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My rpn calculator can't compute negative numbers...

TheAutomator
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UEZ Universalist

UEZ

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Posted (edited)

UEZ,

trying to figure out what you just did there,

  • first you check what the token is,
  • if it is a number:
  •     you push it to the stack,
  • if it is an operator:
  •     Operand1 = first value
  •         if the last char of Operand1 is a '-' then Operand1 = '-' & the value of Operand1 without the '-'
  •     Operand2 = second value
  •         if the last char of Operand2 is a '-' then Operand2 = '-' & the value of Operand2 without the '-'
  •         (tell me if i'm wrong here, i'm a noob if it comes to regex..)
  •     then let autoit evaluate(Operand1 & operator token & Operand2)
is this correct?

well, the shunting yard algorithm i made returns the tokens token by token, '3-' could never be a single token, to would rather be '3', '-'

 

 

Well, if the token is e.g. 2- then the "-" must be a the beginning to calculate properly.

What 6. and 8. is doing, is to move the "-" to the beginning  by capturing everything before "-" and adding "-" manually to the string.

It is the same as e.g.

$s = "3.125-"
ConsoleWrite("-" & StringTrimRight($s, 1) & @CRLF)

but don't ask me why I used regex.

 

Br,

UEZ

Edited by UEZ

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  • Solution
jchd Universalist

jchd

Posted
  • Solution
Posted

Again that will never work in general. Of course you or me or anyone else can exhibit myriads of RPN expressions where sign change and subtract can use the same symbol but that doesn't work in the general case.

You have to decide whether an operator or function is monadic, dyadic, a.s.o. because confusing different arities changes the semantics of the expression.

Consider the input (1 - cos(-x)) / sqrt(5) . In RPN it is:

1 ←

x ←

± ←               ; this is sign change, whatever symbol you use except -

cos ←

- ←

5 ←

sqrt ←

/ ←

Using - as well for unary minus, you get:

1 ←

x ←

- ←               ; this is NOT sign change

cos ←

- ←

5 ←

sqrt ←

/ ←

That is: -cos(1 - x) / sqrt(5)

This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

TheAutomator Polymath

TheAutomator

Posted
  • Author
Posted (edited)

UEZ,

ok, i get what you did now.

interesting idea, :) i'm going to test a few things with that code if i may

jchd,

I examined the udf from guinness and saw what he did  :idea:

he used whitespace to see which symbol is a minus and which is not..

here some pseudocode:

Func ShuntingYard_Calculate(sExpression)
    aChar = Split(sExpression,""); <<<split to chars>>>
    hStack = array()'Create a stack to push/pop to.
    iNumber1 = 0
    iNumber2 = 2
    sDigits = ""
    sToken = ""
    For i = 0 To UBound(aChar)
        sToken = aChar(i)
        If isnumeric(sToken) Then
            sDigits = sDigits & sToken
        ElseIf isoperator(sToken) Then
            iNumber2 = Pop(hStack)
            iNumber1 = Pop(hStack)
            call Push(rpn(iNumber1, iNumber2, sToken), hStack)
        ElseIf sToken = " " And Not(sDigits = "") Then; <<<TEST FOR '-'>>>
            If isnumeric(sDigits) Then
                iNumber1 = sDigits
                Call Push(iNumber1, hStack)
            End If
            sDigits = ""
            iNumber1 = 0
        End If
    Next
    return= Pop(hStack)
EndFunc

the problem with your code is that you cant use e.g. "1 - 5 -" as input, and this would mean that i have to fully reprogram the tokenizer and find out a way to see

if the '-' is monadic or not and replace it with another symbol if needed..

tell me if i'm wrong or misunderstood you.

Edited by TheAutomator

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jchd Universalist

jchd

Posted
Posted

That isn't "a problem with my code", that's how a RPN calculator works. Whatever trick you use to differenciate the operations you do need to use something different. Using a separate symbol is simpler. On actual calculators the key is often marked +/- but there is no such symbol in Unicode. ± is Alt 0177 in western latin.

