topic Re: Generating Random Numbers in SAS Procedures

Generating Random Numbers

deleted_user — Wed, 18 Aug 2010 14:21:30 GMT

Is there a function that will generate a random number with decimal places within a certain range?

For example, I need to generate a random number between -12.345 and 67.890. This number must have 3 decimal places, and can be positive or negative, as long as it's within the range given.

Much obliged! 🙂
Suzy

Re: Generating Random Numbers

RickM — Wed, 18 Aug 2010 14:44:21 GMT

Something like this would work.

var=round(ranuni(0)*(12.345+67.890),0.001)-12.345;

To generalize it you would need to create a macro or use proc fcmp.

Re: Generating Random Numbers

deleted_user — Wed, 18 Aug 2010 14:58:26 GMT

Thank you, Rick, that's awesome!

Suzy

Re: Generating Random Numbers

sbb — Wed, 18 Aug 2010 16:10:21 GMT

Future reference, consider searching the SAS support http://support.sas.com/ website which has SAS-hosted product documentation and supplemental technical / conference reference material.

Scott Barry
SBBWorks, Inc.

Suggested Google advanced search argument, this topic/post:

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Re: Generating Random Numbers

Rick_SAS — Wed, 12 Oct 2011 13:09:24 GMT

See also my blog post, "How to generate random numbers in SAS."

Re: Generating Random Numbers

Howles — Wed, 12 Oct 2011 21:04:17 GMT

Note that this approach makes the endpoints of the range half as likely to be realized as the internal points.

Rick Wicklin's blog post looks at continuous ranges and integer ranges; here we have non-integer but discrete ranges.

RickM wrote:
Something like this would work.  
var=round(ranuni(0)*(12.345+67.890),0.001)-12.345;
To generalize it you would need to create a macro or use proc fcmp.

Re: Generating Random Numbers

ayecon0325 — Sat, 21 Sep 2013 06:35:38 GMT

Hi Rick! Do you a sample simulation code to generate multilevel data (nested data)? An example of this is a cluster-randomized trial (CRT) design where the treatment is implemented at the group level while the outcome is measured at the individual level?

Thanks,

Aye

Re: Generating Random Numbers

Rick_SAS — Tue, 24 Sep 2013 13:24:37 GMT

There are examples like this in my book Simulating Data with SAS. For example, see Section 7.5 and Section 11.3.