处理股票数据,经常要对时间变量作处理,特意摘录sas.support.com的样例来学习sas的用于时间的函数.另外《DATE HANDLING IN THE SAS ® SYSTEM》一文中也有很多详细的例子。
*计算年龄;
/* Create sample data */
data birth;
input name $ bday :mmddyy10.;
datalines;
Miguel 12/31/1973
Joe 02/28/1976
Rutger 03/29/1976
Broguen 03/01/1976
Susan 12/12/1976
Michael 02/14/1971
LeCe 11/09/1967
Hans 07/02/1955
Lou 07/30/1960
;run;
/* Use the INTCK function to count the number of months between */
/* the date of birth and the current date. Divide the number of */
/* months by 12 to produce the number of years. Use the MONTH */
/* function to determine if the month of the birthday and the current */
/* date are the same. If they are, determine if the birthday has */
/* occurred this year. If it hasn't, adjust the age by subtracting */
/* one year. */
data ages;
set birth;
retain current;
if _n_=1 then current=today();
format bday current worddate20.;
age=int(intck('month',bday,current)/12);
if month(bday)=month(current) then age=age-(day(bday)>day(current));
run;
proc print;run;
*计算两个日期间的年月日数目;
data a;
input @1 dob mmddyy10.;
/* Get the current date from operating system */
tod=today();
/* Determine number of days in the month prior to current month */
bdays=day(intnx('month',tod,0)-1);
/* Find difference in days, months, and years between */
/* start and end dates */
dd=day(tod)-day(dob);
mm=month(tod)-month(dob);
yy=year(tod)-year(dob);
/* If the difference in days is a negative value, add the number */
/* of days in the previous month and reduce the number of months */
/* by 1. */
if dd < 0 then do;
dd=bdays+dd;
mm=mm-1;
end;
/* If the difference in months is a negative number add 12 */
/* to the month count and reduce year count by 1. */
if mm < 0 then do;
mm=mm+12;
yy=yy-1;
end;
format dob tod mmddyy10.;
datalines;
01/01/1970
02/28/1992
01/01/2000
02/28/2000
02/29/2000
03/01/2000
05/10/1990
05/11/1990
05/12/1990
;
proc print label;
label dob='Date of Birth'
tod="Today's Date"
dd='Difference in Days'
mm= 'Difference in Months'
yy='Difference in Years';
var dob tod yy mm dd;
run;
/*********************************************************************/
/* The following code calculates the start and end dates for */
/* daylight saving time for the years 2006 through 2009. */
/* */
/* FDOY represents the first day of the year */
/* FDO_APR represents the first day of April */
/* DST_BEG represents the first day of daylight saving time */
/* */
/* It is calculated using this syntax: */
/* intnx('week.1',fdo_apr,(weekday(fdo_apr) ne 1)) */
/* */
/* Explanation of the above syntax: */
/* - weekday(fdo_apr) returns a number between 1 and 7, */
/* which represents the day of the week, 1=Sunday and 7=Saturday */
/* */
/* - weekday(fdo_apr) ne 1) returns a 0 if the first day */
/* of April is a Sunday and 1 otherwise. */
/* */
/* - intnx('week.1',fdo_apr,(weekday(fdo_apr) ne 1)) returns a */
/* SAS date which is 0 WEEK intervals from the FDO_APR, if the */
/* first day of April is a Sunday. The WEEK.1 interval specifies */
/* Sunday as the first day of the week. */
/* */
/* OR */
/* */
/* returns a SAS date which is 1 WEEK interval from the FDO_APR, */
/* if the first day of April is not a Sunday, (using Sunday as */
/* the first day of the week). */
/* */
/* */
/* DST_END represents the end of daylight saving time and is */
/* calculated similarly to DST_BEG. */
/*********************************************************************/
data _null_;
do year=2006 to 2009;
fdoy=mdy(1,1,year);
/* For years prior to 2007, daylight time begins in the United States on */
/* the first Sunday in April and ends on the last Sunday in October. */
if year <= 2006 then do;
fdo_apr=intnx('month',fdoy,3);
dst_beg=intnx('week.1',fdo_apr,(weekday(fdo_apr) ne 1));
fdo_oct=intnx('month',fdoy,9);
dst_end=intnx('week.1',fdo_oct,(weekday(fdo_oct) in (6,7))+4);
end;
/* Due to the Energy Policy Act of 2005, Pub. L. no. 109-58, 119 Stat 594 */
/* (2005). Starting in March 2007, daylight time in the United States */
/* will begin on the second Sunday in March and end on the first Sunday */
/* in November. For more information, one reference is */
/* http://aa.usno.navy.mil */
else do;
fdo_mar=intnx('month',fdoy,2);
dst_beg=intnx('week.1',fdo_mar, (weekday(fdo_mar) in (2,3,4,5,6,7))+1);
fdo_nov=intnx('month',fdoy,10);
dst_end=intnx('week.1',fdo_nov,(weekday(fdo_nov) ne 1));
end;
put dst_beg= worddate. /
dst_end= worddate. / ;
end;
run;
/* Sample 1: Variables for date, hour, minute and seconds */
data datetime;
if _n_=1 then sdate=date();
retain sdate;
format sasdt dateampm22. bid dollar6.0;
input hr min sec bid dollar6.;
sasdt=dhms(sdate,hr,min,sec);
keep sasdt bid ;
datalines;
8 00 25 $200
8 10 14 $300
9 24 30 $400
;
run;
/* Sample 2 : Variables for date and time */
data datetime;
if _n_=1 then sdate=date();
retain sdate;
format sasdt dateampm22. bid dollar6.0;
input stime time8. +1 bid dollar6.;
/* Use zero placeholders for the H and M parameters */
sasdt=dhms(sdate,0,0,stime);
keep sasdt bid ;
datalines;
10:30:30 $450
11:49:20 $465
13:44:12 $475
;run;
data ds1;
do date='01nov2010'd to '31dec2010'd;
output;
end;
run;
/* The WEEK variable returns a value of 1 to 5 based on the number of weeks in a month
using a combination of the INTNX and INTCK functions.
