I was trying to use boxplot to exam the relationship between categorical and multiple numerical variables. I am using the breast cancer dataset from kaggle:
https://www.kaggle.com/uciml/breast-cancer-wisconsin-data
The data have column 'diagnosis' to be the classification criteria/dependent variable (which is categorical) and 30 other columns (all numeric) as explanatory variable such as 'radius_mean' 'radius_se' 'radius_worst' etc.
My question is instead of list all 30 variables by their names
'plot (radius_mean radius_se ... )*diagnosis;',
Is there a way to refer to all 30 variable names using a simpler command?
Thanks!
Just use the system view VCOLUMN to ask sas itself what fields it has
proc sql
select name
into :num_vars separated by ' '
from SASHELP.VCOLUMN
where libname = 'YOUR_LIB' /* upper case */
and memname = 'YOUR_MEMBER' /* upper case */
and name not in ('id', 'diagnosis'); /* correct case */
quit;
This creates a macro variable that lists all the variables you need
%put &num_vars;
Now use that
proc boxplot data=YOUR_LIB.YOUR_MEMBER;
plot (&num_vars)*diagnosis;
run;
Related
I have a dataset with 20 columns all starting with the name morb_, which are all 1 or 2, coded as No and Yes. There is an additional column called Pat_TNO which is the patient reference number. Patients have more than one row.
I wish to create a new dataset which summarises whether each patient has had at least one of each type of event. So far the code I have written works perfectly, but is there a way to simplify it using an array?
proc sql;
select
Pat_TNO,
max(morb_1) as morb_1 format yn.,
max(morb_2) as morb_2 format yn. /* etc etc */
from morbidity
group by Pat_TNO;
quit;
COumn names aren't morb_1 and morb_2, rather morb_amputation, morb_mi, morb_tia, etc.
proc summary data=morbidity nway missing;
class pat_tno;
output out=max max(morb_:) = ;
run;
I'm working on code that will change the coding of several hundred variables stored as 1/0 or Y/N in numeric 1 or 0. Because this will need to be in a flexible process, I am writing a macro to do so. The only issue that I am have with the macro is I am unable to pass the SAS column names to the macro to work. Thoughts?
%Macro Test(S,E);
%Array(A,&S.-&E.);
%MEnd;
data subset;
set dataset);
%Test(v1,v20)
run;
SAS supports variable lists. Macro parameters are just text strings. So as long as you use the macro variable value in a place where SAS supports variable lists there is no problem passing a variable list to a macro. For example here a simplistic macro to make an array statement.
%macro array(name,varlist);
array &name &varlist ;
%mend;
Which you could then use in the middle of a data step like this.
data want;
set have ;
%array(binary,var1-var20 a--d male education);
do over binary; binary=binary in ('Y','1','T'); end;
run;
The difficult part is if you want to convert variables from character to numeric then you will need to rename them. This will make it difficult to use variable lists (x1-x5 or vara -- vard). You can solve that problem with a little extra logic to convert the variable lists into a list of individual names. For example you can use PROC TRANSPOSE to create a dataset with the variable names that match your list.
proc transpose data=&inds(obs=0) out=_names ;
var &varlist;
run;
You could then use this dataset to generate code or generate a list of the individual variable names.
proc sql noprint ;
select name into :varlist2 separated by ' ' from _names;
quit;
A list of all variable names is stored in the dictionary.columns dataset. You can access it and store the names as a list that you can then loop through:
proc sql noprint;
select name into: list_of_names
separated by " "
from dictionary.columns where memname = upcase("your_dataset");
quit;
%put &list_of_names.;
Completely new to SAS here.
I have a data set with a huge amount of variables. I would like to extract all the variables that for example contains the string "GRP" within its name, and create a new data set from these variables.
EDIT: I do not know any of the variable names, as the data set is huge.
You can first store the variables you're interested into a macro variable and then use them in a keep list. Using data set name work.have as an example to create work.want:
/* note the use of use UPPERCASE */
proc sql noprint;
select name into :varlist separated by ' '
from dictionary.columns
where libname='WORK'
and memname='HAVE'
and upper(name) contains 'GRP'
;
quit;
/* keep only required variables */
data want;
set have(keep=&varlist);
run;
I have a table with postings by category (a number) that I transposed. I got a table with each column name as _number for example _16, _881, _853 etc. (they aren't in order).
I need to do the sum of all of them in a proc sql, but I don't want to create the variable in a data step, and I don't want to write all of the columns names either . I tried this but doesn't work:
proc sql;
select sum(_815-_16) as nnl
from craw.xxxx;
quit;
I tried going to the first number to the last and also from the number corresponding to the first place to the one corresponding to the last place. Gives me a number that it's not correct.
Any ideas?
Thanks!
You can't use variable lists in SQL, so _: and var1-var6 and var1--var8 don't work.
The easiest way to do this is a data step view.
proc sort data=sashelp.class out=class;
by sex;
run;
*Make transposed dataset with similar looking names;
proc transpose data=class out=transposed;
by sex;
id height;
var height;
run;
*Make view;
data transpose_forsql/view=transpose_forsql;
set transposed;
sumvar = sum(of _:); *I confirmed this does not include _N_ for some reason - not sure why!;
run;
proc sql;
select sum(sumvar) from transpose_Forsql;
quit;
I have no documentation to support this but from my experience, I believe SAS will assume that any sum() statement in SQL is the sql-aggregate statement, unless it has reason to believe otherwise.
