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From |
Diego Bellavia <messadua@yahoo.it> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: Summarizing data by Timestamps |

Date |
Mon, 7 Dec 2009 19:44:38 +0000 (GMT) |

Great !! It sounds perfect to me, I will give it a try and let you know. Thanks a bunch : ) Diego --- Lun 7/12/09, Eric Booth <ebooth@ppri.tamu.edu> ha scritto: > Da: Eric Booth <ebooth@ppri.tamu.edu> > Oggetto: Re: st: Summarizing data by Timestamps > A: statalist@hsphsun2.harvard.edu > Data: Lunedì 7 dicembre 2009, 20:19 > >< > > > > Diego: > > I added some extra timestamps since you were interested in > time periods of a couple of hours: > > > **** > clear > > input str20 timestamp > pressure > "11/22/09 00:00" 120 > "11/22/09 00:01" 123 > "11/22/09 00:02" 119 > "11/22/09 00:03" 115 > "11/22/09 00:09" 123 > "11/22/09 00:10" 122 > "11/22/09 00:22" 112 > "11/22/09 01:20" 2000 > "11/22/09 01:27" 2100 > "11/22/09 05:27" > 5000 > "11/22/09 06:45" > 10000 > end > > *format timestamp %tCNNDDYY_HH:MM > g double timestamp2 = clock(timestamp, "MD20Yhm") > > **avg. by one hour interval** > g hour = hh(timestamp2) > egen one_hour_avg = mean(pressure), by(hour) > > **take averages for different time periods from 1:00** > forv t = 2(1)6 { > egen hour_avg_`t' = mean(pressure)if hour<=(1+`t') & > hour>=1 > } > > **or by collapse to get summary info by hour, etc** > preserve > collapse (mean) pressure , by(hour) > li > restore > ***** > > > ~Eric > __ > Eric A. Booth > Public Policy Research Institute > Texas A&M University > ebooth@ppri.tamu.edu > Office: +979.845.6754 > > > > On Dec 7, 2009, at 12:51 PM, Diego Bellavia wrote: > > > Hello StataListers, > > > > I have such a dataset: > > > > Timestamp > Pressure > > 11/22/09 00:00 120 > > 11/22/09 00:01 123 > > 11/22/09 00:02 119 > > 11/22/09 00:03 115 > > 11/22/09 00:09 123 > > 11/22/09 00:10 122 > > 11/22/09 00:22 112 > > > > etc... > > > > As you see, Pressure values are reported by time > (defined as a timestamp) every minute. > > Unfortunately, the system is not so precise to collect > pressure every single minute so, > > I do not necessarily have 60 measures in 1 hour. > > Now I would like to compute averages for Pressure > every pre-spcified time range, starting, as exmaple, > > with ana average of all the values collected between > 00:00 and 01:00 on 11/22/2009 but also being able to > > change the time range from 1 hour, to 4 or 6 hours and > so on. > > > > How can I do that in STATA, considering that I do not > know how many measure are collected per hour ? > > > > Thank you in advance, > > > > Diego > > > > > > > > > > > > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/statalist/faq > * http://www.ats.ucla.edu/stat/stata/ > * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/

**References**:**Re: st: Summarizing data by Timestamps***From:*Eric Booth <ebooth@ppri.tamu.edu>

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