topic Re: choosing observations based on first occurence of a varaiable in SAS Programming https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686676#M208418 <PRE><CODE class=" language-sas">data want; set have; by id; retain write; if first.id then write = 1; if write then output; if flag then write = 0; run;</CODE></PRE> <P>This makes use of the fact that 0 and missing are considered false, and any other non-missing value true.</P> Fri, 25 Sep 2020 12:54:11 GMT Kurt_Bremser 2020-09-25T12:54:11Z choosing observations based on first occurence of a varaiable https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686672#M208416 <P>Hi all,</P><P>&nbsp;</P><P>I have a dataset as:</P><P>Id.no&nbsp; Number&nbsp; Flag</P><P>101 &nbsp; &nbsp;&nbsp; 543 &nbsp; &nbsp; &nbsp; &nbsp; 0</P><P>101 &nbsp; &nbsp;&nbsp; 657 &nbsp; &nbsp; &nbsp; &nbsp; 0</P><P>101 &nbsp; &nbsp;&nbsp; 723 &nbsp; &nbsp; &nbsp; &nbsp; 1</P><P>101 &nbsp; &nbsp;&nbsp; 123 &nbsp; &nbsp; &nbsp; &nbsp; 0</P><P>101 &nbsp; &nbsp; &nbsp; 432 &nbsp; &nbsp; &nbsp;&nbsp; 0</P><P>102 &nbsp; &nbsp; &nbsp;&nbsp; 564 &nbsp; &nbsp; &nbsp;&nbsp; 0</P><P>102 &nbsp; &nbsp; &nbsp;&nbsp; 634 &nbsp; &nbsp; &nbsp; 1</P><P>102 &nbsp; &nbsp; &nbsp; 327 &nbsp; &nbsp; &nbsp;&nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 765 &nbsp; &nbsp; &nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp; &nbsp; 567 &nbsp; &nbsp;&nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 908 &nbsp; &nbsp; &nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 432 &nbsp; &nbsp; &nbsp; 1</P><P>103 &nbsp; &nbsp; &nbsp; 231 &nbsp; &nbsp; &nbsp;&nbsp; 0</P><P>Can I get the observations upto the first occurrence of flag variable as '1' for each id no? I mean the output dataset as:</P><P>Id.no&nbsp; Number&nbsp; Flag</P><P>101 &nbsp; &nbsp;&nbsp; 543 &nbsp; &nbsp; &nbsp; &nbsp; 0</P><P>101 &nbsp; &nbsp;&nbsp; 657 &nbsp; &nbsp; &nbsp; &nbsp; 0</P><P>101 &nbsp; &nbsp;&nbsp; 723 &nbsp; &nbsp; &nbsp; &nbsp; 1</P><P>102 &nbsp; &nbsp; &nbsp;&nbsp; 564 &nbsp; &nbsp; &nbsp;&nbsp; 0</P><P>102 &nbsp; &nbsp; &nbsp;&nbsp; 634 &nbsp; &nbsp; &nbsp; 1</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 765 &nbsp; &nbsp; &nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp; &nbsp; 567 &nbsp; &nbsp;&nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 908 &nbsp; &nbsp; &nbsp; 0</P><P>103 &nbsp; &nbsp; &nbsp;&nbsp; 432 &nbsp; &nbsp; &nbsp; 1</P><P>&nbsp;</P><P>Please help me out for this . Thank you</P> Fri, 25 Sep 2020 12:39:04 GMT https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686672#M208416 AKHILA 2020-09-25T12:39:04Z Re: choosing observations based on first occurence of a varaiable https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686676#M208418 <PRE><CODE class=" language-sas">data want; set have; by id; retain write; if first.id then write = 1; if write then output; if flag then write = 0; run;</CODE></PRE> <P>This makes use of the fact that 0 and missing are considered false, and any other non-missing value true.</P> Fri, 25 Sep 2020 12:54:11 GMT https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686676#M208418 Kurt_Bremser 2020-09-25T12:54:11Z Re: choosing observations based on first occurence of a varaiable https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686680#M208419 <P>Please take note that a variable does not "occur". It's either present in a dataset (and therefore the data step that reads it) or not.&nbsp;<EM>Values</EM>&nbsp;occur.</P> Fri, 25 Sep 2020 12:57:07 GMT https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686680#M208419 Kurt_Bremser 2020-09-25T12:57:07Z Re: choosing observations based on first occurence of a varaiable https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686688#M208423 <PRE><CODE class=" language-sas"> data have; input Id_no Number Flag; cards; 101 543 0 101 657 0 101 723 1 101 123 0 101 432 0 102 564 0 102 634 1 102 327 0 103 765 0 103 567 0 103 908 0 103 432 1 103 231 0 ; data want; do until(last.id_no); set have; by id_no; if _n_ then output; if flag then _n_=0; end; run; proc print noobs;run;</CODE></PRE> <DIV class="branch"> <DIV> <DIV align="center"> <TABLE class="table" summary="Procedure Print: Data Set WORK.WANT" frame="box" rules="all" cellspacing="0" cellpadding="5"> <THEAD> <TR> <TH class="r header" scope="col">Id_no</TH> <TH class="r header" scope="col">Number</TH> <TH class="r header" scope="col">Flag</TH> </TR> </THEAD> <TBODY> <TR> <TD class="r data">101</TD> <TD class="r data">543</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">101</TD> <TD class="r data">657</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">101</TD> <TD class="r data">723</TD> <TD class="r data">1</TD> </TR> <TR> <TD class="r data">102</TD> <TD class="r data">564</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">102</TD> <TD class="r data">634</TD> <TD class="r data">1</TD> </TR> <TR> <TD class="r data">103</TD> <TD class="r data">765</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">103</TD> <TD class="r data">567</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">103</TD> <TD class="r data">908</TD> <TD class="r data">0</TD> </TR> <TR> <TD class="r data">103</TD> <TD class="r data">432</TD> <TD class="r data">1</TD> </TR> </TBODY> </TABLE> </DIV> </DIV> </DIV> Fri, 25 Sep 2020 13:25:53 GMT https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686688#M208423 novinosrin 2020-09-25T13:25:53Z Re: choosing observations based on first occurence of a varaiable https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686699#M208425 Thank you so much!! Fri, 25 Sep 2020 14:13:12 GMT https://communities.sas.com/t5/SAS-Programming/choosing-observations-based-on-first-occurence-of-a-varaiable/m-p/686699#M208425 AKHILA 2020-09-25T14:13:12Z