3.7 Changing value format from alphanumerical (text) into numerical
Many variables available through microdata.no contain alphanumerical values (text format). However, the command destring
can convert such values into numerical format. By default, the variable will be overwritten by the new format (a separate variable will not be created:
destring <variable/variable list> [, <options>]
If there are values containing non-numerical characters, e.g. ,
, .
, -
, nkr
, $
, then the conversion will not complete unless the
options force
or ignore()
are used.
The option force
will force the system to convert into numerical values no matter what, where values containing non-numerical characters will be given the value for missing value: sysmiss
The option ignore()
makes it possible to define which characters/symbols to be ignored during the conversion process. This could be useful for values formatted by hyphens, commas, thousands separators etc. The following example will ignore dots, commas and hyphens that occur in values for the variable var1:
destring var1, ignore('.,-')
Alphanumerical values containing commas as decimal separators ('2,1',
'10000,00' etc) may be converted directly into numerical values while
keeping the decimals. By doing so, the converted values will be using
dots as decimal separator. The option dpcomma
can be used for such
operations.
For more information on the use of destring
, e.g. overview of all
available options, use the help destring
command.