writing multiple-dimensioned arrays to file

[John Montenigro]

I use the following function for single dimensioned arrays.

Function WriteFil(Ary() As String, ByVal OutFil As String) As Long
'output array to file  - is this only good for a one-dim array
   Local hFile As Long

   If IsFile(OutFil) Then
      Kill OutFil
   End If

   hFile = FreeFile
   Open OutFil For Output As #hFile
   Print #hFile, Ary()      '  [B]<----------[/B]
   Close #hFile
End Function

I may have messed up something else, but I can't seem to get
"PRINT #hFile, Ary()" to work on a multi-dimensioned array. Is there some special syntax I've missed?


In the meantime, I've had to write a second routine that goes thru the array line-by-line...

Yes, I went thru the Helpfile, even tried JOIN$, but I need TABs between fields and CRLFs between records...

I'd love to see "JOIN$" or "PRINT #file, Ary()" syntax to do so.

[Guy Dombrowski]

Why do you not use the Binary mode ?

[John Montenigro]

Not sure what you're suggesting.

   Open OutFil For Binary As #hFile
   Put$ #hFile, Join$(Ary(), $CrLf)
   Close #hFile

but that puts a CRLF after each field, not record.

[Paul Dixon]

John,
just use the PUT statement as shown in the helpfile:

http://www.powerbasic.com/support/help/pbcc/put_statement.htm

Binary files:
PUT [#] fNum&, [RecPos], Arr()
..
When PUT is used on a binary file, the entire array specified by Arr() is written to the file.

[John Montenigro]

Thanks Paul, but it ain't good...

   Open OutFil For Binary As #hFile
   Put #hFile, 1,Ary()

I'm getting all kinds of extraneous characters in the file between records and where line-end chars should be...

[Paul Dixon]

John,
it's intended to be used like this:

'PBCC5 program
FUNCTION PBMAIN() AS LONG

DIM a&(10,10)
FOR r& = 0 TO 10
    FOR c& = 0 TO 10
        a&(r&,c&)= r&*100 + c&
    NEXT
NEXT

PRINT "Before"; a&(5,7)

OPEN "arrayfile" FOR BINARY AS #1
PUT #1,,a&()
CLOSE
'clear the array
FOR r& = 0 TO 10
    FOR c& = 0 TO 10
        a&(r&,c&)= 0
    NEXT
NEXT

PRINT "after clear"; a&(5,7)

OPEN "arrayfile" FOR BINARY AS #1
GET #1,,a&()
CLOSE

PRINT "After restore from file"; a&(5,7)

WAITKEY$

END FUNCTION

Perhaps you're using it differently?

Paul.

[Neil Croft]

John, What are you wanting to do with the resultant file?

If you just want to read it back into another program of your making then

open "file" for binary as hfile
put# hfile,,array()
close

will dump the array to disk and

get# hfile,,array()

will load it back.

If you want it in human readable form then you'll need to do something else.

[Gösta H. Lovgren-2]

[quote=John Montenigro;320130]I use the following function for single dimensioned arrays.

Function WriteFil(Ary() As String, ByVal OutFil As String) As Long
'output array to file  - is this only good for a one-dim array
   Local hFile As Long
 
   If IsFile(OutFil) Then '[COLOR=red]<<< Not necessary. Open for Output overwrites[/COLOR]
      Kill OutFil             [COLOR=red]'       if it exists.[/COLOR]
   End If
 
   hFile = FreeFile
   Open OutFil For Output As #hFile
   Print #hFile, Ary()      '  [B]<----------[/B]
   Close #hFile
End Function

The file gets overwritten when Opened for Output. Not that it has anything to do with Array writing but just to keep my hand in.

============================
Success is the ability
to go from one failure
to another
with no loss of enthusiasm.
Winston Churchill.
============================

[Dave Biggs]

This example extends Paul's 'PUT / GET' code to show the 'Print / Line Input' method too..

