Thank you for the additional informations.
Excluding the ‘0’ values effectively exclude them for the data grabbed by the query. I’ve managed to obtain the same results as the ExcludeRange() function by using the following ‘Transform’ option in Grafana :
But I prefer the use of ExcludeRange() directly in the body of the query because it allows the use of variables ($PMU_NAME) while going through ‘Transform’ requires specifying in the object of the transformation the real name of the PMU (and loose the benefit of using variables because I can’t specify a variable name in the ‘Field’ field).
My last tests did not allow me to find how to substitute the ‘0’ values of the series with the ‘Null’ value which I think is the only way currently in Grafana to obtain the expected result (the discontinuity of the display). But the result obtained following your advice suits me well because it prevents the autoscale from imposing a range of ordinates [0-50] on me; which was the intended goal.
Regards