Hi Everyone,
I have data of 2 columns ID and T.
T have value of -500, -3, 0, 3, 500.
For a give row, I want to look back, say 12 rows and “count how many of T having the same Non-Zero value Before T change to a different non-zero value”.
In the data below, for the 1 row I see:
1st series_value is 500 and has 2 counts and the SUM_series1 is 1000
2nd series_value is 3 and has 3 counts and the SUM_series2 is 9
3rd series_value is -3 and has 2 counts and the SUM_series3 is -6
4th series_value is -500 and has 1 count and the SUM_series4 is -500
5th series_value is 500 and has 1 count and the SUM_series5 is 500
In the count, clearly 0 can be removed but I still need it to keep the track of the looking back.
I only need up to 5th series.
So the output data should have following column (number in parenthesis is value of each column for 1st row which associated with above explanation) :
ID T
series1_value(500) SUM_series1 (1000)
series2_value (3) SUM_series2 (9)
series3_value (-3) SUM_series3 (-6)
series4_value (-500) SUM_series4 (-500)
series5_value (500) SUM_series5 (500)
Can you please help me with that?
Thank you so much.
HHC
data have;
input ID T;
datalines;
1 0
1 500
1 500
1 0
1 3
1 0
1 0
1 3
1 3
1 -3
1 0
1 -3
1 -500
1 0
1 0
1 500
1 -5
1 -500
1 0
2 0
2 3
2 3
2 0
;run;
So I do nested loop to count the series of number (TT) with the same value.
The basic idea is:
Start with 1st row. Keep TT value in value_series_1
.
Loop to next row, if TT is the same as value_series_1
increase the N_series_1
by 1. If not the same, it is the start of value_series_2
My code below work with lookback=12. It gives correct result for the first few rows but then at rows 8, number look weird with the N_series inflated to 30+.
Same thing when lookback=4, the error show right on the first row.
Look like the script doesn't stop at i+&lookback
DO j=i+1 to i+&lookback until (End_run=1);
I can't find the problem and really appreciate it if you could help.
Thanks,
HHC
data have;
input ID TT;
datalines;
1 500
1 500
1 3
1 3
1 3
1 -3
1 -3
1 -500
1 500
1 -5
1 -500
1 3
1 3
;run;
%let lookback=5;
data want;
set have;
drop i End_run ID1-ID5 TT1-TT5;
i+1;
End_run=0;
N_series_1 = 0; value_series_1 =0;
N_series_2 = 0; value_series_2 =0;
N_series_3 = 0; value_series_3 =0;
N_series_4 = 0; value_series_4 =0;
N_series_5 = 0; value_series_5 =0;
N_series_1 = 1; value_series_1 =TT;
DO j=i+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID1 TT=TT1)) point=j nobs=nobs1;
if TT1=value_series_1 then N_series_1=N_series_1+1;
else
if TT1^=value_series_1 then do;
N_series_2=N_series_2+1; value_series_2=TT1;
DO k=j+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID2 TT=TT2)) point=k nobs=nobs2;
if TT2=value_series_2 then N_series_2=N_series_2+1;
else
if TT2^=value_series_2 then do;
N_series_3=N_series_3+1; value_series_3=TT2;
DO l=k+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID3 TT=TT3)) point=l nobs=nobs3;
if TT3=value_series_3 then N_series_3=N_series_3+1;
else
if TT3^=value_series_3 then do;
N_series_4=N_series_4+1; value_series_4=TT3;
DO m=l+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID4 TT=TT4)) point=m nobs=nobs4;
if TT4=value_series_4 then N_series_4=N_series_4+1;
else
if TT4^=value_series_4 then do;
N_series_5=N_series_5+1; value_series_5=TT4;
DO n=m+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID5 TT=TT5)) point=n nobs=nobs5;
if TT5=value_series_5 then N_series_5=N_series_5+1;
else if TT5^=value_series_5 then do;
End_run=1;end;
END;END;END;END;;END;END;END;END;END;
run;
A few questions:
Regards Peter.
Hi,
I want to do it for all rows in the table.
The column is series1_valueand the value in this column for the first row is 500.
Thanks,
HHC
So I do nested loop to count the series of number (TT) with the same value.
The basic idea is:
Start with 1st row. Keep TT value in value_series_1
.
Loop to next row, if TT is the same as value_series_1
increase the N_series_1
by 1. If not the same, it is the start of value_series_2
My code below work with lookback=12. It gives correct result for the first few rows but then at rows 8, number look weird with the N_series inflated to 30+.
Same thing when lookback=4, the error show right on the first row.
Look like the script doesn't stop at i+&lookback
DO j=i+1 to i+&lookback until (End_run=1);
I can't find the problem and really appreciate it if you could help.
Thanks,
HHC
data have;
input ID TT;
datalines;
1 500
1 500
1 3
1 3
1 3
1 -3
1 -3
1 -500
1 500
1 -5
1 -500
1 3
1 3
;run;
%let lookback=5;
data want;
set have;
drop i End_run ID1-ID5 TT1-TT5;
i+1;
End_run=0;
N_series_1 = 0; value_series_1 =0;
N_series_2 = 0; value_series_2 =0;
N_series_3 = 0; value_series_3 =0;
N_series_4 = 0; value_series_4 =0;
N_series_5 = 0; value_series_5 =0;
N_series_1 = 1; value_series_1 =TT;
DO j=i+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID1 TT=TT1)) point=j nobs=nobs1;
if TT1=value_series_1 then N_series_1=N_series_1+1;
else
if TT1^=value_series_1 then do;
N_series_2=N_series_2+1; value_series_2=TT1;
DO k=j+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID2 TT=TT2)) point=k nobs=nobs2;
if TT2=value_series_2 then N_series_2=N_series_2+1;
else
if TT2^=value_series_2 then do;
N_series_3=N_series_3+1; value_series_3=TT2;
DO l=k+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID3 TT=TT3)) point=l nobs=nobs3;
if TT3=value_series_3 then N_series_3=N_series_3+1;
else
if TT3^=value_series_3 then do;
N_series_4=N_series_4+1; value_series_4=TT3;
DO m=l+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID4 TT=TT4)) point=m nobs=nobs4;
if TT4=value_series_4 then N_series_4=N_series_4+1;
else
if TT4^=value_series_4 then do;
N_series_5=N_series_5+1; value_series_5=TT4;
DO n=m+1 to i+&lookback until (End_run=1);
set have(keep = ID TT rename =(ID=ID5 TT=TT5)) point=n nobs=nobs5;
if TT5=value_series_5 then N_series_5=N_series_5+1;
else if TT5^=value_series_5 then do;
End_run=1;end;
END;END;END;END;;END;END;END;END;END;
run;
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