petascope - wrong error for scaling if axis label does not exist in coverage

[Bang Pham Huu]

For example, if a coverage's geo CRS is in EPSG:31467 with X and Y axes. But, a WCPS query contains Lat axis:

for c in (o2_4G_5G_Homespot_800) return
encode(scale(c, { Lat:"CRS:1"(0:1000) }), "jpeg")

the error is:

Index 1 out of bounds for length 1

[Dimitar Misev]

But also a more generic error, which is also wrong, is shown:

Cannot connect to petascope, please make sure that petascope is running.