PDS(7.1) Procedures: Difference between revisions

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(Created page with "QB64 was created to be compatible with Quick Basic 4.5 only as it was the most popular version. The following sub-procedures have been created to do things that were available in PDS versions of Quick Basic 7.0 and 7.1. ==CURRENCY== ===MKC$=== PDS could use the CURRENCY variable type and had the MKC$ function to convert those values to '''8 byte''' ASCII string values. QB64 can convert _FLOAT currency amounts to strings using _MK$ with _INTEGER64 value...")
 
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     CVal = CurrVal * 10000 '        multiply float value by 10 thousand
     CVal = CurrVal * 10000 '        multiply float value by 10 thousand
     MKC = {{Cl|_MK$}}({{Cl|_INTEGER64}}, CVal)
     MKC = {{Cl|_MK$}}({{Cl|_INTEGER64}}, CVal)
{{Cl|END FUNCTION}} '' ''
{{Cl|END FUNCTION}}
{{CodeEnd}}
{{CodeEnd}}
: ''Note:'' The [[_FLOAT]] currency amount must be multiplied by 10000 before it is converted to the [[ASCII]] string value.
: ''Note:'' The [[_FLOAT]] currency amount must be multiplied by 10000 before it is converted to the [[ASCII]] string value.
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===CVC===
===CVC===
PDS also had the CVC function to convert MKC$ currency string values back to currency amounts. QB64 can use [[_CV]] with [[_INTEGER64]] to convert those '''8 byte''' values back to [[_FLOAT]] currency values. The procedure gets the currency string from a file:
PDS also had the CVC function to convert MKC$ currency string values back to currency amounts. QB64 can use [[_CV]] with [[_INTEGER64]] to convert those '''8 byte''' values back to [[_FLOAT]] currency values. The procedure gets the currency string from a file:
{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|SCREEN}} 12
{{Cl|SCREEN}} 12
{{Cl|DIM}} currency {{Cl|AS}} {{Cl|STRING}} * 8
{{Cl|DIM}} currency {{Cl|AS}} {{Cl|STRING}} * 8
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     CV = {{Cl|_CV}}({{Cl|_INTEGER64}}, CurrStr)
     CV = {{Cl|_CV}}({{Cl|_INTEGER64}}, CurrStr)
     CVC = CV / 10000 '                  divide by 10 thousand
     CVC = CV / 10000 '                  divide by 10 thousand
{{Cl|END FUNCTION}} '' ''
{{Cl|END FUNCTION}}
{{CodeEnd}}
{{CodeEnd}}
: ''Note:'' The [[_FLOAT]] currency amount must be divided by 10000 to create up to 4 decimal point places.
: ''Note:'' The [[_FLOAT]] currency amount must be divided by 10000 to create up to 4 decimal point places.
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Currency values can be [[PUT]] directly into [[BINARY]] or [[RANDOM]] files using an [[_INTEGER64]] variable value.
Currency values can be [[PUT]] directly into [[BINARY]] or [[RANDOM]] files using an [[_INTEGER64]] variable value.


{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}


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{{Cl|CLOSE}} #1
{{Cl|CLOSE}} #1


{{Cl|END}} '' ''
{{Cl|END}}
{{CodeEnd}}
{{CodeEnd}}


===GET===
===GET===
When currency values are [[PUT]] directly into a [[BINARY]] or [[RANDOM]] file, [[_INTEGER64]] can [[GET]] them directly. Then divide by 10 ^ 4:  
When currency values are [[PUT]] directly into a [[BINARY]] or [[RANDOM]] file, [[_INTEGER64]] can [[GET]] them directly. Then divide by 10 ^ 4:
{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}
{{Cl|DIM}} curr {{Cl|AS}} {{Cl|_INTEGER64}}, currency {{Cl|AS}} {{Cl|_FLOAT}}
{{Cl|OPEN}} "currency.bin" {{Cl|FOR (file statement)|FOR}} {{Cl|BINARY}} {{Cl|AS}} #1 ' any binary file holding PDS currency values
{{Cl|OPEN}} "currency.bin" {{Cl|FOR (file statement)|FOR}} {{Cl|BINARY}} {{Cl|AS}} #1 ' any binary file holding PDS currency values
Line 74: Line 74:
{{Cl|PRINT}} currency
{{Cl|PRINT}} currency


