title: Aggregate Time Series
body: <p>I have a time series class that plots each daily value (river discharge) over the date range from 2012-01-01 through 2014-02-03. I want to remove seasonal variation by applying the aggregate() function but cannot find the correct syntax for the frequency parameter.</p>
  
  <p>A sample of the data (with 2 variables) was created with dput:</p>
  
  <pre><code>structure(c("2014-01-01", "2014-01-02", "2014-01-03", "2014-01-04", 
  "2014-01-05", "2014-01-06", "2014-01-07", "2014-01-08", "2014-01-09", 
  "2014-01-10", "2014-01-11", "2014-01-12", "2014-01-13", "2014-01-14", 
  "2014-01-15", "2014-01-16", "2014-01-17", "2014-01-18", "2014-01-19", 
  "2014-01-20", "2014-01-21", "2014-01-22", "2014-01-23", "2014-01-24", 
  "2014-01-25", "2014-01-26", "2014-01-27", "2014-01-28", "2014-01-29", 
  "2014-01-30", "2014-01-31", "2014-02-01", "2014-02-02", "2014-02-03", 
  "2014-02-04", "2014-02-05", "2014-02-06", "2014-02-07", "2014-02-08", 
  "2014-02-09", "2014-02-10", "2014-02-11", "2014-02-12", "2014-02-13", 
  "2014-02-14", "2014-02-15", "2014-02-16", "2014-02-17", "2014-02-18", 
  "2014-02-19", "2014-02-20", "2014-02-21", "2014-02-22", "2014-02-23", 
  "2014-02-24", "2014-02-25", "2014-02-26", "2014-02-27", "2014-02-28", 
  "2014-03-01", "2014-03-02", "119000", "125000", "129000", "125000", 
  "122000", "155000", "157000", "152000", "156000", "156000", "106000", 
  "147000", "123000", "123000", "128000", "150000", "135000", "135000", 
  "134000", "144000", "154000", "152000", "139000", "147000", "135000", 
  "120000", "119000", "124000", "132000", "152000", "138000", "140000", 
  "137000", "133000", "126000", "102000", " 82900", "133000", "158000", 
  "116000", "145000", "151000", "125000", "130000", "116000", "137000", 
  "133000", "129000", "128000", "126000", "135000", "136000", "153000", 
  "172000", "4.5", "4.6", "4.6", "4.5", "4.4", "4.3", "4.4", "4.4", 
  "4.4", "4.4", "4.5", "4.5", "4.5", "4.5", "4.5", "4.4", "4.3", 
  "4.3", "4.4", "4.4", "4.4", "4.5", "4.5", "4.4", "4.3", "4.3", 
  "4.2", "4.1", "4.0", "4.0", "4.0", "4.0", "3.8", "3.7", "3.5", 
  "3.3", "3.0", "2.8", "2.6", "2.5", "2.5", "2.5", "2.5", "2.6", 
  "2.7", "2.5", "2.4", "2.7", "2.9", "2.8", "2.9", "3.1", "3.2", 
  "3.3", "3.4", "3.4", "3.5", "3.7", "4.0", "4.2", "4.1"), .Dim = c(61L, 
  3L), .Dimnames = list(NULL, c("date", "disch", "temp")), .Tsp = c(1, 
  61, 1), class = c("mts", "ts", "matrix"))
  </code></pre>
  
  <p>When I try to aggregate (on only the disch data for the entire time period) my choice of frequency (which is 365 for the ts object) produces a blank plot. The syntax I use is:</p>
  
  <pre><code>plot(aggregate(dalles.disch.ts, FUN=mean, freq=365)
  </code></pre>
  
  <p>Reading ?ts there are examples for monthly data but not daily. Since I have daily data for all of 2012 and 2013 plus the first two months of 2014, what FUN and freq should I speciry?</p>