topic Re: Copy first observation till the end in SAS Programming

Dynamically Calculate of Variables

mlogan — Mon, 09 May 2022 21:43:48 GMT

Hello,

I have tuition fees laid out for 4 years (Variables Fee_YR_01-Fee_YR_04) starting current year (Fee_YR_01). Variables Increase_YR_01-Increase_YR_04 in the sample dataset shows the proposed tuition fee increase rate (in percent) based on the previous year. I want to calculate the future tuition based on this proposed tuition increase rate (in the new variables Fee_New_YR_02 - Fee_New_YR_04). I want a dynamic solution for this calculation. Thank you all.

My data set looks like this:

data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
4000	4150	4200	4250	0	15	15	15
4000	4200	4300	4350	0	15	15	15

;
RUN;

This is the output I want:

Fee_New_YR_02	Fee_New_YR_03	Fee_New_YR_04
1200	1260	1320
1200	1284	1320
3450	3565	3622.5
3450	3680	3680
4600	4772.5	4830
4600	4830	4945

Calculations: Fee_New_YR_02=Fee_YR_01 * 1.2 (increased by 20%)

I have shown you a small set of data. But I have 150 variables for tuition fees and 150 variables for the tuition rate increase. So I need help on how to do it dynamically.

Dynamic Calculations of Variables

mlogan — Mon, 09 May 2022 21:40:03 GMT

Hello,

My data set looks like this:

data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
4000	4150	4200	4250	0	15	15	15
4000	4200	4300	4350	0	15	15	15

;
RUN;

This is the output I want:

Fee_New_YR_02	Fee_New_YR_03	Fee_New_YR_04
1200	1260	1320
1200	1284	1320
3450	3565	3622.5
3450	3680	3680
4600	4772.5	4830
4600	4830	4945

Calculations: Fee_New_YR_02=Fee_YR_01 * 1.2 (increased by 20%)

I have shown you a small set of data. But I have 150 variables for tuition fees and 150 variables for the tuition rate increase. So I need help on how to do it dynamically.

Re: Dynamically Calculate of Variables

Reeza — Mon, 09 May 2022 22:24:51 GMT

Please do not post the question in multiple locations.

Update your dimensions and variable series accordingly and this should work:


data want;
set have;

array fee_hist (4) fee_yr_01 - fee_yr_04;
array increase(4) increase_yr_01 - increase_yr_04;
array fee_new (2:4) fee_new_yr_02 - fee_new_yr_04;

do i=2 to 4;
fee_new(i) = fee_hist(i-1) * (1+(increase(i)/100));
end;

run;

Or slightly more dynamically, update your end of the series:

data want;
set have;

array fee_hist (*) fee_yr_01 - fee_yr_04;
array increase(*) increase_yr_01 - increase_yr_04;
array fee_new (*) fee_new_yr_02 - fee_new_yr_04;

do i=2 to dim(fee_hist);
fee_new(i-1) = fee_hist(i-1) * (1+(increase(i)/100));
end;

run;

Here's a tutorial on using Arrays in SAS
https://stats.idre.ucla.edu/sas/seminars/sas-arrays/

@mlogan wrote:

Hello,

I have tuition fees laid out for 4 years (Variables Fee_YR_01-Fee_YR_04) starting current year (Fee_YR_01). Variables Increase_YR_01-Increase_YR_04 in the sample dataset shows the proposed tuition fee increase rate (in percent) based on the previous year. I want to calculate the future tuition based on this proposed tuition increase rate (in the new variables Fee_New_YR_02 - Fee_New_YR_04). I want a dynamic solution for this calculation. Thank you all.

My data set looks like this:
data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
4000	4150	4200	4250	0	15	15	15
4000	4200	4300	4350	0	15	15	15

;
RUN;
This is the output I want:

Fee_New_YR_02 Fee_New_YR_03 Fee_New_YR_04

1200 1260 1320

1200 1284 1320

3450 3565 3622.5

3450 3680 3680

4600 4772.5 4830

4600 4830 4945

Calculations: Fee_New_YR_02=Fee_YR_01 * 1.2 (increased by 20%)

I have shown you a small set of data. But I have 150 variables for tuition fees and 150 variables for the tuition rate increase. So I need help on how to do it dynamically.

Re: Dynamically Calculate of Variables

mlogan — Sun, 15 May 2022 13:32:17 GMT

Thank you Reeza. Your code worked for me. I just have slightly different requirements now and wondering if you can help.

