I'm new to SAS and have some problems with adding a column to existing data set in SAS using MODIFY statement (without proc sql).
Let's say I have data like this
id name salary perks
1 John 2000 50
2 Mary 3000 120
What I need to get is a new column with the sum of salary and perks.
I tried to do it this way
data data1;
modify data1;
money=salary+perks;
run;
but apparently it doesn't work.
I would be grateful for any help!
As #Tom mentioned you use SET to access the dataset.
I generally don't recommend programming this way with the same name in set and data statements, especially as you're learning SAS. This is because it's harder to detect errors, since once run and encounter an error, you destroy your original dataset and have to recreate it before you start again.
If you want to work step by step, consider intermediary datasets and then clean up after you're done by using proc datasets to delete any unnecessary intermediary datasets. Use a naming conventions to be able to drop them all at once, i.e. data1, data2, data3 can be referenced as data1-data3 or data:.
data data2;
set data1;
money = salary + perks;
run;
You do now have two datasets but it's easy to drop datasets later on and you can now run your code in sections rather than running all at once.
Here's how you would drop intermediary datasets
proc datasets library=work nodetails holist;
delete data1-data3;
run;quit;
You can't add a column to an existing dataset. You can make a new dataset with the same name.
data data1;
set data1;
money=salary+perks;
run;
SAS will build it as a new physical file (with a temporary name) and when the step finishes without error it deletes the original and renames the new one.
If you want to use a data set you do it like this:
data dataset;
set dataset;
format new_column $12;
new_column = 'xxx';
run;
Or use Proc SQL and ALTER TABLE.
proc sql;
alter table dataset
add new_column char(8) format = $12.
;
quit;
Related
I am a newbie to SAS and I am trying to execute below code to obtain all the information for a particular library. However it fails in between due to data in a particular dataset. Is there any way to read dataset names from a different dataset and loop through them creating a different dataset specific to each datasetname from the list?
Proc contents data= testlib. _ALL_ out=x;
Run;
Instead I want something like this
Proc contents data in (work. Tbnames) out = x;
Run;
And read data from below data set.
Data tbnames(keep tablename) ;
Set WORK. tablenames;
Run;
Please help
St
Proc contents data = work.Tbnames out = x;
Run;
Use Proc COPY to copy data sets from one library to another.
libname testlib '<os-path-to-folder>';
proc copy in=testlib out=work memtype=DATA;
run;
Read the data from dictionary.table instead.
This assumes that you have the list of tables in a data set called tableNames and it has a variable called tName, which is the variable name. Note that it is a case sensitive comparison so UPCASE() is used make it all upper case.
proc sql;
create table summary as
select *
from dictionary.table
where memname in (select upcase(tName) from tableNames);
quit;
Or look at PROC DATASETS which operates on a library, not a single data set.
proc datasets lib=myLib;
run;quit;
I know this is a very basic question but my code keeps failing when trying to run what I found through the help documentation.
Up to now I have been running an analysis project off of the .WORK directory which I understand gets wiped out every time a session ends. I have done a bunch of data cleaning and preparation and do not want to have to do that every time before I start my analysis.
So I understand, from reading this: https://support.sas.com/documentation/cdl/en/basess/58133/HTML/default/viewer.htm#a001310720.htm that I have to output the cleaned dataset to a non-temporary directory.
Steps I have taken so far:
1) created a new Library called "Project"
2) Saved it in a folder that I have under "my folders" in SAS
3) My code for saving the cleaned dataset to the "Project" library is as follows:
PROC SORT DATA=FAA_ALL NODUPKEY;
BY GROUND_SPEED;
DATA PROJECT.FAA_ALL;
RUN;
Then I run this code in a new program:
PROC PRINT DATA=PROJECT.FAA_ALL;
RUN;
It says there are no observations and that the dataset is essentially empty.
Can some tell me where I'm going wrong?
Your problem is the PROC SORT
PROC SORT DATA=FAA_ALL NODUPKEY;
BY GROUND_SPEED;
DATA PROJECT.FAA_ALL;
RUN;
Should be
PROC SORT DATA=FAA_ALL OUT= PROJECT.FAA_ALL NODUPKEY;
BY GROUND_SPEED;
RUN;
That DATA PROJECT.FAA_ALL was starting a Data Step creating a blank data set.
