Graphene derivative is used to convert the difference between values for a certain time into a value delta. It's a bit awkward but works and it is an uncommon operation.
Normally this just returns the deltas, but for some weird reason it also skips null values. This can result in a graph showing lower values than they should, which is especially confusing to new users.
There is another function that can change the semantics of nulls called keepLastValue. It works almost always, but it can result in a graph sometimes showing no data at all if the last known value is too old to be included in the requested time range.
If you have a statsd server that infrequently updates your metric and use this function, it can be a problem. This is because the statsd server will only flush a fraction of your data, so there may be gaps in the aggregation window.
You can fix this with a function called aggregateLine that consolidates the data points. This will ensure the correct data points are retained and the graph should line up correctly.
Graphene oxide (GO) is a two-dimensional crystalline graphite that contains numerous functional oxygen-containing groups. These include carboxylic acid, alcohol, and deep oxide groups. These functional groups have a wide range of applications, including biodetection and bioconjugation. GO is a product of graphite exfoliation and oxidation, which results in an increased interlayer distance and the presence of more oxygen-containing functional groups.