This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

guinness Universalist

guinness

Posted
Posted

Thanks jchd.

As I implemented the shunting yard algorithm according to the specification, I see no bug in my code (see signature). 

UDF List:

 
_AdapterConnections() • _AlwaysRun() • _AppMon() • _AppMonEx() • _ArrayFilter/_ArrayReduce • _BinaryBin() • _CheckMsgBox() • _CmdLineRaw() • _ContextMenu() • _ConvertLHWebColor()/_ConvertSHWebColor() • _DesktopDimensions() • _DisplayPassword() • _DotNet_Load()/_DotNet_Unload() • _Fibonacci() • _FileCompare() • _FileCompareContents() • _FileNameByHandle() • _FilePrefix/SRE() • _FindInFile() • _GetBackgroundColor()/_SetBackgroundColor() • _GetConrolID() • _GetCtrlClass() • _GetDirectoryFormat() • _GetDriveMediaType() • _GetFilename()/_GetFilenameExt() • _GetHardwareID() • _GetIP() • _GetIP_Country() • _GetOSLanguage() • _GetSavedSource() • _GetStringSize() • _GetSystemPaths() • _GetURLImage() • _GIFImage() • _GoogleWeather() • _GUICtrlCreateGroup() • _GUICtrlListBox_CreateArray() • _GUICtrlListView_CreateArray() • _GUICtrlListView_SaveCSV() • _GUICtrlListView_SaveHTML() • _GUICtrlListView_SaveTxt() • _GUICtrlListView_SaveXML() • _GUICtrlMenu_Recent() • _GUICtrlMenu_SetItemImage() • _GUICtrlTreeView_CreateArray() • _GUIDisable() • _GUIImageList_SetIconFromHandle() • _GUIRegisterMsg() • _GUISetIcon() • _Icon_Clear()/_Icon_Set() • _IdleTime() • _InetGet() • _InetGetGUI() • _InetGetProgress() • _IPDetails() • _IsFileOlder() • _IsGUID() • _IsHex() • _IsPalindrome() • _IsRegKey() • _IsStringRegExp() • _IsSystemDrive() • _IsUPX() • _IsValidType() • _IsWebColor() • _Language() • _Log() • _MicrosoftInternetConnectivity() • _MSDNDataType() • _PathFull/GetRelative/Split() • _PathSplitEx() • _PrintFromArray() • _ProgressSetMarquee() • _ReDim() • _RockPaperScissors()/_RockPaperScissorsLizardSpock() • _ScrollingCredits • _SelfDelete() • _SelfRename() • _SelfUpdate() • _SendTo() • _ShellAll() • _ShellFile() • _ShellFolder() • _SingletonHWID() • _SingletonPID() • _Startup() • _StringCompact() • _StringIsValid() • _StringRegExpMetaCharacters() • _StringReplaceWholeWord() • _StringStripChars() • _Temperature() • _TrialPeriod() • _UKToUSDate()/_USToUKDate() • _WinAPI_Create_CTL_CODE() • _WinAPI_CreateGUID() • _WMIDateStringToDate()/_DateToWMIDateString() • Au3 script parsing • AutoIt Search • AutoIt3 Portable • AutoIt3WrapperToPragma • AutoItWinGetTitle()/AutoItWinSetTitle() • Coding • DirToHTML5 • FileInstallr • FileReadLastChars() • GeoIP database • GUI - Only Close Button • GUI Examples • GUICtrlDeleteImage() • GUICtrlGetBkColor() • GUICtrlGetStyle() • GUIEvents • GUIGetBkColor() • Int_Parse() & Int_TryParse() • IsISBN() • LockFile() • Mapping CtrlIDs • OOP in AutoIt • ParseHeadersToSciTE() • PasswordValid • PasteBin • Posts Per Day • PreExpand • Protect Globals • Queue() • Resource Update • ResourcesEx • SciTE Jump • Settings INI • SHELLHOOK • Shunting-Yard • Signature Creator • Stack() • Stopwatch() • StringAddLF()/StringStripLF() • StringEOLToCRLF() • VSCROLL • WM_COPYDATA • More Examples...

