From 4c333ae7b384aaa1d732f50afdadb9d50548dc6b Mon Sep 17 00:00:00 2001 From: Allan Bowe <> Date: Wed, 23 Dec 2020 00:33:59 +0000 Subject: [PATCH] feat: mp_prevobs.sas macro --- all.sas | 145 ++++++++++++++++++++++++++++++++++++++++++++ base/mp_prevobs.sas | 88 +++++++++++++++++++++++++++ 2 files changed, 233 insertions(+) create mode 100644 base/mp_prevobs.sas diff --git a/all.sas b/all.sas index 6bd5462..8151753 100644 --- a/all.sas +++ b/all.sas @@ -4066,6 +4066,93 @@ select distinct lowcase(memname) ,dttm=%sysfunc(datetime()); quit; +%mend;/** + @file + @brief Enables previous observations to be re-instated + @details Remembers the last X observations by storing them in a hash table. + Is a convenience over the use of lag() or retain, when an entire observation + needs to be restored. + + This macro will also restore automatic variables (such as _n_ and _error_). + + Example Usage: + + data example; + set sashelp.class; + calc_var=_n_*3; + * initialise hash and save from PDV ; + %mp_prevobs(INIT,history=2) + if _n_ =10 then do; + * fetch previous but 1 record; + %mp_prevobs(FETCH,-2) + put _n_= name= age= calc_var=; + * fetch previous record; + %mp_prevobs(FETCH,-1) + put _n_= name= age= calc_var=; + * reinstate current record ; + %mp_prevobs(FETCH,0) + put _n_= name= age= calc_var=; + end; + run; + + Result: + + mp_prevobs sas + + Credit is made to `data _null_` for authoring this very helpful paper: + https://www.lexjansen.com/pharmasug/2008/cc/CC08.pdf + + @param action Either FETCH a current or previous record, or INITialise. + @param record The relative (to current) position of the previous observation + to return. + @param history= The number of records to retain in the hash table. Default=5 + @param prefix= the prefix to give to the variables used to store the hash name + and index. Default=mp_prevobs + + @version 9.2 + @author Allan Bowe + +**/ + +%macro mp_prevobs(action,record,history=5,prefix=mp_prevobs +)/*/STORE SOURCE*/; +%let action=%upcase(&action); +%let prefix=%upcase(&prefix); +%let record=%eval((&record+0) * -1); + +%if &action=INIT %then %do; + + if _n_ eq 1 then do; + attrib &prefix._VAR length=$64; + dcl hash &prefix._HASH(ordered:'Y'); + &prefix._KEY=0; + &prefix._HASH.defineKey("&prefix._KEY"); + do while(1); + call vnext(&prefix._VAR); + if &prefix._VAR='' then leave; + if &prefix._VAR eq "&prefix._VAR" then continue; + else if &prefix._VAR eq "&prefix._KEY" then continue; + &prefix._HASH.defineData(&prefix._VAR); + end; + &prefix._HASH.defineDone(); + end; + /* this part has to happen before FETCHing */ + &prefix._KEY+1; + &prefix._rc=&prefix._HASH.add(); + if &prefix._rc then putlog 'adding' &prefix._rc=; + %if &history>0 %then %do; + if &prefix._key>&history+1 then + &prefix._HASH.remove(key: &prefix._KEY - &history - 1); + if &prefix._rc then putlog 'removing' &prefix._rc=; + %end; +%end; +%else %if &action=FETCH %then %do; + if &record > &prefix._key then putlog "Not enough records in &Prefix._hash yet"; + else &prefix._rc=&prefix._HASH.find(key: &prefix._KEY - &record); + if &prefix._rc then putlog &prefix._rc= " when fetching " &prefix._KEY= + "with record &record and " _n_=; +%end; + %mend;/** @file @brief Returns all children from a hierarchy table for a specified parent @@ -4667,6 +4754,64 @@ proc sql %mp_binarycopy(inloc="&inloc",outref=_webout) %end; +%mend;/** + @file mp_testwritespeedlibrary.sas + @brief Tests the write speed of a new table in a SAS library + @details Will create a new table of a certain size in an + existing SAS library. The table will have one column, + and will be subsequently deleted. + + %mp_testwritespeedlibrary( + lib=work + ,size=0.5 + ,outds=work.results + ) + + @param lib= (WORK) The library in which to create the table + @param size= (0.1) The size in GB of the table to create + @param outds= (WORK.RESULTS) The output dataset to be created. + +

