Thanks for the reply Simon. I've checked and the old and new sensors and they have the same 0.1 resolution but as mentioned the new sensors only send data intermittently which can be as long as every hour. I removed the (IF Undefined use Prev value) code but still have same problem. See below recent example with log data, the second image has an added black line with my expected plot.
<http://rrd-mailinglists.937164.n2.nabble.com/file/n7583588/Temp_over_4h_RRD_with_data_and_expexted_line.jpg> As mentioned this problem only happens because the data is so intermittent. thanks again for your feedback -- View this message in context: http://rrd-mailinglists.937164.n2.nabble.com/Intermittent-data-causing-stepped-graphs-tp7583586p7583588.html Sent from the RRDtool Users Mailinglist mailing list archive at Nabble.com. _______________________________________________ rrd-users mailing list rrd-users@lists.oetiker.ch https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users