MapInfo Pro Developers User Group

Hi,

I have a table with several fields, and each field needs to be set to a specific number value IF it currently has a certain number value.

That is, if any value in any field is -0.1 it needs to be changed to -0.2.

So the logic is :

if Item2 = -0.1 then set Item2 = -0.2

elseif Item2 <> -0.2

then Item2 = Item2

end if

Can any one put this into correct Mapbasic syntax?

Thanks.

If you are using MapBasic, you can create a custom function and use this in your update statement:

Function CustomIIF(ByVal fInputValue As Float, ByVal fCompareValue As Float, ByVal fOutputValue As Float) As Float

If fInputValue = fCompareValue then

CustomIIF = fOutputValue

Else

CustomIIF = fInputValue

End if

End Function

Use the function like this:

Update MYTABLE Set MYCOLUMN = CustomIFF(MYCOLUMN, -0.1, -0.2)

Here is the complete mapbasic code that will serve your purpose ... Hope this helps ....

========================================================================================================

include "mapbasic.def"

include "Icons.def"

include "Menu.def"

Declare Sub Main

Sub Main

Dim Tabname,sColName,currcolumn,cmdstr as string

Dim x,y as integer

Dim currvalue as alias

//Opening up your table

Tabname = "C:\test.tab"

open table Tabname as inputtable

//Iterating through the table

If Tableinfo(inputtable,TAB_INFO_NROWS) <> 0 then

For x = 1 to TableInfo(inputtable,TAB_INFO_NROWS)

Fetch rec x from inputtable

For y=1 to TableInfo(inputtable, TAB_INFO_NCOLS)

sColName = ColumnInfo(inputtable, "col"+str$(y), COL_INFO_NAME)

currvalue = inputtable & "." & sColName

if currvalue = "-0.1" then

Update inputtable set sColName = -0.2 where rowid = x

elseif currvalue <> "-0.1" then

Update inputtable set sColName = currvalue where rowid = x

End If

Next

Next

Else

Note "No records in the input table, pls check "

End If

End Sub

IIF() and COND() are built in functions that will be included with MapBasic 17.0.

thanks, there were some errors with field types, so i will probably just do the updates manually

Try the new IIF() or COND() function out in the current Beta. Hopefully it will suit your purpose. Since you are looking for specific Item values, I might go with a Case statement rather than an If\Then\Else. Just a suggestion.

Thx,

-Bill