topic Re: #Doubt regarding the flow of the code in SAS Programming

#Doubt regarding the flow of the code

Hemanth003 — Sun, 14 Jan 2018 23:56:43 GMT



proc sort data=cars out=sortcars;
   by type;
run;

data tourdetails
     vendordetails;
   set sortcar;
   by type;
   Money=Wheelbase *Length;
   output tourdetails;
   if First.type then
      do;
         VendorMoney=0;
      end;
   VendorMoney + Money;
   if Last.type then output vendordetails;
run;

proc print data=tourdetails;
   title 'Detail Records: Dollars Spent on Individual Tours';
run;

proc print data=vendordetails;
   title 'Vendor Totals: Dollars Spent and Bookings by Vendor';
run;

iam new to SAS, can someone please explain me the flow of the code??

i have attached the input data below.

what will be the output?

Re: #Doubt regarding the flow of the code

novinosrin — Sun, 14 Jan 2018 22:05:52 GMT

Hi, what doubt do you have?

Re: #Doubt regarding the flow of the code

Hemanth003 — Sun, 14 Jan 2018 22:14:36 GMT

please check the output file below, why there is a zero in the tourdetails tables first field whereas vendor details doesn't have it

Re: #Doubt regarding the flow of the code

novinosrin — Sun, 14 Jan 2018 22:16:13 GMT

I'm afraid I can't open attachments. Can you please paste as text

Re: #Doubt regarding the flow of the code

Hemanth003 — Sun, 14 Jan 2018 22:19:13 GMT

type wheelbase Length Money VendorMoney

Hybrid	103	175	18025	0
Hybrid	95	55	5225	18025
Hybrid	106	175	18550	23250
SUV	106	189	20034	41800
SUV	110	180	19800	20034
SUV	111	184	20424	39834

Vendor Totals: Dollars Spent and Bookings by Vendor

type wheelbase Length Money VendorMoney

Hybrid	103	175	18025	18025
Hybrid	95	55	5225	23250
Hybrid	106	175	18550	41800
SUV	106	189	20034	20034
SUV	110	180	19800	39834
SUV	111	184	20424	60258

I meant about the vendormoney column in both the tables!!!

Re: #Doubt regarding the flow of the code

novinosrin — Sun, 14 Jan 2018 22:39:22 GMT

OK,

Here you go-:

1. At compile time, SAS reads the descriptive portion of the input dataset(cars) and builds the PDV. So you have all your variable names from your input dataset and your variables that is created in the program as assignment statements and initializes with a value of missing. However in this case, since Vendormoney's assignment is on sum statement, the initial assignment is a zero instead of missing.

2. At execution time or while execution happens, take your first obs from cars SAS read the values and starts processing. However your explicit output (output tourdetails; ) writes the obs to the output datasettourdetails even before calculating Vendormoney with its existing value that is zero.

3. However the output vendordetails statement does not execute before the sum statement, therefore you do not have zero.

In essence statements are executed sequentially, unless you use goto, return, link et al statements. Hope that helps

Re: #Doubt regarding the flow of the code

art297 — Sun, 14 Jan 2018 22:54:05 GMT

I agree with @novinosrin's explanation but, given your code, VendorMoney won't even be in tourdetails since you drop that variable in your code. Also, you create sortcars in your proc sort step, but then set sortcar in your datastep. Obviously, the output you posted was not from the code you posted.

Art, CEO, AnalystFinder.com

Re: #Doubt regarding the flow of the code

Hemanth003 — Sun, 14 Jan 2018 22:56:26 GMT

I am sorry I should have removed those commands and should have posted.

Re: #Doubt regarding the flow of the code

Hemanth003 — Sun, 14 Jan 2018 23:50:18 GMT

Thank you!! That was very helpful:)

Re: #Doubt regarding the flow of the code

art297 — Sun, 14 Jan 2018 23:54:30 GMT

You really should change the correct solution to the response provided by @novinosrin. I was simply pointing out the inconsistency in your code.

Art, CEO, AnalystFinder.com