Something else worth mentioning: your data step didn't do what you might have expected because you had no set statement. Your code was equivalent to:
PROC SORT DATA=WORK.FAA_ALL NODUPKEY;
BY GROUND_SPEED;
RUN;
DATA PROJECT.FAA_ALL;
SET _NULL_;
RUN;
PROJECT.FAA_ALL is empty because nothing was read in.
The SORT procedure implicitly sorts a dataset in-place. You could have SAS move the sorted data by adding the set statement to your data step:
PROC SORT DATA=WORK.FAA_ALL NODUPKEY;
BY GROUND_SPEED;
RUN;
DATA PROJECT.FAA_ALL;
SET WORK.FAA_ALL;
RUN;
However, this still takes two steps, and requires extra disk I/O. Using the out option in a SAS procedure (as in DomPazz's answer) is almost always faster and more efficient than using a data step just to move data.
I have the following problem. We have several streams in Enterprise Miner and we would like to be able to tell how long was each run. I have tried to create a macro that would save the start and end time/date but the problem is that global variables defined in a node, are not seen anymore in a subsequent node (so are global only inside a node, but not between nodes). How people usually solve the problem? Any idea or suggestion?
Thanks, Umberto
Just write out timestamps to log (EM should produce a global log in the same fashion that EG and DI do)
Either use:
data _null_;
datetime = datetime();
put datetime= datetime20.;
run;
or macro language:
%put EM node started at at %sysfunc(time(),timeampm.) on %sysfunc(date(),worddate.).;
with a higly customised message you have read the log in SAS looking for those strings using regex.
Solution 2:
Other option is to created a table in a library that is visible from EM and EG for example and have sql inserts at the beginning/end of your process.
proc sql;
create table EM_logger
(jobcode char(100),
timestamp num informat=datetime20. format=datetime20.);
quit;
proc sql;
insert into EM_logger values('Begining Linear Reg',%sysfunc(datetime()));
quit;
data w;
do i=1 to 10000000;
output;
end;
run;
proc sql;
insert into EM_logger values('End Linear Reg',%sysfunc(datetime()));
quit;
Table layout can be as complex as you want and as long as you can access it you can get your statistics.
Hope it helps
I have a data where I have various types of loan descriptions, there are at least 100 of them.
I have to categorise them into various buckets using if and then function. Please have a look at the data for reference
data des;
set desc;
if loan_desc in ('home_loan','auto_loan')then product_summary ='Loan';
if loan_desc in ('Multi') then product_summary='Multi options';
run;
For illustration I have shown it just for two loan description, but i have around 1000 of different loan_descr that I need to categorise into different buckets.
How can I categorise these loan descriptions in different buckets without writing the product summary and the loan_desc again and again in the code which is making it very lengthy and time consuming
Please help!
Another option for categorizing is using a format. This example uses a manual statement, but you can also create a format from a dataset if you have the to/from values in a dataset. As indicated by #Tom this allows you to change only the table and the code stays the same for future changes.
One note regarding your current code, you're using If/Then rather than If/ElseIf. You should use If/ElseIf because then it terminates as soon as one condition is met, rather than running through all options.
proc format;
value $ loan_fmt
'home_loan', 'auto_loan' = 'Loan'
'Multi' = 'Multi options';
run;
data want;
set have;
loan_desc = put(loan, $loan_fmt.);
run;
For a mapping exercise like this, the best technique is to use a mapping table. This is so the mappings can be changed without changing code, among other reasons.
A simple example is shown below:
/* create test data */
data desc (drop=x);
do x=1 to 3;
loan_desc='home_loan'; output;
loan_desc='auto_loan'; output;
loan_desc='Multi'; output;
loan_desc=''; output;
end;
data map;
loan_desc='home_loan'; product_summary ='Loan '; output;
loan_desc='auto_loan'; product_summary ='Loan'; output;
loan_desc='Multi'; product_summary='Multi options'; output;
run;
/* perform join */
proc sql;
create table des as
select a.*
,coalescec(b.product_summary,'UNMAPPED') as product_summary
from desc a
left join map b
on a.loan_desc=b.loan_desc;
There is no need to use the macro language for this task (I have updated the question tag accordingly).
Already good solutions have been proposed (I like #Reeza's proc format solution), but here's another route which also minimizes coding.
