Feature request #9124
Heatmap in percentage
Status: | Rejected | ||
---|---|---|---|
Priority: | Normal | ||
Assignee: | - | ||
Category: | Analysis library | ||
Pull Request or Patch supplied: | No | Resolution: | invalid |
Easy fix?: | No | Copied to github as #: | 17761 |
Description
Heatmaps would be far more convenient (easier to interpret in many contexts) if they could (optionally) be expressed in % rather than in absolute values (in inverse values, so one could create isolines including, say, 95% probability). The change seems trivial:
- calculate the maximum
- dividing the raster values by that
- adding an option to choose between absolute values and %
Also a note on the help on how to interpret cell values would make life easier for newbies.
History
#1
Updated by Nyall Dawson about 11 years ago
It's actually not quite that simple - the maximum value is not known until the entire heatmap is generated, it can't be calculated in advance.
The actual process would be:
1. Generate the heatmap
2. Scan for the max and min values within the heatmap (The minimum value would also need to be considered, since points could potentially have a negative weighting set resulting in raster values < 0)
3. Update the cell values with a value relative to the max/min values
I'm wondering if it would be better/more flexible for this to be done via a step in a processing script. Problem is that heatmaps can't be generated via scripts at the moment - this would require moving the heatmap code from a c++ plugin to core (something which should be done at some time in any case). This is on my (distant) radar, alongside adding additional hotspot types such as Getis Ord Gi*. I'm hoping to get funding or some time of sponsorship to tackle this.
#2
Updated by Jürgen Fischer about 11 years ago
- Subject changed from Heathmap in percentage to Heatmap in percentage
#3
Updated by Matthias Kuhn about 11 years ago
Alternative for moving to core:
We could add the possibility to expose a python API from C++ plugins as well. I could provide some code I have written for globe which does exactly this.
#4
Updated by Jürgen Fischer over 10 years ago
- Category changed from C++ Plugins to 114
#5
Updated by Giovanni Manghi about 8 years ago
- Category changed from 114 to Analysis library
#6
Updated by Giovanni Manghi about 8 years ago
- Target version set to Version 3.0
#7
Updated by Giovanni Manghi almost 8 years ago
- Easy fix? set to No
#9
Updated by Nyall Dawson almost 7 years ago
- Status changed from Open to Feedback
I think this should be closed, and replaced with a feature request for a processing algorithm which scales raster values to percent of max.
Heatmaps are part of processing now, so only the scaling algorithm is missing from this request.
#10
Updated by Paolo Cavallini almost 7 years ago
- Resolution set to invalid
- Status changed from Feedback to Rejected
Fully agreed.