


    Example:

    ToolTip="X="+DateTimeToStr(GetCursorXPosition()) +"\nY="+GetCursorYPosition();]

  • Added ability to store charts as .GIF (in addition to PNG)

  • ASCII importer maximum supported line length is increased to 2048 characters

  • Fixed: .aflsafe files didn't get deleted automatically

  • Added N-volume bars charts and timeframe support.

    Custom N-volume bar intervals are definable (as usual) in Tools->Preferences->Intraday.

    TimeFrame functions were also extended to support N-volume bars using new TimeFrameMode() function calling

    TimeFrameMode( 0 );

    - switches time frame functions to time-based operation (the default)

    TimeFrameMode( 1 );

    - switches time frame functions to N-tick operation (positive values passed to TimeFrameSet are treated now as N-tick)

    TimeFrameMode( 2 );

    - switches time frame functions to N-volume bar operation (positive values passed to TimeFrameSet are treated nowas N-volme bars)


    Example:

    TimeFrameMode( 2 );
    TimeFrameSet( 50000 ); // 50'000 share bars..
    ...do something ...
    TimeFrameRestore();


    Note: N-volume bars are somewhat weird (compression of data to N-volume bar may actually deliver MORE output bars - for example if one tick is 1000 shares and you have specified 100V bars then single tick will be expanded to TEN 100V bars - ten times original size)
    TimeFrame functions are protected against array overrun and will not decompress beyond original array size (you will get an "Error 47. N-volume bar compressed data longer than base time frame").
    Also switching main time frame to some weird N-volume bar value will result in limiting the output to maximum twice original data size(without error message).
    You should keep that in mind and avoid using too small N-volume bar intervals that could lead to such condition.
    Also due to the nature of N-volume bars the only TimeFrameSet() function will yield correct N-volume bar values, TimeFrameGetPrice() may give slightly distorted results.
    It is also possible to use n-volume bars in TimeFrame functions without calling TimeFrameMode() - it is then necessary to specify n-volume bars as negative number offset by -1000000 (minus one million):

    TimeFrameSet( -1000000 - 2000 );

    // gives 2000V barsSimilarly formatted negative numbers will be reported by Interval() function when n-volume bars are selected.

     

  • OLE: Save As PNG / GIF callable from automation

    Example script:

    AB = new ActiveXObject("Broker.Application");
    AB.ActiveWindow.ExportImage("Test.png");

  • Plugin is not called when GetExtraData is used for symbol that has "use only local database" flag turned on, and NULL is returned instead of an error

  • Protected against changing application's current working directory by printing to file

  • Toolbar does not get wrapped when main frame window is resized

  • OLE: Analysis object has new method MoveWindow( x, y, width, height) that allows to control position and size of automatic analysis window

    AB = new ActiveXObject("Broker.Application");
    AB.Analysis.MoveWindow( 10, 10, 200, 200 );


    It has some restrictions on size: specified size can not besmaller than 10x10 pixels and can not be bigger than entire screen dimensions.
    Also when "No minimum size for resizing dialogs" box in UNCHECKED in Tools->Prefs->Misc it won't shink AA window below default size necessary to fully display all controls.

  • ASCII importer: added ability to import tick data from text files

    ASCII importer now allows tick data files to be imported.

    Tick data files consist of several records having the same timestamp.This makes it impossible to use normal import mode which assumes different (unique) timestampsfor each data row (when same timestamp is found then new data overwrites old).


    To turn on TICK mode you need to add manually

    $TICKMODE 1

    line to ASCII importer definition file.


    $TICKMODE is a special mode of importer that allows to import quotes that haveduplicate time stamps.

    It makes two assumptions:
    a) input data should come in the ascending time order (i.e. OLDER records first, LATEST records last)
    b) input data should consist of entire tick history because importer will DELETE any existing quotes (to avoid creating multiple copies of the same ticks).

    Once again: Turning on
    $TICKMODE 1
    will DELETE ANY QUOTES that already exist in the database and then will import all ticks from input data file.
    You have been warned.


    For example data files like this:

    MOL,0,20050606,162959,16400.0000,16400.0000,16400.0000,16400.0000,2MOL,0,20050606,162959,16400.0000,16400.0000,16400.0000,16400.0000,11MOL,0,20050606,162959,16400.0000,16400.0000,16400.0000,16400.0000,40


    Can be imported using the following definition file:


    $FORMAT Ticker, Skip, Date_YMD, Time, Open, High, Low, Close, Volume
    $SKIPLINES 1
    $SEPARATOR ,
    $CONT 1
    $GROUP 255
    $AUTOADD 1
    $DEBUG 1
    $TICKMODE 1


    Sometimes it happens that input files have invalid timestamps (seconds > 59).

    For example:

    MOL,0,20050606,162970,16400.0000,16400.0000,16400.0000,16400.0000,2

    Please take a closer look at first line shown in this example it has time:16:29:70 (you see 70 seconds !)

    So I had to add a special flag to the importer that works around such data errors.

    It is called $ALLOW99SECONDS 1 and will convert all records with invalid seconds (i.e greater than 59)to 59s.
    So record stamped 16:29:70 will be treated as 16:29:59

    Now for tick mode to work with such incorrect records you would need to add two lines to ASCII importer definition:

    $TICKMODE 1
    $ALLOW99SECONDS 1

HOW TO REPORT BUGS

If you experience any problem with this beta version please send detailed description of the problem (especially the steps needed to reproduce it) to bugs at amibroker.com



Please note that this group is for discussion between users only.

To get support from AmiBroker please send an e-mail directly to
SUPPORT {at} amibroker.com

For other support material please check also:
http://www.amibroker.com/support.html





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