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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>You may not want interpolation, but you’re getting it. All RRD data are normalised to fit in with the interval steps, and you cannot switch this off because of the way the RRD is structured.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>If you want to avoid this, then ensure your data are submitted with a timestamp exactly on the interval boundary – IE, if your interval is 600s, then (timestamp mod 600) should be zero if you want to make normalisation a null operation.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Steve Shipway<o:p></o:p></span></b></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>s.shipway@auckland.ac.nz<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div><p class=MsoNormal><span style='font-family:"Courier New";color:black'><o:p> </o:p></span></p></div></div></div></div></body></html>