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reading_20and_20writing_20arrays_20in_20files

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reading_20and_20writing_20arrays_20in_20files [2018/03/31 13:19] – external edit 127.0.0.1reading_20and_20writing_20arrays_20in_20files [2024/01/05 00:21] (current) – external edit 127.0.0.1
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 //by Jon Ripley, May 2011//\\ \\ //Alternative method added by Steve Drain, Oct 2013//\\ \\  BBC BASIC for Windows does not provide a simple method of writing arrays to a file and reading them back again, doing so traditionally requires looping through the array and saving each separate item individually.\\ \\  The PROC_ReadArray and PROC_WriteArray routines below provide equivalents to PRINT# and INPUT# for arrays and are faster than the traditional method in most cases.\\ \\  //by Jon Ripley, May 2011//\\ \\ //Alternative method added by Steve Drain, Oct 2013//\\ \\  BBC BASIC for Windows does not provide a simple method of writing arrays to a file and reading them back again, doing so traditionally requires looping through the array and saving each separate item individually.\\ \\  The PROC_ReadArray and PROC_WriteArray routines below provide equivalents to PRINT# and INPUT# for arrays and are faster than the traditional method in most cases.\\ \\ 
 +<code bb4w>
         PROC_WriteArray(fileHandle%, ^array())         PROC_WriteArray(fileHandle%, ^array())
         PROC_ReadArray(fileHandle%, ^array())         PROC_ReadArray(fileHandle%, ^array())
 +</code>
 \\  When reading and writing arrays you must prefix the array variable name with the address of operator, the **^** symbol, this allows us to pass all types of array to a single routine rather than requiring a separate routine for each.\\ \\ **PROC_WriteArray** writes the contents of an array to the file specified by fileHandle%.\\ \\  \\  When reading and writing arrays you must prefix the array variable name with the address of operator, the **^** symbol, this allows us to pass all types of array to a single routine rather than requiring a separate routine for each.\\ \\ **PROC_WriteArray** writes the contents of an array to the file specified by fileHandle%.\\ \\ 
 +<code bb4w>
         DIM array(9, 9, 9, 9)         DIM array(9, 9, 9, 9)
         REM Initialise array         REM Initialise array
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         PROC_WriteArray(fileHandle%, ^array())         PROC_WriteArray(fileHandle%, ^array())
         CLOSE#fileHandle%         CLOSE#fileHandle%
 +</code>
 \\ **PROC_ReadArray** reads data from the file specified by fileHandle% and stores it in the specified array.\\ \\  \\ **PROC_ReadArray** reads data from the file specified by fileHandle% and stores it in the specified array.\\ \\ 
 +<code bb4w>
         DIM array(1000, 10)         DIM array(1000, 10)
         fileHandle% = OPENIN("data.dat")         fileHandle% = OPENIN("data.dat")
         PROC_ReadArray(fileHandle%, ^array())         PROC_ReadArray(fileHandle%, ^array())
         CLOSE#fileHandle%         CLOSE#fileHandle%
 +</code>
 \\  For more information about **PROC_SwapMemory** see [[/swapping%20the%20contents%20of%20two%20areas%20of%20memory|swapping the contents of two areas of memory]].\\ \\  The full code for PROC_ReadArray, PROC_WriteArray and PROC_SwapMemory is as follows:\\ \\  \\  For more information about **PROC_SwapMemory** see [[/swapping%20the%20contents%20of%20two%20areas%20of%20memory|swapping the contents of two areas of memory]].\\ \\  The full code for PROC_ReadArray, PROC_WriteArray and PROC_SwapMemory is as follows:\\ \\ 
 +<code bb4w>
         DEF PROC_WriteArray(file%, parr%):LOCAL write%:write%=TRUE         DEF PROC_WriteArray(file%, parr%):LOCAL write%:write%=TRUE
         DEF PROC_ReadArray(file%, parr%):LOCAL write%         DEF PROC_ReadArray(file%, parr%):LOCAL write%
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         ENDPROC         ENDPROC
        
 +</code>
 \\  Thanks to Richard Russell for the SwapMemory function.\\ \\  Thanks to Richard Russell for the SwapMemory function.\\
 ---- ----
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   * a string target array must be empty   * a string target array must be empty
 \\  \\ 
 +<code bb4w>
         DEF PROC_WriteArray(file%,pntr%)         DEF PROC_WriteArray(file%,pntr%)
         LOCAL type%,size%,numb%,temp%         LOCAL type%,size%,numb%,temp%
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         pntr%=temp%         pntr%=temp%
         ENDPROC         ENDPROC
 +</code>
reading_20and_20writing_20arrays_20in_20files.1522502376.txt.gz · Last modified: 2024/01/05 00:16 (external edit)