Note:
The INTCK function returns the integer number of time intervals in a given
time span. By default, Sunday is the beginning of the week interval.
The INTNX function increments (either forwards or backwards) a date,
time or datetime value by a specified interval.
*/
data ds2;
set ds1;
week=intck('week',intnx('month',date,0),date)+1;
run;
proc print;
format date date9.;
run;
*finding the first business day of the mounth;
/* Create sample data */
data test;
input date :mmddyy6.;
format date date9.;
datalines;
010106
010406
041806
081806
123106
;
data getweek;
set test;
/* Use INTNX to roll DATE back to the first of the year. */
/* Pass the result as the 'start' parameter to INTCK. */
week=intck('week',intnx('year',date,0),date)+1;
/* If you are in SAS 9.1, you can use the WEEK function. */
/* The WEEK function has an optional second argument that */
/* can be used to specify whether a week starts on Sunday */
/* or Monday. For more information, please refer to the */
/* SAS NLS User's Guide. */
/* U indicates Sunday is the first day of the week */
week_function=week(date,'u');
run;
/* create sample data */
data one;
input date mmddyy6.;
format date date9.;
cards;
011509
021509
030409
;
data two;
set one;
/* advance date to the first day of the month using the INTNX function */
first=intnx('month',date,0);
/* determine the day of the week using the WEEKDAY function */
day=weekday(first);
/* if day=Sunday then advance by 1 */
if day=1 then first+1;
/* if day=Saturday then advance by 2 */
else if day=7 then first+2;
format first date9.;
proc print;
title 'First Business Day of the Month';
run;
/* Sample 1 -- Rolling dates forwards and backwards by month using the SAMEDAY */
/* parameter new in SAS 9.1. Do NOT 'roll over' to next month if */
/* the adjusted month has fewer days than the day value of the */
/* starting month. */
data _null_;
/* Test with non-leap year */
do date='27MAR2003'd to '01APR2003'd;
lastmonth= intnx('month',date,-1,'sameday');
put (date lastmonth)(=worddate.);
end;
/* Test with leap year */
put;
do date='27MAR2004'd to '01APR2004'd;
lastmonth=intnx('month',date,-1,'sameday');
put (date lastmonth)(=worddate.);
end;
put;
/* Test future dates */
do date='27JAN2004'd to '01FEB2004'd;
nextmonth=intnx('month',date,1,'sameday');
put (date nextmonth)(=worddate.);
end;
run;
/* Sample 2 -- Rolling dates forwards and backwards by month using the SAMEDAY */
/* parameter new in SAS 9.1 while allowing shifted months with */
/* fewer days to 'roll over' to the next month. */
/* */
/* The default alignment of the INTNX function is the beginning of the shift */
/* period, the first of the month in this case. If the resulting date is in a */
/* month with less than 31 days, adjust the appropriate number of days into */
/* the next month. */
data _null_;
/* Test with non-leap year */
do date='27MAR2003'd to '01APR2003'd;
lastmonth=date - intnx('month',date,0)+intnx('month',date,-1);
put (date lastmonth)(=worddate.);
end;
/* Test with leap year */
put;
do date='27MAR2004'd to '01APR2004'd;
lastmonth=date - intnx('month',date,0)+intnx('month',date,-1);
put (date lastmonth)(=worddate.);
end;
put;
/* Test future dates */
do date='27JAN2004'd to '01FEB2004'd;
nextmonth=date - intnx('month',date,0)+intnx('month',date,1);
put (date nextmonth)(=worddate.);
end;
run