Get hour and minutes of the (current time minus 20 second) into macro variables?

[hhchenfx]

Hi,

I want to put hour and minute of the time 20 second before current time into macro variable.

The code below might convey my idea better.

Can you please help?

Thanks,

HHC

%let now=%sysfunc(time()       MINUS 20 SECOND);
%let hh=%sysfunc(hour(&now),z2.);
%let mm=%sysfunc(minute(&now),z2.);

%put &hh &mm;

[Astounding]

Have you tried

%let now = %sysfunc(time() ) - 20;

The other statements probably figure out to perform the math without even adding %eval

[PeterClemmensen · Accepted solution]

@Astounding I think you forgot to evaluate the expression. Otherwise, the - 20 part is just text.

%let now = %sysevalf(%sysfunc(time()) - 20);

%put &=now.;

[Astounding]

I didn't worry about the text, since I expected the subsequent functions could utilize that text. What I do worry about is the first 20 seconds after midnight, and whether greater care would be needed to calculate properly. I can't check this sort of detail since it has been 4 years now that I have used a computer that actually has SAS on it.

[hhchenfx]

I did try -20 and SAS give following error.

I should have included it in the original post.

1627  %let now=%sysfunc(time()       - 20);
ERROR: Expected close parenthesis after macro function invocation not found.
1628  %let hh=%sysfunc(hour(&now),z2.);
1629  %let mm=%sysfunc(minute(&now),z2.);
1630
1631  %put &hh &mm;
0,z2.) 0,z2.)

[Quentin]

As shown in the log, your parentheses are wrong.

You need to use parentheses around %sysfunc(time()).  That will return a number with a decimal in it (number of seconds since midnight).  Then if you want to subtract 20 from that value, you need %sysevalf, as shown by @PeterClemmensen .

%let now=%sysevalf( %sysfunc(time()) - 20);
%let hh=%sysfunc(hour(&now),z2.);
%let mm=%sysfunc(minute(&now),z2.);
%put &=now &=hh &=mm ;

Actually, as @Astounding pointed out the %sysevalf is not essential here, as the HOUR function is happy to take an expression as its argument, so you can do stuff like:

1    %put %sysfunc(hour(3600.5-20),z2.);
00
2    %put %sysfunc(minute(3600.5-20),z2.);
59

And to answer the question about negative values, they are not a problem.  A negative value for a SAS time is seconds before midnight:

4    %put %sysfunc(hour(5-20),z2.);
23
5    %put %sysfunc(minute(5-20),z2.);
59

[Astounding]

@Quentin 

When I posted the solution originally, I had the parentheses wrong.  Probably, @hhchenfx copied that original post and didn't get notified about the correction I had made.

Still, I'm not sure what happens when we hit just after midnight.

[Quentin]

---

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@Astounding , 5 seconds after midnight time() will return 5, so 5-20 will be negative, but it works and returns 23:59.  That was what I was trying to show with this example:

4    %put %sysfunc(hour(5-20),z2.);
23
5    %put %sysfunc(minute(5-20),z2.);
59