Generate sample data
data have;
loan_desc="home_loan"; output;
loan_desc="auto_loan"; output;
loan_desc="Multi"; output;
loan_desc=""; output;
run;
Using PROC SQL's case expression
This way doesn't allow, to my knowledge, having several criteria on a single when line, but it really simplifies coding since the resulting variable's name needs to be written down only once.
proc sql;
create table want as
select
loan_desc,
case loan_desc
when "home_loan" then "Loan"
when "auto_loan" then "Loan"
when "Multi" then "Multi options"
else "Unknown"
end as product_summary
from have;
quit;
Otherwise, using the following syntax is also possible, giving the same results:
proc sql;
create table want as
select
loan_desc,
case
when loan_desc in ("home_loan", "auto_loan") then "Loan"
when loan_desc = "Multi" then "Multi options"
else "Unknown"
end as product_summary
from have;
quit;
I am working with multiple waves of survey data. I have finished defining formats and labels for the first wave of data.
The second wave of data will be different, but the codes, labels, formats, and variable names will all be the same. I do not want to define all these attributes again...it seems like there should be a way to export the PROC CONTENTS information for one dataset and import it into another dataset. Is there a way to do this?
The closest thing I've found is PROC CPORT but I am totally confused by it and cannot get it to run.
(Just to be clear I'll ask the question another way as well...)
When you run PROC CONTENTS, SAS tells you what format, labels, etc. it is using for each variable in the dataset.
I have a second dataset with the exact same variable names. I would like to use the variable attributes from the first dataset on the variables in the second dataset. Is there any way to do this?
Thanks!
So you have a MODEL dataset and a HAVE dataset, both with data in them. You want to create WANT dataset which has data from HAVE, with attributes of MODEL (formats, labels, and variable lengths). You can do this like:
data WANT ;
if 0 then set MODEL ;
set HAVE ;
run ;
This works because when the DATA step compiles, SAS builds the Program Data Vector (PDV) which defines variable attributes. Even though the SET MODEL never executes (because 0 is not true), all of the variables in MODEL are created in the PDV when the step compiles.
Importantly, note that if there are corresponding variables with different lengths, the length from MODEL will determine the length of the variable in WANT. So if HAVE has a variable that is longer than the same-named variable in MODEL, it may be truncated. Options VARLENCHK determines whether or not SAS throws a warning/error if this happens.
That assumes there are no formats/labels on the HAVE dataset. If there is a variable in HAVE that has a format/label, and the corresponding variable in MODEL does not have a format/label, the format/label from HAVE will be applied to WANT.
Sample code below.
data model;
set sashelp.class;
length FavoriteColor $3;
FavoriteColor="Red";
dob=today();
label
dob='BirthDate'
;
format
dob mmddyy10.
;
run;
data have;
set sashelp.class;
length FavoriteColor $10;
dob=today()-1;
FavoriteColor="Orange";
label
Name="HaveLabel"
dob="HaveLabel"
;
format
Name $1.
dob comma.
;
run;
options varlenchk=warn;
data want;
if 0 then set model;
set have;
run;
I'd create an empty dataset based on the existing one, and then use proc append to append the contents to it.
Create some sample data for the second round of data:
data new_data;
age = 10;
run;
Create an empty dataset based on the original data:
proc sql noprint;
create table want like sashelp.class;
quit;
Append the data into the empty dataset, retaining the details from the original:
proc append base=want data=new_data force nowarn;
run;
Note that I've used the force and nowarn options on proc append. This will ensure the data is appended even if differences are found between the two datasets being used. This is expected if you have, for example, format differences. It will also hide things like if columns exist in the new table that aren't in the old table etc. So be careful that this is doing what you want it to. If the behaviour is undesirable, consider using a datastep to append instead (and list the want dataset first).
Welcome to the stack.
If you want to copy the properties of the table without the data within it, you could use PROC SQL or data step with zero rows read in.
This examples copies all information about the SASHELP.CLASS dataset into a brand new dataset. All formats, attributes, labels, the whole thing is copies over. If you want to only copy some of the columns, specify them in select clause instead of asterix.
PROC SQL outobs=0;
CREATE TABLE WANT as SELECT * FROM SASHELP.CLASS;
QUIT;
Regards,
Vasilij