Counting points from layer at map extent with QGIS expression

Question

I want to create an expression in the QGIS 3.28 dashboard layer that counts points on a specific point_layer and with a specific value that is displayed in the current map_extent view

aggregate(
   layer:='point_layer', 
   aggregate:='count', 
   expression:="field1", 
   filter:="field1"='3' AND within(.. ???.. )
   )

you can use the function from this post to get the current extent as a geometry — JGH, Dec 03 '23 at 14:49
could you explain in more detail how to invoke this function inside expression ... i am not familiar with using functions — Rii Pii, Dec 04 '23 at 06:29
Please be aware you have a spelling mistake in your expression. whithin should be within. — Matt, Dec 04 '23 at 07:08
See this section of the documentation for how to define and use a custom function. — Matt, Dec 04 '23 at 07:28

score 3 · Accepted Answer · edited Dec 04 '23 at 09:09

3

The @map_extent variable returns the current extent:

aggregate(
   layer:='point_layer', 
   aggregate:='count', 
   expression:="field1", 
   filter:="field1"='3' AND within(@geometry, @map_extent)
   )

edited Dec 04 '23 at 09:09

Taras

32,823
4
66
137

answered Dec 04 '23 at 08:33

webrian

2,171
14
13

thank you webrian & Taras ... it is working well – Rii Pii Dec 05 '23 at 10:49

Counting points from layer at map extent with QGIS expression

1 Answers1