All the records within an hour of each other - sas

I have a data set that has ID, datetime + bunch of value fields.
The idea is that the records are within one hour of each other are one session. There can only be one session every 24 hours. (Time is measured from the start of the first record)
The day() approach does not work as one record can be 23:55 PM and the next one could be 12:01 AM the next day and it would be the same session.
I've added rowid and ran the following:
data testing;
set testing;
by subscriber_no;
prev_dt = lag(record_ts);
prev_row = lag(rowid);
time_from_last = intck("Second",record_ts,prev_dt);
if intck("Second",record_ts,prev_dt) > -60*60 and intck("Second",record_ts,prev_dt) < 0 then
same_session = 'yes';
else same_session = 'no';
if intck("Second",record_ts,prev_dt) > -60*60 and intck("Second",record_ts,prev_dt) < 0 then
rowid = prev_row;
else rowid = rowid;
format prev_dt datetime19.;
output;
run;
Input
ID record_TS rowid
52 17MAY2017:06:24:28 4
52 17MAY2017:07:16:12 5
91 05APR2017:07:04:55 6
91 05APR2017:07:23:37 7
91 05APR2017:08:04:52 8
91 05MAY2017:08:56:23 9
input file is sorted by ID and record TS.
The output was
ID record_TS rowid prev_dt prev_row time_from_last same_session
52 17MAY2017:06:24:28 4 28APR2017:08:51:25 3 -1632783 no
52 17MAY2017:07:16:12 4 17MAY2017:06:24:28 4 -3104 yes
91 05APR2017:07:04:55 6 17MAY2017:07:16:12 5 3629477 no
91 05APR2017:07:23:37 6 05APR2017:07:04:55 6 -1122 yes
91 05APR2017:08:04:52 7 05APR2017:07:23:37 7 -2475 yes This needs to be 6
91 05MAY2017:08:56:23 9 05APR2017:08:04:52 8 -2595091 no
Second row from the bottom - rowid comes out 7, while I need it to come be 6.
Basically I need to change to the current rowid saved before the script moves to assess the next one.
Thank you
Ben
I've achieved what I needed with
proc sql;
create table testing2 as
select distinct t1.*, min(t2.record_TS) format datetime19. as from_time, max(t2.record_TS) format datetime19. as to_time
from testing t1
join testing t2 on t1.id_val= t2.id_val
and intck("Second",t1.record_ts,t2.record_ts) between -3600 and 3600
group by t1.id_val, t1.record_ts
order by t1.id_val, t1.record_ts
;
quit;
But I'm still wondering if there is a way to commit changes to current row before moving to assess the next row.

I think your logic is just:
Grab record_TS datetime of the first record for each ID
For subsequent records, if their record_TS is within an hour of the first record's, recode it to be the same rowID as first record.
If that's the case, you can use RETAIN to keep track of the first record_TS and rowID for each ID. This should be easier than lag(), and allows there to be multiple records in a single session. Below seems to work:
data have;
input ID record_TS datetime. rowid;
format record_TS datetime.;
cards;
52 17MAY2017:06:24:28 4
52 17MAY2017:07:16:12 5
91 05APR2017:07:04:55 6
91 05APR2017:07:23:37 7
91 05APR2017:08:04:52 8
91 05MAY2017:08:56:23 9
;
run;
data want;
set have;
by ID Record_TS;
retain SessionStart SessionRowID;
if first.ID then do;
SessionStart=Record_TS;
SessionRowID=RowID;
end;
else if (record_TS-SessionStart)<(60*60) then RowID=SessionRowID;
drop SessionStart SessionRowID;
run;
Outputs:
ID record_TS rowid
52 17MAY17:06:24:28 4
52 17MAY17:07:16:12 4
91 05APR17:07:04:55 6
91 05APR17:07:23:37 6
91 05APR17:08:04:52 6
91 05MAY17:08:56:23 9

Related

How to add or delete a blank column in SAS System?

