topic array function in SAS Programming

array function

joon1 — Tue, 29 Mar 2022 20:10:07 GMT

Dear Madam/Sir,

For each IO industry, I want to multiply numbers in each row for each IO industry with "comp" variable except its own industry (data attached).

For instance, for IO 111CA (farms), comp 0.638957866 x 0.0688737( IO 113FF) + comp 0.761841026 x 0.091003( IO 211) + comp 0.914848186 x 0.0096249 (IO 212) + comp 0.825890645 x 0.000328 (IO 213) + comp 1.0078 x 0.026865 (IO 22) (except IO 111CA, farm). And then repeat the same process for every other industry.

I do not find useful commands. Any help will be highly appreciated to perform this calculation.

Thank you so much.

Joon1

data format

IO	Industry_Description	cyear	Farms	Forestry__fishing__and_related_a	Oil_and_gas_extraction	Mining__except_oil_and_gas	Support_activities_for_mining	Utilities	comp
111CA	Farms	1997	1.18142	0.0590518	0.0007557	0.0026902	0.0012788	0.0006635	0.727964454
113FF	Forestry, fishing, and related activities	1997	0.0688737	1.23167	0.0003183	0.0024397	0.0006637	0.0003304	0.638957866
211	Oil and gas extraction	1997	0.0091003	0.006632	1.08566	0.0158068	0.0070102	0.0970558	0.761841026
212	Mining, except oil and gas	1997	0.0096249	0.002073	0.0028516	1.07108	0.0024438	0.03242	0.914848186
213	Support activities for mining	1997	0.000328	0.0001729	0.0237757	0.0141272	1.0078	0.002556	0.825890645
22	Utilities	1997	0.026865	0.0099835	0.0194369	0.0413922	0.0051409	1.04719	0.961662704

Re: array function

Tom — Tue, 29 Mar 2022 20:17:42 GMT

Can you just assume that the observations (rows) and variables (columns) are in the same order?

data want;
  set have ;
  row+1; 
  array vars farms -- Utilities;
  do col=1 to dim(vars);
      if col ne row then vars[col]=comp*vars[col];
  end;
run;

Re: array function

joon1 — Wed, 30 Mar 2022 01:08:10 GMT

Thank you so much, Tom.

Due to variable name problem related to import, I changed variable name to ind1-ind66 (row and column have the same industry name as attached). And I want to create weight variable to get column "comp" x column industry value except its own industry and revised your code like below. However, I did not get weight variable and only get "row" and "column" variable.

data want; set have;
row+1;
array vars $ ind1-ind66;
array weight $ ind1-ind66;
do col=1 to dim(vars);
if col ne row then
weight[col]=comp*vars[col];
end;
run;

Any help will be highly appreciated.

Joon1

Re: array function

Tom — Wed, 30 Mar 2022 03:18:19 GMT

Why are you defining CHARACTER arrays? If you are going to MULTIPLY the values then the variables must be numeric. Remove the $ from the array statements.

Why are you defining two different arrays that point to the same list of variables? If you only want one set of variables then just define one array to point to them. If you want to make new variables then use new names for the variables in that the other array is pointing to.

Re: array function

joon1 — Wed, 30 Mar 2022 15:00:30 GMT

Thanks for your kind help, Tom. I got changed values by multiplication using your code below.

data want; set have;
row+1;
array vars ind1-ind66;
do col=1 to dim(vars);
if col ne row then
vars[col]=comp*vars[col];
end;
run;

But how can I obtain sum of changed values? I tried to make another array using sum, but it did not work out.

For instance, for IO 111CA (farms), sum= comp 0.638957866 x 0.0688737( IO 113FF) + comp 0.761841026 x 0.091003( IO 211) + comp 0.914848186 x 0.0096249 (IO 212) + comp 0.825890645 x 0.000328 (IO 213) + comp 1.0078 x 0.026865 (IO 22) (except IO 111CA, farm). And then repeat the same process for every other industry.

Your help will be truly appreciated.

Joon1

Re: array function

Tom — Wed, 30 Mar 2022 16:44:37 GMT

Initialize some new variable. Then for each variable in the array add the value that variable should contribute to the new variable. When you have done this for all of the variables in the array then the new variable should have the total. If you want treat missing values as zero then use the SUM(,) function.

See if you can incorporate this idea into your code.

new_var=0;
do col=1 to dim(vars);
   new_var=sum(new_var,comp*vars[col]);
end;

Re: array function

joon1 — Wed, 30 Mar 2022 21:58:27 GMT

Thank you for your kind advice, Tom. I tried following code that is operating, but I did not get the correct summation numbers by year.

It seems that it is difficult to get column sum by year except its own industry in a separate variable. Is there any other way to do this?

data want; set have;
row+1;
array vars ind1-ind65;
do col=1 to dim(vars);
if col ne row then
vars[col]=comp*vars[col];
new_var=0;
new_vars=sum (new_vars,comp*vars[col]); by cyear;
end;
run;

Another way I can think of is transpose data and get row sums. But I face an issue.

(1) I coded ind1-ind65, but after SAS operations, industry character variables are sorted in the order of ind1 ind10-ind19 ind2 ind20-29---- ind7 ind8 ind9.

After transposing the data, I need to get row sums after excluding its own industry, so I need to sort industry variables in the order of ind1 ind2 ---- ind10 ind11----ind65 before transposing the data. Could you please help me to this?

I greatly appreciate your help, Tom.

Joon1

Re: array function

Tom — Thu, 31 Mar 2022 00:16:59 GMT

Isn't the data symmetrical? So the sum across row 5 should be the same number as the sum down column 5.

To get the sum of a variable use PROC MEANS.

Re: array function

Tom — Thu, 31 Mar 2022 00:19:31 GMT

The order that you have the statements in a data step makes a difference.

Do you see the difference between:

x=0;
do ....;
  x=....
end;

And

do ....;
  x=0;
  x=...;
end;

Re: array function

joon1 — Thu, 31 Mar 2022 02:50:49 GMT

Dear Tom,

The data is not symmetrical. I check your two approaches in the order of data step and the output is the same (not what I want to get).

(1) Is it possible to get column sums in SAS?

(2) in the transposing option, how I can make the order of industry variable to ind1, ind2, ind3 through ind65?

Thank you so much,

Joon1

Re: array function

joon1 — Sat, 02 Apr 2022 17:31:50 GMT

I greatly appreciate for your help and time, Tom. I used your basic array statements you suggested and resolved my issues with alteration of raw data in another way.

Joon1