I'm relearning GIS after a ten year gap and, just like when I first learnt it, it's doing things randomly that I can't solve. Google hasn't thrown up any answers. I'm trying to do some interpolation in QGIS 3.1- I did it yesterday following the instructions in this video -
Now, two days later, it won't play ball. I do the interpolation and either there's no output or a single colour output using an average value of the data I'm interpolating between.
Here's what I'm doing-
1- I have five data points showing levels of an element in groundwater. I want an interpolation between them.
[url= https://live.staticflickr.com/65535/49362636291_7a373ec203.jp g" target="_blank">https://live.staticflickr.com/65535/49362636291_7a373ec203.jp g"/> [/img][/url][url= https://flic.kr/p/2id1q14 ]1[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
2- Here's the attribute table for the field-
[url= https://live.staticflickr.com/65535/49362844752_32f7e60afa_w.jp g" target="_blank">https://live.staticflickr.com/65535/49362844752_32f7e60afa_w.jp g"/> [/img][/url][url= https://flic.kr/p/2id2tYd ]2[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
3- Here's what I've put into the IDW Interpolation box-
[url= https://live.staticflickr.com/65535/49362173293_217a23b172_z.jp g" target="_blank">https://live.staticflickr.com/65535/49362173293_217a23b172_z.jp g"/> [/img][/url][url= https://flic.kr/p/2icY3nk ]3[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
4 - The output interpolation layer only has a single value. Changing this value in the Style dialog box doesn't do anything - the interpolation visualisation doesn't display.
[url= https://live.staticflickr.com/65535/49362173263_2c4c43428f_n.jp g" target="_blank">https://live.staticflickr.com/65535/49362173263_2c4c43428f_n.jp g"/> [/img][/url][url= https://flic.kr/p/2icY3mP ]4[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
5 - Here's what my map looks like after I've run the interpolation. Nothing.
[url= https://live.staticflickr.com/65535/49362173228_408b454511_z.jp g" target="_blank">https://live.staticflickr.com/65535/49362173228_408b454511_z.jp g"/> [/img][/url][url= https://flic.kr/p/2icY3md ]5[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
If I run it using Layer Extent as the area - a black square (using singleband grey for the style) -
[url= https://live.staticflickr.com/65535/49362882777_1f9c8905cb_z.jp g" target="_blank">https://live.staticflickr.com/65535/49362882777_1f9c8905cb_z.jp g"/> [/img][/url][url= https://flic.kr/p/2id2FgP ]6[/url] by [url= https://www.flickr.com/photos/183377889@N06/ ]Luke Bradley[/url], on Flickr
What am I doing wrong? I've not changed anything from when I ran this on Wednesday and got a lovely colourful display using singleband pseudocolour.
Is the CRS of your map layer set to EPSG:27700 (bottom right next to Render)
Is it because value 5 is selected in the attribute table?
Oooh a nice juicy contaminated site.
Dye works?
What have you changed?
Reimported the points?
Altered the CSV?
I don't have an answer, but I applaud your ability to beautifully form a question.
Is it pronounced jizz???
Bit of a wild card, but are you using the same monitor? It shouldn't affect the generation of the output raster, but I wouldn't rule it out.
It's not a display issue, the black raster generated is because the pixels all have the same value.
In screenshot 4 you can see the min and max of the Raster displayed under the layer (505.002 and 505.002)
I don't have quite the same version of QGIS, but it should just be as simple as following the steps the OP has included.
Does the log window shed any light?