{{Cl|END}} '' ''
{{Cl|END}}
{{CodeEnd}}
{{CodeEnd}}
: ''Note:'' The currency value can be any [[SINGLE]], [[DOUBLE]] or [[_FLOAT]] floating decimal point value that will hold the range of values.
: ''Note:'' The currency value can be any [[SINGLE]], [[DOUBLE]] or [[_FLOAT]] floating decimal point value that will hold the range of values.
Line 85: Line 85:


This PDS(7.1) '''derived DIR$ function''' returns a filename or a list when more than one exist. The file spec can use a path and/or wildcards.
This PDS(7.1) '''derived DIR$ function''' returns a filename or a list when more than one exist. The file spec can use a path and/or wildcards.
{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|FOR...NEXT|FOR}} i = 1 {{Cl|TO}} 2
{{Cl|FOR...NEXT|FOR}} i = 1 {{Cl|TO}} 2
     {{Cl|PRINT}}
     {{Cl|PRINT}}
Line 125: Line 125:
     {{Cl|END IF}}
     {{Cl|END IF}}
     DIR$ = DirList$(Index%)
     DIR$ = DirList$(Index%)
{{Cl|END FUNCTION}} '' ''
{{Cl|END FUNCTION}}
{{CodeEnd}} {{small|Code by Ted Weissgerber}}
{{CodeEnd}} {{small|Code by Ted Weissgerber}}
:''Explanation:'' The function will verify that a file exists (even if it is empty) by returning it's name or it returns an empty string if no file exists. It can return a list of file names by using an empty string parameter("") after sending a wildcard spec to get the first file name. The number of file names found is returned by using the SHARED variable, '''DIRCount%'''. Unlike the PDS DIR$ function, '''it MUST use an empty string parameter until QB64 supports optional parameters!''' The function does NOT delete empty files.
:''Explanation:'' The function will verify that a file exists (even if it is empty) by returning it's name or it returns an empty string if no file exists. It can return a list of file names by using an empty string parameter("") after sending a wildcard spec to get the first file name. The number of file names found is returned by using the SHARED variable, '''DIRCount%'''. Unlike the PDS DIR$ function, '''it MUST use an empty string parameter until QB64 supports optional parameters!''' The function does NOT delete empty files.

Revision as of 02:18, 23 January 2023

QB64 was created to be compatible with Quick Basic 4.5 only as it was the most popular version. The following sub-procedures have been created to do things that were available in PDS versions of Quick Basic 7.0 and 7.1.

CURRENCY

MKC$

PDS could use the CURRENCY variable type and had the MKC$ function to convert those values to 8 byte ASCII string values. QB64 can convert _FLOAT currency amounts to strings using _MK$ with _INTEGER64 values: 

SCREEN 12
DIM value AS _FLOAT
value = 12345678901234.6789 '    any currency value with up to 4 decimal point places

_PRINTSTRING (1, 50), "[" + MKC$(value) + "]" ' show ASCII string value

END

FUNCTION MKC$ (CurrVal AS _FLOAT) 'converts currency amount to PDS or VB currency string
    DIM CVal AS _INTEGER64
    CVal = CurrVal * 10000 '        multiply float value by 10 thousand
    MKC = _MK$(_INTEGER64, CVal)
END FUNCTION
Note: The _FLOAT currency amount must be multiplied by 10000 before it is converted to the ASCII string value.