I want the calculated output of the first row will be copied below all the way to the end.

I was able to do the calculation on the first line, but don't know how to copy downward. Thank you for your help.

data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
;
RUN;

DATA Want;
SET  Have;

ARRAY Increase_Rate(*) Increase_YR_01 - Increase_YR_04;
ARRAY Fee_New(*)        Fee_New_AY_01 - Fee_New_AY_04;

Fee_New_AY_01=Fee_YR_01;
   DO i=2 TO dim(Fee_New);
   
	IF _n_=1 THEN fee_new(i) = FLOOR(( fee_new(i-1) * (1+(Increase_Rate(i)/100)) )/10)*10;
    
END;
DROP i;
RUN;

Expected Output:

Fee_YR_01	Fee_YR_02	Fee_YR_03	Fee_YR_04	Increase_YR_01	Increase_YR_02	Increase_YR_03	Increase_YR_04	Fee_New_AY_01	Fee_New_AY_02	Fee_New_AY_03	Fee_New_AY_04
1000	1050	1100	1150	0	20	20	20	1000	1200	1440	1720
1000	1070	1100	1150	0	20	20	20	1000	1200	1440	1720
3000	3100	3150	3200	0	15	15	15	3000	1200	1440	1720
3000	3200	3200	3300	0	15	15	15	3000	1200	1440	1720

Copy first observation till the end

mlogan — Mon, 16 May 2022 03:09:59 GMT

Hi all,

I have lat 4 year tuition fee laid out as Fee_YR_01-Fee_YR_04 and their corresponding increased rate Increase_YR_01-Increase_YR_04. I want 4 new rows which will calculate the tuition fee for the next 4 years based on their previous year tuitions and corresponding increase. But instead of calculating all 4 rows, I want the calculated output of the first row to be copied below all the way to the end.

I was able to do the calculation on the first row, but don't know how to copy downward. Can anyone help please. Thank you

data have;
	input Fee_YR_01 Fee_YR_02 Fee_YR_03 Fee_YR_04 Increase_YR_01 Increase_YR_02 Increase_YR_03 Increase_YR_04;
datalines;
1000	1050	1100	1150	0	20	20	20
1000	1070	1100	1150	0	20	20	20
3000	3100	3150	3200	0	15	15	15
3000	3200	3200	3300	0	15	15	15
;
RUN;

DATA Want;
SET  Have;

ARRAY Increase_Rate(*) Increase_YR_01 - Increase_YR_04;
ARRAY Fee_New(*)        Fee_New_AY_01 - Fee_New_AY_04;

Fee_New_AY_01=Fee_YR_01;
   DO i=2 TO dim(Fee_New);
   
	IF _n_=1 THEN fee_new(i) = FLOOR(( fee_new(i-1) * (1+(Increase_Rate(i)/100)) )/10)*10;
    
END;
DROP i;
RUN;

Expected Output:

Fee_YR_01	Fee_YR_02	Fee_YR_03	Fee_YR_04	Increase_YR_01	Increase_YR_02	Increase_YR_03	Increase_YR_04	Fee_New_AY_01	Fee_New_AY_02	Fee_New_AY_03	Fee_New_AY_04
1000	1050	1100	1150	0	20	20	20	1000	1200	1440	1720
1000	1070	1100	1150	0	20	20	20	1000	1200	1440	1720
3000	3100	3150	3200	0	15	15	15	3000	1200	1440	1720
3000	3200	3200	3300	0	15	15	15	3000	1200	1440	1720

Re: Copy first observation till the end

mkeintz — Mon, 16 May 2022 03:22:26 GMT

Look up the RETAIN statement, which tells SAS to avoid resetting new variables to missing values from iteration to iteration. You apparently want to retain the values of the Fee_New_AY_01 - Fee_New_AY_04 variables calculated when _n_=1.

Re: Copy first observation till the end

andreas_lds — Mon, 16 May 2022 06:23:42 GMT

I have merged your posts, please don't repost questions.

Re: Copy first observation till the end

mlogan — Mon, 16 May 2022 17:13:36 GMT

Thank you mkeintz. It worked for me perfectly. Never used this RETAIN function before. Today I have learded something new.

Re: Copy first observation till the end

mlogan — Mon, 16 May 2022 19:17:09 GMT

Hi mkeintz, Do you know how I can stop RETAIN function to copy the value all the way till the blank line? I want it to stop at one point when my another by value (sorted column) ends.

Thanks.