Updated: 22/04/2018

jchd Universalist

jchd

Posted
Posted

Let's see where we land:

; Create postfix notation (RPN) from infix notation.
    ConsoleWrite(StringFormat('%s: == %s', '2 ^ ( 1 - - 3 )', ShuntingYard_Parse('2 ^ ( 1 - - 3 )')) & @CRLF)
    ConsoleWrite('Reference: ???' & @CRLF)

We get:

2 ^ ( 1 - - 3 ): == 2 1  - 3 - ^

Feed a rpn processor with that:

2 ←      ; stack is (2)

1 ←      ; stack is (2, 1)

-           ; does 2-1 = 1 so stack is now (1)

3 ←      ; stack is (1, 3)

-           ; does 1-3 = -2 so stack is now (-2)

^          ; error! not enough operands

That's hardly correct.

I'm not saying that you didn't follow the referenced page you linked, I'm saying that one needs distinct symbols for unary vs binary "minus" in the rpn stack. Second point, unary minus (aka sign change) wasn't considered in the algorithm you implemented: it can only deal with binary minus (aka substract) and not unary minus.

This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

guinness Universalist

guinness

Posted
Posted

Well that should be pointed out in the algorithm specification.

UDF List:

 
_AdapterConnections() • _AlwaysRun() • _AppMon() • _AppMonEx() • _ArrayFilter/_ArrayReduce • _BinaryBin() • _CheckMsgBox() • _CmdLineRaw() • _ContextMenu() • _ConvertLHWebColor()/_ConvertSHWebColor() • _DesktopDimensions() • _DisplayPassword() • _DotNet_Load()/_DotNet_Unload() • _Fibonacci() • _FileCompare() • _FileCompareContents() • _FileNameByHandle() • _FilePrefix/SRE() • _FindInFile() • _GetBackgroundColor()/_SetBackgroundColor() • _GetConrolID() • _GetCtrlClass() • _GetDirectoryFormat() • _GetDriveMediaType() • _GetFilename()/_GetFilenameExt() • _GetHardwareID() • _GetIP() • _GetIP_Country() • _GetOSLanguage() • _GetSavedSource() • _GetStringSize() • _GetSystemPaths() • _GetURLImage() • _GIFImage() • _GoogleWeather() • _GUICtrlCreateGroup() • _GUICtrlListBox_CreateArray() • _GUICtrlListView_CreateArray() • _GUICtrlListView_SaveCSV() • _GUICtrlListView_SaveHTML() • _GUICtrlListView_SaveTxt() • _GUICtrlListView_SaveXML() • _GUICtrlMenu_Recent() • _GUICtrlMenu_SetItemImage() • _GUICtrlTreeView_CreateArray() • _GUIDisable() • _GUIImageList_SetIconFromHandle() • _GUIRegisterMsg() • _GUISetIcon() • _Icon_Clear()/_Icon_Set() • _IdleTime() • _InetGet() • _InetGetGUI() • _InetGetProgress() • _IPDetails() • _IsFileOlder() • _IsGUID() • _IsHex() • _IsPalindrome() • _IsRegKey() • _IsStringRegExp() • _IsSystemDrive() • _IsUPX() • _IsValidType() • _IsWebColor() • _Language() • _Log() • _MicrosoftInternetConnectivity() • _MSDNDataType() • _PathFull/GetRelative/Split() • _PathSplitEx() • _PrintFromArray() • _ProgressSetMarquee() • _ReDim() • _RockPaperScissors()/_RockPaperScissorsLizardSpock() • _ScrollingCredits • _SelfDelete() • _SelfRename() • _SelfUpdate() • _SendTo() • _ShellAll() • _ShellFile() • _ShellFolder() • _SingletonHWID() • _SingletonPID() • _Startup() • _StringCompact() • _StringIsValid() • _StringRegExpMetaCharacters() • _StringReplaceWholeWord() • _StringStripChars() • _Temperature() • _TrialPeriod() • _UKToUSDate()/_USToUKDate() • _WinAPI_Create_CTL_CODE() • _WinAPI_CreateGUID() • _WMIDateStringToDate()/_DateToWMIDateString() • Au3 script parsing • AutoIt Search • AutoIt3 Portable • AutoIt3WrapperToPragma • AutoItWinGetTitle()/AutoItWinSetTitle() • Coding • DirToHTML5 • FileInstallr • FileReadLastChars() • GeoIP database • GUI - Only Close Button • GUI Examples • GUICtrlDeleteImage() • GUICtrlGetBkColor() • GUICtrlGetStyle() • GUIEvents • GUIGetBkColor() • Int_Parse() & Int_TryParse() • IsISBN() • LockFile() • Mapping CtrlIDs • OOP in AutoIt • ParseHeadersToSciTE() • PasswordValid • PasteBin • Posts Per Day • PreExpand • Protect Globals • Queue() • Resource Update • ResourcesEx • SciTE Jump • Settings INI • SHELLHOOK • Shunting-Yard • Signature Creator • Stack() • Stopwatch() • StringAddLF()/StringStripLF() • StringEOLToCRLF() • VSCROLL • WM_COPYDATA • More Examples...

