topic Re: Insert value into a dataset from another dataset in SAS Programming

Insert value into a dataset from another dataset

jpprovost — Mon, 28 Oct 2019 01:29:50 GMT

Hi fellow experts,

I have a dataset containing all the historic (hist_data) informations about a specific kind of data (e.g. mean, min, max, etc.). It all stands in one row and it's updated each month once the latest file is uploaded.

However, for quality control of my latest data (ex: new_data), I would like to use this row of observations (mean, min, max, etc.) to validate datas in another set.

I was thinking of creating a new column into new_data with the row of hist_data and to use it as a comparaison variable for each rows that contains new_data.

I was thinking of creating the new columns in the new_data dataset, but I don't know how to retrieve the data from hist_data into new_data.

Example:

hist_data contains:

mean = 117.8

min = 112.3

max = 122.5

I would like to add new columns into new_data as is :

hist_mean = 117.8

hist_mean = 112.3

hist_mean = 122.5

And to repeat those observations for each row that contains new_data.

Is there a way to do that?

Re: Insert value into a dataset from another dataset

Astounding — Mon, 28 Oct 2019 01:35:02 GMT

Here's one way:

data want;
if _n_=1 then set hist_data (rename=(mean=hist_mean min=hist_min max=hist_max));
set new_data;
run;

Re: Insert value into a dataset from another dataset

jpprovost — Mon, 28 Oct 2019 01:44:06 GMT

But the condition if _n_ = 1 would do it only the line 1?
I want all those datas to be copied for all rows of new_data...

Re: Insert value into a dataset from another dataset

Reeza — Mon, 28 Oct 2019 02:03:10 GMT

@jpprovost wrote:
But the condition if _n_ = 1 would do it only the line 1?
I want all those datas to be copied for all rows of new_data...

Try it and see.

Re: Insert value into a dataset from another dataset

Astounding — Mon, 28 Oct 2019 02:07:18 GMT

Yes, the first SET statement executes only once, and reads in the historical values only once.

However, variables read from a SAS data set are automatically retained. So the values just sit there as the second SET statement reads in each observation from the new data set.

As you were advised, try it and see.

Re: Insert value into a dataset from another dataset

jpprovost — Mon, 28 Oct 2019 16:58:12 GMT

@Astounding wrote:

Yes, the first SET statement executes only once, and reads in the historical values only once.

However, variables read from a SAS data set are automatically retained. So the values just sit there as the second SET statement reads in each observation from the new data set.

As you were advised, try it and see.

I will.

EDIT: Tried and it works. Thanks @Astounding !