'PBWin program
FUNCTION PBMAIN() AS LONG
 
  DIM a$(2,5,10)
  FOR p& = 0 To 2
    FOR r& = 0 TO 5
      FOR c& = 0 TO 10
          a$(p&,r&,c&)= " Cell Value: " + format$(p&*10000 + r&*100 + c&, "000000")
      NEXT
    NEXT
  NEXT
 
  ? "Before save, a$(2,5,7): " + a$(2,5,7)
  ' Write ascii file
  OPEN "ArrayFileA" FOR OUTPUT AS #2
  PRINT #2, a$()                ' Note. When used w/ numeric values, written as ASCII text equiv values
  CLOSE #2                      '       Delimited w/ $CRLF (new line per data value)
 
 ' Write binary file
  OPEN "ArrayFileB" FOR BINARY AS #1
  PUT #1,,a$()                  ' Write entire array to file as single block
  CLOSE                         ' Dynamic string data saved in PowerBASIC packed string format
 
  GOSUB ClearArray
  ? "a$(2,5,7) after clear: " + a$(2,5,7)
 
  ' Read ascii file
  OPEN "ArrayFileA" FOR INPUT AS #2
  FileScan #2, Records To Rec&
  LINE INPUT #2, a$()           ' Assign full line of text to each array element
  CLOSE #2
  ? "After restore from A file, a$(2,5,7): " + a$(2,5,7) + $CR + str$(Rec&) + " Records"
 
  GOSUB ClearArray              ' clear the array
  ? "a$(2,5,7) after clear: " + a$(2,5,7)
 
  ' Read Bin file
  OPEN "ArrayFileB" FOR BINARY AS #1
  FileScan #1, Records To Rec&
  GET #1,,a$()                  ' With a dynamic string array, it is assumed the file was written 
  CLOSE #1                      ' in the PowerBASIC packed string format
  ? "After restore from B file, a$(2,5,7): " + a$(2,5,7) + $CR + str$(Rec&) + " Records"

 EXIT FUNCTION 
 
 ClearArray:
  FOR p& = 0 To 2
    FOR r& = 0 TO 5
      FOR c& = 0 TO 10
          a$(p&,r&,c&)= ""
      NEXT
    NEXT
  NEXT
 RETURN
 
END FUNCTION 
'------------------/
#IF 0
 
Array data is stored in column major order ([URL]http://en.wikipedia.org/wiki/Row-major_order[/URL])
 
A file data..
 Cell Value: 000000(crlf)
 Cell Value: 010000(cr..etc
 Cell Value: 020000
 Cell Value: 000100
 Cell Value: 010100
 Cell Value: 020100
 Cell Value: 000200
 Cell Value: 010200
 Cell Value: 020200
 Cell Value: 000300
 Cell Value: 010300
 Cell Value: 020300
 Cell Value: 000400
 Cell Value: 010400
 Cell Value: 020400
 Cell Value: 000500
 Cell Value: 010500
 Cell Value: 020500
 Cell Value: 000001
 Cell Value: 010001
 Cell Value: 020001
 Cell Value: 000101(crlf) etc..
 
B file data..
 Two byte 'length' is followed by the string data. e.g. '&h1300' (LSB,MSB ~ 19 chars)
 13 00  Cell Value: 000000 13 00  Cell Value: 010000 13 00 etc..
 
#ENDIF

[Michael Mattias]

ClearArray:
  FOR p& = 0 To 2
    FOR r& = 0 TO 5
      FOR c& = 0 TO 10
          a$(p&,r&,c&)= ""
      NEXT
    NEXT
  NEXT
 RETURN

==>

RESET A$()

[Dave Biggs]

> Reset a$()

Yes that's better!

[Michael Mattias]

One little potential gotcha here....

It does not matter in this demo because the array is never resized, but in this code...

' Read Bin file
  OPEN "ArrayFileB" FOR BINARY AS #1
  GET #1,,a$()

.. the array already has to be sized properly. That is, 'as written' this code will not be useful for retrieving data saved in a previous program run unless you know the number of dimensions and the number of elements in each dimension.

I did a generic save/load array to disk thing a long time ago (and I mean a LONG time ago.. like back in the MS-DOS days). Maybe I can find that and figure out if there might be a way with the newer compilers to deal with that.

MCM

[John Montenigro]

Thanks for all the options and suggestions, guys. I'm away from my development machine till Monday night, so I'll start checking code ideas then.

To answer the question about intended use: The file will be imported into a DBMS.
IF it's possible, a format that could be quickly scanned by grey-ware would be a plus.

-John

[Dave Biggs]

.. the array already has to be sized properly. That is, 'as written' this code will not be useful for retrieving data saved in a previous program run unless you know the number of dimensions and the number of elements in each dimension.

That's true. As is, the file data is saved in a linear fashon.
There would need to be information in the data itself to inform the user of more than just the number of records - which you can get with Filescan (for string arrays).

- Editted code above (#9) to show number of records retrieved from file.