This is my code:
DATA sales;
INFILE 'D:\Users\...\Desktop\Onions.dat';
INPUT VisitingTeam $ 1-20 ConcessionSales 21-24 BleacherSales 25-28
OurHits 29-31 TheirHits 32-34 OurRuns 35-37 TheirRuns 38-40;
PROC PRINT DATA = sales;
TITLE 'SAS Data Set Sales';
RUN;
This is the data, but the spacing may be incorrect.
Columbia Peaches 35 67 1 10 2 1
Plains Peanuts 210 . 2 5 0 2
Gilroy Garlics 151035 12 11 7 6
Sacramento Tomatoes 124 85 15 4 9 1
;
I need to add or delete a blank column at the 19th
column. Can someone help?
Just open the dataset and then look at what the variable name is. Then do:
Data Want (drop=varible_name_you_are_dropping); /*This is your output dataset*/
Set have; /*this is your dataset you have*/
Run;

Select median value per time range

I need to select a median value for each id, in each age range. So in the following table, for id = 1, in age_range of 6 months, I need to select value for row 2. Basically, I need to create a column per id where only median for each range is selected.
id wt age_range
1 22 6
1 23 6
1 24 6
2 25 12
2 24 12
2 44 18
If I understand correctly, you're looking to make a new column where for each id and age_range you have the median value for comparison. You could do this in base SAS by using proc means to output the medians and then merge it back to the original dataset. However proc sql will do this all in one step and to easily name your new column.
proc sql data;
create table want as
select id, wt, age_range, median(wt) as median_wt
from have
group by id, age_range;
quit;
id wt age_range median_wt
1 24 6 23
1 22 6 23
1 23 6 23
2 24 12 24.5
2 25 12 24.5
2 44 18 44

SAS - group individual observations

Sorry I'm new to a lot of the features of SAS - I've only been using for a couple months, mostly for survey data analysis but now I'm working with a dataset which has individual level data for a cross-over study. It's in the form: ID treatment period measure1 measure2 ....
What I want to do is be able to group these individuals by their treatment group and then output a variable with a group average for measure 1 and measure 2 and another variable with the count of observations in each group.
ie
ID trt per m1 m2
1 1 1 101 75
1 2 2 135 89
2 1 1 103 77
2 2 2 140 87
3 2 1 134 79
3 1 2 140 80
4 2 1 156 98
4 1 2 104 78
what I want is the data in the form:
group a = where trt=1 & per=1
group b = where trt=2 & per=2
group c = where trt=2 & per=1
group d = where trt=1 & per=2
trtgrp avg_m1 avg_m2 n
A 102 76 2
B ... ... ...
C
D
Thank you for the help.
/Creating Sample dataset/
data test;
infile datalines dlm=" ";
input ID : 8.
trt : 8.
per : 8.
m1 : 8.
m2 : 8.;
put ID=;
datalines;
1 1 1 101 75
1 2 2 135 89
2 1 1 103 77
2 2 2 140 87
3 2 1 134 79
3 1 2 140 80
4 2 1 156 98
4 1 2 104 78
;
run;
/Using proc summary to summarize trt and per/
Variables(dimensions) on which you want to summarize would go into class
Variables(measures) for which you want to have average would go into var
Since you want to have produce average so you will have to write mean as the desired statistics.
Read more about proc summary here
http://support.sas.com/documentation/cdl/en/proc/61895/HTML/default/viewer.htm#a002473735.htm
and here
http://web.utk.edu/sas/OnlineTutor/1.2/en/60476/m41/m41_19.htm
proc summary data=test nway;
class trt per;
var m1 m2;
output out=final(drop= _type_)
mean=;
run;
The alternative method uses PROC SQL, the advantage being that it makes use of plain-English syntax, so the concept of a group in your question is maintained in the syntax:
PROC SQL;
CREATE TABLE final AS
SELECT
trt,
per,
avg(m1) AS avg_m1,
avg(m2) AS avg_m2,
count(*) AS n
FROM
test
GROUP BY trt, per;
QUIT;
You can even add your own group headings by applying conditional CASE logic as you did in your question:
PROC SQL;
CREATE TABLE final AS
SELECT
CASE
WHEN trt=1 AND per=1 THEN 'A'
WHEN trt=2 AND per=2 THEN 'B'
WHEN trt=2 AND per=1 THEN 'C'
WHEN trt=1 AND per=2 THEN 'D'
END AS group
avg(m1) AS avg_m1,
avg(m2) AS avg_m2,
count(*) AS n
FROM
test
GROUP BY group;
QUIT;
COUNT(*) simply counts the number of rows found within the group. The AVG function calculates the average for the given column.
In each example, you can replace the explicitly named columns in the GROUP BY clause with a number representing column position in the SELECT clause.
GROUP BY 1,2
However, take care with this method, as adding columns to the SELECT clause later can cause problems.