Dependencies

+ @li mf_getuniquename.sas + @li mf_existds.sas + + @version 9.4 + @author Allan Bowe + +**/ + +%macro mp_testwritespeedlibrary(lib=WORK + ,outds=work.results + ,size=0.1 +)/*/STORE SOURCE*/; +%local ds start; + +/* find an unused, unique name for the new table */ +%let ds=%mf_getuniquename(); +%do %until(%mf_existds(&lib..&ds)=0); + %let ds=%mf_getuniquename(); +%end; + +%let start=%sysfunc(datetime()); + +data &lib..&ds(compress=no keep=x); + header=128*1024; + size=(1073741824/8 * &size) - header; + do x=1 to size; + output; + end; +run; + +proc sql; +drop table &lib..&ds; + +data &outds; + lib="&lib"; + start_dttm=put(&start,datetime19.); + end_dttm=put(datetime(),datetime19.); + duration_seconds=end_dttm-start_dttm; +run; + %mend;/** @file @brief Recursively scans a directory tree to get all subfolders and content diff --git a/base/mp_prevobs.sas b/base/mp_prevobs.sas new file mode 100644 index 0000000..429d4c7 --- /dev/null +++ b/base/mp_prevobs.sas @@ -0,0 +1,88 @@ +/** + @file + @brief Enables previous observations to be re-instated + @details Remembers the last X observations by storing them in a hash table. + Is a convenience over the use of lag() or retain, when an entire observation + needs to be restored. + + This macro will also restore automatic variables (such as _n_ and _error_). + + Example Usage: + + data example; + set sashelp.class; + calc_var=_n_*3; + * initialise hash and save from PDV ; + %mp_prevobs(INIT,history=2) + if _n_ =10 then do; + * fetch previous but 1 record; + %mp_prevobs(FETCH,-2) + put _n_= name= age= calc_var=; + * fetch previous record; + %mp_prevobs(FETCH,-1) + put _n_= name= age= calc_var=; + * reinstate current record ; + %mp_prevobs(FETCH,0) + put _n_= name= age= calc_var=; + end; + run; + + Result: + + mp_prevobs sas + + Credit is made to `data _null_` for authoring this very helpful paper: + https://www.lexjansen.com/pharmasug/2008/cc/CC08.pdf + + @param action Either FETCH a current or previous record, or INITialise. + @param record The relative (to current) position of the previous observation + to return. + @param history= The number of records to retain in the hash table. Default=5 + @param prefix= the prefix to give to the variables used to store the hash name + and index. Default=mp_prevobs + + @version 9.2 + @author Allan Bowe + +**/ + +%macro mp_prevobs(action,record,history=5,prefix=mp_prevobs +)/*/STORE SOURCE*/; +%let action=%upcase(&action); +%let prefix=%upcase(&prefix); +%let record=%eval((&record+0) * -1); + +%if &action=INIT %then %do; + + if _n_ eq 1 then do; + attrib &prefix._VAR length=$64; + dcl hash &prefix._HASH(ordered:'Y'); + &prefix._KEY=0; + &prefix._HASH.defineKey("&prefix._KEY"); + do while(1); + call vnext(&prefix._VAR); + if &prefix._VAR='' then leave; + if &prefix._VAR eq "&prefix._VAR" then continue; + else if &prefix._VAR eq "&prefix._KEY" then continue; + &prefix._HASH.defineData(&prefix._VAR); + end; + &prefix._HASH.defineDone(); + end; + /* this part has to happen before FETCHing */ + &prefix._KEY+1; + &prefix._rc=&prefix._HASH.add(); + if &prefix._rc then putlog 'adding' &prefix._rc=; + %if &history>0 %then %do; + if &prefix._key>&history+1 then + &prefix._HASH.remove(key: &prefix._KEY - &history - 1); + if &prefix._rc then putlog 'removing' &prefix._rc=; + %end; +%end; +%else %if &action=FETCH %then %do; + if &record > &prefix._key then putlog "Not enough records in &Prefix._hash yet"; + else &prefix._rc=&prefix._HASH.find(key: &prefix._KEY - &record); + if &prefix._rc then putlog &prefix._rc= " when fetching " &prefix._KEY= + "with record &record and " _n_=; +%end; + +%mend; \ No newline at end of file