Updated: 22/04/2018

jchd Universalist

jchd

Posted
Posted

True, that's why it isn't the whole story.

Unary common functions/operators like unary -, inverse (1/x), sqrt, 3root, trig functions, ..., derivative, transpose, determinant, ...

Binary functions/operators like + - * / ^ Mod, so many other

Ternary functions like PowerMod(a,b,n) which is Mod(a ^ b, n), and so on.

...

Take any 4-operation (+ - * /) very basic calculator without parenthesis capability and see how _you_ (human with a brain) handle 2*(1 - -3)

You immediately realize that -3 has to be handled with care unless the calculator offers a +/- sign change key.

Singing that you don't need a calculator for that is silly!

This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

TheAutomator Polymath

TheAutomator

Posted
  • Author
Posted
jchd,

 

Ok, I see..

so if i want to do (1 - - 1) i have to replace the last '-' with something else in the tokenizer i guess?

(1 - - 1) becomes (1 - ± 1)

I also noticed that interpreters can handle multiple minus symbols after each other and even with pluses inside of them like: "1+--+-+-+1"  :wacko:

(1 + - - - 1) becomes (1 + ± ± ± 1)

(- 1) becomes (± 1) then?

guinness,

 

I cant follow you there :P

Is the minus multiple thing something you are going to implement in your rpn calculator? (last private message you send me)

or are you simply saying that it is the job for the tokenizer to see which minus is what?

regards,

TheAutomator

Retro Console, NestedArrayDisplay UDF foldermaker-pro-clone

 

guinness Universalist

guinness

Posted
Posted

It's not something I will implement any time soon, sorry. I thought it was an issue with my code, but it would be a workaround for the limitation of Shunting-Yard alogrithm.

I only created the Shunting-Yard algorithm concept as I was bored at the time and just interested in porting something I had previously created in C#.

UDF List:

 
_AdapterConnections() • _AlwaysRun() • _AppMon() • _AppMonEx() • _ArrayFilter/_ArrayReduce • _BinaryBin() • _CheckMsgBox() • _CmdLineRaw() • _ContextMenu() • _ConvertLHWebColor()/_ConvertSHWebColor() • _DesktopDimensions() • _DisplayPassword() • _DotNet_Load()/_DotNet_Unload() • _Fibonacci() • _FileCompare() • _FileCompareContents() • _FileNameByHandle() • _FilePrefix/SRE() • _FindInFile() • _GetBackgroundColor()/_SetBackgroundColor() • _GetConrolID() • _GetCtrlClass() • _GetDirectoryFormat() • _GetDriveMediaType() • _GetFilename()/_GetFilenameExt() • _GetHardwareID() • _GetIP() • _GetIP_Country() • _GetOSLanguage() • _GetSavedSource() • _GetStringSize() • _GetSystemPaths() • _GetURLImage() • _GIFImage() • _GoogleWeather() • _GUICtrlCreateGroup() • _GUICtrlListBox_CreateArray() • _GUICtrlListView_CreateArray() • _GUICtrlListView_SaveCSV() • _GUICtrlListView_SaveHTML() • _GUICtrlListView_SaveTxt() • _GUICtrlListView_SaveXML() • _GUICtrlMenu_Recent() • _GUICtrlMenu_SetItemImage() • _GUICtrlTreeView_CreateArray() • _GUIDisable() • _GUIImageList_SetIconFromHandle() • _GUIRegisterMsg() • _GUISetIcon() • _Icon_Clear()/_Icon_Set() • _IdleTime() • _InetGet() • _InetGetGUI() • _InetGetProgress() • _IPDetails() • _IsFileOlder() • _IsGUID() • _IsHex() • _IsPalindrome() • _IsRegKey() • _IsStringRegExp() • _IsSystemDrive() • _IsUPX() • _IsValidType() • _IsWebColor() • _Language() • _Log() • _MicrosoftInternetConnectivity() • _MSDNDataType() • _PathFull/GetRelative/Split() • _PathSplitEx() • _PrintFromArray() • _ProgressSetMarquee() • _ReDim() • _RockPaperScissors()/_RockPaperScissorsLizardSpock() • _ScrollingCredits • _SelfDelete() • _SelfRename() • _SelfUpdate() • _SendTo() • _ShellAll() • _ShellFile() • _ShellFolder() • _SingletonHWID() • _SingletonPID() • _Startup() • _StringCompact() • _StringIsValid() • _StringRegExpMetaCharacters() • _StringReplaceWholeWord() • _StringStripChars() • _Temperature() • _TrialPeriod() • _UKToUSDate()/_USToUKDate() • _WinAPI_Create_CTL_CODE() • _WinAPI_CreateGUID() • _WMIDateStringToDate()/_DateToWMIDateString() • Au3 script parsing • AutoIt Search • AutoIt3 Portable • AutoIt3WrapperToPragma • AutoItWinGetTitle()/AutoItWinSetTitle() • Coding • DirToHTML5 • FileInstallr • FileReadLastChars() • GeoIP database • GUI - Only Close Button • GUI Examples • GUICtrlDeleteImage() • GUICtrlGetBkColor() • GUICtrlGetStyle() • GUIEvents • GUIGetBkColor() • Int_Parse() & Int_TryParse() • IsISBN() • LockFile() • Mapping CtrlIDs • OOP in AutoIt • ParseHeadersToSciTE() • PasswordValid • PasteBin • Posts Per Day • PreExpand • Protect Globals • Queue() • Resource Update • ResourcesEx • SciTE Jump • Settings INI • SHELLHOOK • Shunting-Yard • Signature Creator • Stack() • Stopwatch() • StringAddLF()/StringStripLF() • StringEOLToCRLF() • VSCROLL • WM_COPYDATA • More Examples...

Updated: 22/04/2018

jchd Universalist

jchd

Posted
Posted

My intention wasn't to spread FUD (Fear, Uncertainty and Doubt) but simply to draw attention on a possible pitfall that could be painful to fix after the fact.

This wonderful site allows debugging and testing regular expressions (many flavors available). An absolute must have in your bookmarks.
Another excellent RegExp tutorial. Don't forget downloading your copy of up-to-date pcretest.exe and pcregrep.exe here
RegExp tutorial: enough to get started
PCRE v8.33 regexp documentation latest available release and currently implemented in AutoIt beta.

SQLitespeed is another feature-rich premier SQLite manager (includes import/export). Well worth a try.
SQLite Expert (freeware Personal Edition or payware Pro version) is a very useful SQLite database manager.
An excellent eBook covering almost every aspect of SQLite3: a must-read for anyone doing serious work.
SQL tutorial (covers "generic" SQL, but most of it applies to SQLite as well)
A work-in-progress SQLite3 tutorial. Don't miss other LxyzTHW pages!
SQLite official website with full documentation (may be newer than the SQLite library that comes standard with AutoIt)

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