Re: st: Manipulation of string variable using -regexm-

["STOLOWY, Herve" <stolowy@hec.fr>]

Dear Nick:

After

gen var_star = (`end' == "*") + 2 * (`end' == "*.") + 3 * (`end' ="*+")

I get an error message:

unknown function ()

Best regards

Hervé


On Sat, Oct 12, 2013 at 12:25 AM, Nick Cox <njcoxstata@gmail.com> wrote:
> Note also other solutions such as
>
> local end substr(CurrRtg, 2, .)
> gen var_star = (`end' == "*") + 2 * (`end' == "*.") + 3 * (`end' ="*+")
> assert `end' == "" if var_star == 0
>
> Nick
> njcoxstata@gmail.com
>
>
> On 11 October 2013 21:59, Federico Belotti <f.belotti@gmail.com> wrote:
>> Dear Herve
>>
>> my suggestion is to use the command -screening-, a Stata's user-written string variables exploring and recoding tool.
>> You need to search and install it using
>>
>> findit screening
>>
>> Once installed, the syntax you are looking for to obtain a new numeric variable equal to 0 if not star, 1 if only *, 2 if *- and 3 if *+ is the following
>>
>> screening, source(CurrRtg, upper) key(end "\*" end "\*-" end "\*\+" end "[A-Z]") new(mark, numeric) recode(1 "1" 2 "2" 3 "3" 4 "0")
>>
>> where
>>
>>         1) the option -source()- specifies the source variable that have to be recoded (note the suboption -upper- which allows to perform a case-insensitive match (uppercase));
>>         2) the option -key()- specifies the keywords you are looking for (in this case represented by regular expressions);
>>         3) the option -new()- specifies the name of the new variable to be created (in this case, I called it "mark". Note the suboption -numeric- that allows to get the newly created variable as a numeric variable);
>>         4) the option -recode()- specifies the user-defined coding scheme following the keywords order.
>>
>> See -help screening- for more details.
>>
>> Hope this helps.
>> Federico
>>
>>
>> On Oct 11, 2013, at 6:40 PM, STOLOWY, Herve wrote:
>>
>>> Dear Statalisters:
>>>
>>> Using Stata 12.1, I want to extract a portion of a string variable using
>>> regular expressions, i.e. -regexs- and -regexm-.
>>>
>>> My string variable has different possible values. Example:
>>>
>>> A
>>> A *
>>> A *-
>>> A *+
>>> B
>>> B *
>>> B *-
>>> B *+
>>> etc.
>>>
>>> I would like to get a variable with the content filled with the * or *- or
>>> *+ or with this type of coding:
>>>
>>> 0 if not star
>>> 1 if only *
>>> 2 if *-
>>> 3 if *+
>>>
>>> The * or *- or *+ always appear at the end on the value.
>>>
>>> I tried the following syntax:
>>>
>>> gen var_star =3D regexs(0) if(regexm(CurrRtg, "\*" "\*+" "\*-"))
>>>
>>> Unfortunately, I get a * in all cases there is a * included in the value,
>>> but I do not get the *- or *+.
>>>
>>> I have difficulties with the syntax of -regexm-.
>>>
>>> There is maybe another way to get the same result.
>>>
>>> Best regards
>>>
>>> Herve Stolowy
>>> *
>>> *   For searches and help try:
>>> *   http://www.stata.com/help.cgi?search
>>> *   http://www.stata.com/support/faqs/resources/statalist-faq/
>>> *   http://www.ats.ucla.edu/stat/stata/
>>
>> --
>> Federico Belotti, PhD
>> Research Fellow
>> Centre for Economics and International Studies
>> University of Rome Tor Vergata
>> tel/fax: +39 06 7259 5627
>> e-mail: federico.belotti@uniroma2.it
>> web: http://www.econometrics.it
>>
>>
>> *
>> *   For searches and help try:
>> *   http://www.stata.com/help.cgi?search
>> *   http://www.stata.com/support/faqs/resources/statalist-faq/
>> *   http://www.ats.ucla.edu/stat/stata/
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/faqs/resources/statalist-faq/
> *   http://www.ats.ucla.edu/stat/stata/

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/