CVC

PDS also had the CVC function to convert MKC$ currency string values back to currency amounts. QB64 can use _CV with _INTEGER64 to convert those 8 byte values back to _FLOAT currency values. The procedure gets the currency string from a file: 

SCREEN 12
DIM currency AS STRING * 8
OPEN "Currency.bin" FOR BINARY AS #1 'binary file with MKC$ values created by PDS or VB
GET #1, , currency
CLOSE #1

_PRINTSTRING (1, 10), "[" + currency + "]" 'show ASCII string value from file

_PRINTSTRING (1, 30), STR$(CVC##(currency))

END

FUNCTION CVC## (CurrStr AS STRING) 'converts currency string to a _FLOAT currency amount
    DIM CV AS _INTEGER64
    CV = _CV(_INTEGER64, CurrStr)
    CVC = CV / 10000 '                   divide by 10 thousand
END FUNCTION
Note: The _FLOAT currency amount must be divided by 10000 to create up to 4 decimal point places.

PUT

Currency values can be PUT directly into BINARY or RANDOM files using an _INTEGER64 variable value. 

DIM curr AS _INTEGER64, currency AS _FLOAT

currency = 9876.543
curr = currency * 10000 ' multiply currency value by 10000

OPEN "currency.bin" FOR BINARY AS #1 ' a binary file to hold PDS currency values
PUT #1, , curr
CLOSE #1

END

GET

When currency values are PUT directly into a BINARY or RANDOM file, _INTEGER64 can GET them directly. Then divide by 10 ^ 4: 

DIM curr AS _INTEGER64, currency AS _FLOAT
OPEN "currency.bin" FOR BINARY AS #1 ' any binary file holding PDS currency values
GET #1, , curr
CLOSE #1

currency = curr / 10000 ' use any floating decimal point type within currency range

PRINT currency

END
Note: The currency value can be any SINGLE, DOUBLE or _FLOAT floating decimal point value that will hold the range of values.


(Return to Table of Contents)

DIR$

Not to be confused with QB64's _DIR$ function.

This PDS(7.1) derived DIR$ function returns a filename or a list when more than one exist. The file spec can use a path and/or wildcards. 

FOR i = 1 TO 2
    PRINT
    LINE INPUT "Enter a file spec: ", spec$
    file$ = DIR$(spec$) 'use a file spec ONCE to find the last file name listed
    PRINT DIRCount%, file$, 'function can return the file count using SHARED variable
    IF DIRCount% > 1 THEN
        DO
            K$ = INPUT$(1)
            file$ = DIR$("") 'use an empty string parameter to return a list of files!
            PRINT file$,
        LOOP UNTIL LEN(file$) = 0 'file list ends with an empty string
    END IF
NEXT

END

FUNCTION DIR$ (spec$)
    CONST TmpFile$ = "DIR$INF0.INF", ListMAX% = 500 'change maximum to suit your needs
    SHARED DIRCount% 'returns file count if desired. MAY conflict with user's existing code
    STATIC Ready%, Index%, DirList$()
    IF NOT Ready% THEN REDIM DirList$(ListMAX%): Ready% = -1 'DIM array first use
    IF spec$ > "" THEN 'get file names when a spec is given
        SHELL _HIDE "DIR " + spec$ + " /b > " + TmpFile$
        Index% = 0: DirList$(Index%) = "": ff% = FREEFILE
        OPEN TmpFile$ FOR APPEND AS #ff%
        size& = LOF(ff%)
        CLOSE #ff%
        IF size& = 0 THEN KILL TmpFile$: EXIT FUNCTION
        OPEN TmpFile$ FOR INPUT AS #ff%
        DO WHILE NOT EOF(ff%) AND Index% < ListMAX%
            Index% = Index% + 1
            LINE INPUT #ff%, DirList$(Index%)
        LOOP
        DIRCount% = Index% 'SHARED variable can return the file count
        CLOSE #ff%
        KILL TmpFile$
    ELSE IF Index% > 0 THEN Index% = Index% - 1 'no spec sends next file name
    END IF
    DIR$ = DirList$(Index%)
END FUNCTION
Code by Ted Weissgerber
Explanation: The function will verify that a file exists (even if it is empty) by returning it's name or it returns an empty string if no file exists. It can return a list of file names by using an empty string parameter("") after sending a wildcard spec to get the first file name. The number of file names found is returned by using the SHARED variable, DIRCount%. Unlike the PDS DIR$ function, it MUST use an empty string parameter until QB64 supports optional parameters! The function does NOT delete empty files.


(Return to Table of Contents)


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