transmitting the value of a variable to a new variable

[Seyed Mahmoud Hosseinniakani]

Hi users,

Considering the example in below, I wonder if it would be possible to generate a new variable (date2) and transmit the value of date to the new variable for each observation (ISIN) based on ISIN2. I am not sure which sort of commands help to get such a result as shown in table 1.

I would be grateful if someone could help me.

Example
input str12(ISIN ISIN2) int date
"GB0001771426" "GB0001771426" 20463
"GB0001771426" "NL0009739416" 20494
"GB0001771426" "SE0000103814" 20521
"GB0001771426" "PLTAURN00011" 20489
"GB0001771426"
"GB0001771426"
"GB0001771426"
"GB0001771426"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"NL0009739416"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"PLTAURN00011"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"
"SE0000103814"

Table1

ISIN	New variable (date2)	ISIN2	Date
GB0001771426	01/10/2016	GB0001771426	01/10/2016
GB0001771426	01/10/2016	NL0009739416	02/10/2016
GB0001771426	01/10/2016	SE0000103814	03/08/2016
GB0001771426	01/10/2016	PLTAURN00011	02/05/2016
GB0001771426	01/10/2016
GB0001771426	01/10/2016
GB0001771426	01/10/2016
GB0001771426	01/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
NL0009739416	02/10/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
PLTAURN00011	02/05/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016
SE0000103814	03/08/2016

[Clyde Schechter]

This will work:

* Example generated by -dataex-. To install: ssc install dataex
clear
input str14(ISIN ISIN2) int date
`""GB0001771426""' `""GB0001771426""' 20463
`""GB0001771426""' `""NL0009739416""' 20494
`""GB0001771426""' `""SE0000103814""' 20521
`""GB0001771426""' `""PLTAURN00011""' 20489
`""GB0001771426""' ""                     .
`""GB0001771426""' ""                     .
`""GB0001771426""' ""                     .
`""GB0001771426""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""NL0009739416""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""PLTAURN00011""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
`""SE0000103814""' ""                     .
end
format date %td

preserve
keep ISIN2 date
drop if missing(date)
tempfile isin2file
rename ISIN2 ISIN
rename date date2
save `isin2file'

restore
merge m:1 ISIN using `isin2file'
order date2, after(ISIN)

Your -input- command is not compatible with the data you show underneath it, and it was not possible to import your example from there. I don't know whether that -input- command came from a -dataex- output that got mangled through subsequent editing, or whether you just tried to write some code that more or less resembled real -dataex- output, but wasn't. Either way, you shouldn't do that. Just use -dataex- on your Stata data set: it never produces unusable results. If you didn't actually have your data imported into Stata yet, then it was premature to ask for help with code. Code and data have to fit like a hand and glove. It is a waste of time to write code for a non-existent data set: the actual data will often have features that break the code.

In the future, when showing data examples, please use the -dataex- command to do so. If you are running version 15.1 or a fully updated version 14.2, it is already part of your official Stata installation. If not, run -ssc install dataex- to get it. Either way, run -help dataex- to read the simple instructions for using it. -dataex- will save you time; it is easier and quicker than typing out tables. It includes complete information about aspects of the data that are often critical to answering your question but cannot be seen from tabular displays or screenshots. It also makes it possible for those who want to help you to create a faithful representation of your example to try out their code, which in turn makes it more likely that their answer will actually work in your data.

When asking for help with code, always show example data. When showing example data, always use -dataex-.

[Seyed Mahmoud Hosseinniakani]

Hi Clyde,
Thanks for the help. I used dataex but the then I edited here. It was my mistake that I edited the data. The commands work well.
Kind regards,
Mahmoud