The only way I can see for SAS to differentiate between the two is by the way arguments are passed into it. In the below example you can see that the internal sum() function has 3 arguments being passed in so SAS will treat this as the SAS sum() function (as the sql-aggregate statement only allows for a single argument). The result of the SAS function is then passed in as the single parameter to the sql-aggregate sum function:
proc sql noprint;
create table test as
select sex,
sum(sum(height,weight,0)) as sum_height_and_weight
from sashelp.class
group by 1
;
quit;
Result:
proc print data=test;
run;
sum_height_
Obs Sex and_weight
1 F 1356.3
2 M 1728.6
Also note a trick I've used in the code by passing in 0 to the SAS function - this is an easy way to add an additional parameter without changing the intended result. Depending on your data, you may want to swap out the 0 for a null value (ie. .).
EDIT: To address the issue of unknown column names, you can create a macro variable that contains the list of column names you want to sum together:
proc sql noprint;
select name into :varlist separated by ','
from sashelp.vcolumn
where libname='SASHELP'
and memname='CLASS'
and upcase(name) like '%T' /* MATCHES HEIGHT AND WEIGHT */
;
quit;
%put &varlist;
Result:
Height,Weight
Note that you would need to change the above wildcard to match your scenario - ie. matching fields that begin with an underscore, instead of fields that end with the letter T. So your final SQL statement will look something like this:
proc sql noprint;
create table test as
select sex,
sum(sum(&varlist,0)) as sum_of_fields_ending_with_t
from sashelp.class
group by 1
;
quit;
This provides an alternate approach to Joe's answer - though I believe using the view as he suggests is a cleaner way to go.
I have a SAS dataset which has 20 character variables, all of which are names (e.g. Adam, Bob, Cathy etc..)
I would like a dynamic code to create variables called Adam_ref, Bob_ref etc.. which will work even if there a different dataset with different names (i.e. don't want to manually define each variable).
So far my approach has been to use proc contents to get all variable names and then use a macro to create macro variables Adam_ref, Bob_ref etc..
How do I create actual variables within the dataset from here? Do I need a different approach?
proc contents data=work.names
out=contents noprint;
run;
proc sort data = contents; by varnum; run;
data contents1;
set contents;
Name_Ref = compress(Name||"_Ref");
call symput (NAME, NAME_Ref);
%put _user_;
run;
If you want to create an empty dataset that has variables named like some values you have in a macro variables you could do something like this.
Save the values into macro variables that are named by some pattern, like v1, v2 ...
proc sql;
select compress(Name||"_Ref") into :v1-:v20 from contents;
quit;
If you don't know how many values there are, you have to count them first, I assumed there are only 20 of them.
Then, if all your variables are character variables of length 100, you create a dataset like this:
%macro create_dataset;
data want;
length %do i=1 %to 20; &&v&i $100 %end;
;
stop;
run;
%mend;
%create_dataset; run;
This is how you can do it if you have the values in macro variable, there is probably a better way to do it in general.
If you don't want to create an empty dataset but only change the variable names, you can do it like this:
proc sql;
select name into :v1-:v20 from contents;
quit;
%macro rename_dataset;
data new_names;
set have(rename=(%do i=1 %to 20; &&v&i = &&v&i.._ref %end;));
run;
%mend;
%rename_dataset; run;
You can use PROC TRANSPOSE with an ID statement.
This step creates an example dataset:
data names;
harry="sally";
dick="gordon";
joe="schmoe";
run;
This step is essentially a copy of your step above that produces a dataset of column names. I will reuse the dataset namerefs throughout.
proc contents data=names out=namerefs noprint;
run;
This step adds the "_Refs" to the names defined before and drops everything else. The variable "name" comes from the column attributes of the dataset output by PROC CONTENTS.
data namerefs;
set namerefs (keep=name);
name=compress(name||"_Ref");
run;
This step produces an empty dataset with the desired columns. The variable "name" is again obtained by looking at column attributes. You might get a harmless warning in the GUI if you try to view the dataset, but you can otherwise use it as you wish and you can confirm that it has the desired output.
proc transpose out=namerefs(drop=_name_) data=namerefs;
id name;
run;
Here is another approach which requires less coding. It does not require running proc contents, does not require knowing the number of variables, nor creating a macro function. It also can be extended to do some additional things.
Step 1 is to use built-in dictionary views to get the desired variable names. The appropriate view for this is dictionary.columns, which has alias of sashelp.vcolumn. The dictionary libref can be used only in proc sql, while th sashelp alias can be used anywhere. I tend to use sashelp alias since I work in windows with DMS and can always interactively view the sashelp library.
proc sql;
select compress(Name||"_Ref") into :name_list
separated by ' '
from sashelp.vcolumn
where libname = 'WORK'
and memname = 'NAMES';
quit;
This produces a space delimited macro vaiable with the desired names.
Step 2 To build the empty data set then this code will work:
Data New ;
length &name_list ;
run ;
You can avoid assuming lengths or create populated dataset with new variable names by using a slightly more complicated select statement.
For example
select compress(Name)||"_Ref $")||compress(put(length,best.))
into :name_list
separated by ' '
will generate a macro variable which retains the previous length for each variable. This will work with no changes to step 2 above.
To create populated data set for use with rename dataset option, replace the select statement as follows:
select compress(Name)||"= "||compress(_Ref")
into :name_list
separated by ' '
Then replace the Step 2 code with the following:
Data New ;
set names (rename = ( &name_list)) ;
run ;