Check if a column exists and then sum in SAS

This is my input dataset:
Ref Col_A0 Col_01 Col_02 Col_aa Col_03 Col_04 Col_bb
NYC 10 0 44 55 66 34 44
CHG 90 55 4 33 22 34 23
TAR 10 8 0 25 65 88 22
I need to calculate the % of Col_A0 for a specific reference.
For example % col_A0 would be calculated as
10/(10+0+44+55+66+34+44)=.0395 i.e. 3.95%
So my output should be
Ref %Col_A0 %Rest
NYC 3.95% 96.05%
CHG 34.48% 65.52%
TAR 4.58% 95.42%
I can do this part but the issue is column variables.
Col_A0 and Ref are fixed columns so they will be there in the input every time. But the other columns won't be there. And there can be some additional columns too like Col_10, col_11 till col_30 and col_cc till col_zz.
For example the input data set in some scenarios can be just:
Ref Col_A0 Col_01 Col_02 Col_aa Col_03
NYC 10 0 44 55 66
CHG 90 55 4 33 22
TAR 10 8 0 25 65
So is there a way I can write a SAS code which checks to see if the column exists or not. Or if there is any other better way to do it.
This is my current SAS code written in Enterprise Guide.
PROC SQL;
CREATE TABLE output123 AS
select
ref,
(col_A0/(Sum(Col_A0,Col_01,Col_02,Col_aa,Col_03,Col_04,Col_bb)) FORMAT=PERCENT8.2 AS PERCNT_ColA0,
(1-(col_A0/(Sum(Col_A0,Col_01,Col_02,Col_aa,Col_03,Col_04,Col_bb))) FORMAT=PERCENT8.2 AS PERCNT_Rest
From Input123;
quit;
Scenarios where all the columns are not there I get an error. And if there are additional columns then I miss those. Please advice.
Thanks
I would not use SQL, but would use regular datastep.
data want;
set have;
a0_prop = col_a0/sum(of _numeric_);
run;
If you wanted to do this in SQL, the easiest way is to keep (or transform) the dataset in vertical format, ie, each variable a separate row per ID. Then you don't need to know how many variables there are to figure it out.
If you always want to sum all the numeric columns then just do :
col_A0 / sum(of _numeric_)

Confidence intervals on a matrix of data in SAS

I have the following matrix of data, which I am reading into SAS:
1 5 12 19 13
6 3 1 3 14
2 7 12 19 21
22 24 21 29 18
17 15 22 9 18
It represents 5 different species of animal (the rows) in 5 different areas of an environment (the columns). I want to get a Shannon diversity index for the whole environment, so I sum the rows to get:
48 54 68 79 84
Then calculate the Shannon index from this, to get:
1.5873488
What I need to do, however, is calculate a confidence interval for this Shannon index. So I want to perform a nonparametric bootstrap on the initial matrix.
Can anyone advise how this is possible in SAS?
There are several ways to do this in SAS. I would use proc surveyselect to generate the bootstrap samples, and then calculate the Shannon Index for each replicate. (I didn't know what the Shannon Index was, so my code is just based on what I read on Wikipedia.)
data animals;
input v1-v5;
cards;
1 5 12 19 13
6 3 1 3 14
2 7 12 19 21
22 24 21 29 18
17 15 22 9 18
run;
/* Generate 5000 bootstrap samples, with replacement */
proc surveyselect data=animals method=urs n=5 reps=5000 seed=10024 out=boots;
run;
/* For each replicate, calculate the sum of each variable */
proc means data=boots noprint nway;
class replicate;
var v:;
output out=sums sum=;
run;
/* Calculate the proportions, and p*log(p), which will be used next */
data sums;
set sums;
ttl=sum(of v1-v5);
array ps{*} p1-p5;
array vs{*} v1-v5;
array hs{*} h1-h5;
do i=1 to dim(vs);
ps{i}=vs{i}/ttl;
hs{i}=ps{i}*log(ps{i});
end;
keep replicate h:;
run;
/* Calculate the Shannon Index, again for each replicate */
data shannon;
set sums;
shannon = -sum(of h:);
keep replicate shannon;
run;
We now have a data set, shannon, which contains the Shannon Index calculated for each of 5000 bootstrap samples. You could use this to calculate p-values, but if you just want critical values, you can run proc means (or univariate if you want a 5% value, as I don't think it's possible to get 97.5 quantiles with proc means).
proc means data=shannon mean p1 p5 p95 p99;
var shannon;
run;