How To: Delete columns of data

[Chris Heidecker]

I think you should not use @pData, just pData should be enough.
You’re not using it to return the data but are modifying by splitting but not combining the data.

regards,
Chris Heidecker

Op 5 sep. 2014, om 20:37 heeft Michael Doub <mikedoub at gmail.com> het volgende geschreven:

> just to complete your library, here is a function that will extract the listed column in the order that you 
> specify but it does not modify the original data.
> 
> -= Mike
> 
> 
> 
> function extractColumns @pData,pColsToReturn,pDelim
>  -- Extract specified columns from a table in order
>  -- Syntax: extractColumns <data>,<cols>[,<delim>]
>  --     data: Specifies the data to parse.
>  --     cols: A comma separated list of columns or column ranges to be returned in order
>  --         for example "2,7,5"
>  --         or a accending column range: "3-5"
>  --         of a decending column range: "5-3"
>  --         or a combination "2,4-5,7,11-9"
>  --     delim: Optional column separator for example "," or "|"
>  --         if unspecified, defaults to tab.
>  -- based on a handler by Hugh Senior and Peter M. Brigham, Use-LC list
> 
>  -- requires getItem()
> 
>  if pColsToReturn = empty then return pData
>  repeat for each item pCol in pColsToReturn
>     if "-" is in pCol then 
>        put getItem(pCol,1,"-") into firstColNbr
>        put getItem(pCol,2,"-") into lastColNbr
>        if firstColNbr < lastColNbr then
>           repeat with i = firstColNbr to lastColNbr
>              put i & comma after pColsToReturnExpanded
>           end repeat
>        else
>           repeat with i = firstColNbr down to lastColNbr
>              put i & comma after pColsToReturnExpanded
>           end repeat
>        end if
>     else
>        put pCol & comma after pColsToReturnExpanded
>     end if
>  end repeat
>  put char 1 to -2 of pColsToReturnExpanded into pColsToReturn
>  if pDelim = empty then put tab into pDelim
>  set the columnDelimiter to pDelim
>  split pData by column
>  put item 2 of extents(pData) into tMax
>  repeat for each item n in pColsToReturn
>        add 1 to x
>        put pData[n] into rData[x]
>  end repeat
>  combine rData by column
> return rData
> end extractColumns
> 
> 
> On Sep 5, 2014, at 1:51 PM, Michael Doub <mikedoub at gmail.com> wrote:
> 
>> Here is an even more general version:
>> 
>> function deleteColumns pData,pColsToDelete,pDelim
>> -- delete specified columns from a table
>> -- Syntax: deleteColumns <data>,<cols>[,<delim>]
>> --     data: Specifies the data to parse.
>> --     cols: A comma separated list of columns or column ranges to be removed,
>> --         for example "2,5,7"
>> --         or a column range: "3-5"
>> --         or a combination "2,4-5,7,9-11,"
>> --     delim: Optional column separator for example "," or "|"
>> --         if unspecified, defaults to tab.
>> -- based on a handler by Hugh Senior and Peter M. Brigham, Use-LC list
>> 
>> -- requires getItem()
>> 
>> if pColsToDelete = empty then return pData
>> repeat for each item pCol in pColsToDelete
>>    if "-" is in pCol then 
>>       put getItem(pCol,1,"-") into firstColNbr
>>       put getItem(pCol,2,"-") into lastColNbr
>>       repeat with i = firstColNbr to lastColNbr
>>          put i & comma after pColsToDeleteExpanded
>>       end repeat
>>    else
>>       put pCol & comma after pColsToDeleteExpanded
>>    end if
>> end repeat
>> put char 1 to -2 of pColsToDeleteExpanded into pColsToDelete
>> if pDelim = empty then put tab into pDelim
>> set the columnDelimiter to pDelim
>> split pData by column
>> put item 2 of extents(pData) into tMax
>> repeat with n=1 to tMax
>>    if n is NOT among the items of pColsToDelete then
>>       add 1 to x
>>       put pData[n] into pData[x]
>>    end if
>> end repeat
>> repeat with n=x+1 to tMax
>>    delete local pData[n]
>> end repeat
>> combine pData by column
>> return pData
>> end deleteColumns
>> 
>> function getItem tList,tIndex,tDelim
>> -- returns item # tIndex of tList, given itemdelimiter = tDelim
>> -- could just "get item tIndex of tList" in the calling handler but
>> --    then have to set and restore the itemDelimiter, so this is less hassle
>> -- defaults to tDelim = comma
>> 
>> if tDelim = empty then put comma into tDelim
>> set the itemdelimiter to tDelim
>> return item tIndex of tList
>> end getItem
>> 
>> 
>> 
>> On Sep 5, 2014, at 10:58 AM, Peter M. Brigham <pmbrig at gmail.com> wrote:
>> 
>>> Peter M. Brigham
>> 
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