title: Error when trying to use stl and decompose functions in R
body: <p>I have made a simple time-series, i added a little noise to a sin function and tried to decompose it using the "stl" and "decompose" function in R, while my series definitely has more than 2 period and is periodic, R gives me the following error for both functions: </p>
  
  <pre><code>x
    [1]  1.4537365796  2.7185844368  2.8394728999  3.8926989923  4.3405508086  5.1959080871
    [7]  5.6602505790  5.4829985648  5.6357660330  4.6084976233  4.6617322922  4.0286486832
   [13]  3.3641752333  1.7408063182  0.8815147612  0.2895139342 -0.5402768515 -1.5612641107
   [19] -2.1584502547 -2.9878043526 -3.5545638149 -4.0530074199 -4.0748538612 -4.7581704662
   [25] -4.6555349052 -4.0726206240 -3.1646413472 -2.6934453823 -2.2364605277 -1.2643569882
   [31] -0.1202011946  1.1136371449  2.2504199271  3.0313528996  3.5384449109  4.5176211013
   [37]  5.4013172839  5.4252837451  5.4768196692  5.8979709077  5.6698285659  4.5133489450
   [43]  4.2702602998  3.5180837069  2.2652913344  1.1975595698  0.5412697849 -0.5966162032
   [49] -1.0827728340 -1.8488242277 -3.4118061838 -3.9009752140 -3.9102671954 -4.3486102172
   [55] -4.7481017993 -4.0097598695 -3.9078554267 -3.8070416888 -2.5968567322 -2.2567568949
   [61] -1.1423907008  0.0002492447  0.4338279080  1.2431986797  2.3216397323  3.3235925116
   [67]  4.1591487169  4.9028481873  5.4535861470  5.0579349546  5.1548777627  4.9707124992
   [73]  5.4496833187  4.4563072487  4.1301372986  2.4594352788  1.7253019929  0.6961453965
   [79]  0.4281167695 -1.3152944759 -1.8645880957 -2.5764132038 -3.7681528112 -4.3731672862
   [85] -3.9940201611 -4.5497596299 -4.9496796983 -4.1233093447 -3.7759837204 -3.3359027749
   [91] -2.3518009102 -1.7488933797 -0.7225148838  0.5395759836  1.0496249652  2.0383715782
   [97]  3.2357449979  3.8028316517  5.0346866280  5.2154265148
  
  fit&lt;- stl(x, t.window=15, s.window="per", robust=TRUE)
  Error in stl(x, t.window = 15, s.window = "per", robust = TRUE) :series is not periodic or has less      than two periods
  
  fit&lt;- decompose(x,type="multiplicative")
  Error in decompose(x, type = "multiplicative") :time series has no or less than 2 periods
  </code></pre>
  
  <p>Would someone help me with this problem please? </p>