Latest Contributions by DuncanHornby

‎04-10-2026

@Keith-VanGraafeiland thank you for confirming the source of the missing data is NASA and not an error in the processing chain. I still think you should update the metadata for this Authoritative dataset to say that it is incomplete and especially the team behind the aggregate tool to improve error messaging. With regards to the inputs to the aggregate tool, I point you to the comments for the dataset, you'll see I was having difficultly in preparing a subset of the data in crf format. I was not trying to directly process an image service. It is useful for others reading this idea to hammer home the input data type.

‎04-10-2026

Esri, I'm working on a project that requires me to access the chlorophyll-a living atlas dataset here. I am accessing it via the portal tab in the ArcPro catalog pane. As I wish to do some basic mean values over specific months I am using the Analytic renderer which in ArcPro says it is a log10 scale, but this hides the original pixel value. You can see the raw pixel value if you change the pop-up configuration to show it. But these values do not appear to be exposed to the aggregate multi-dimensional tool. SO when I run that tool I aggregate over the log10 values. After asking an AI I have learnt that a raster processing template is applied to transform the values to a log10 scale and the renderer shows this as 0 to 100. No doubt the mathematicians amongst you would say you can reverse engineer the transformation to get to the original chlorophyll-a concentrations but after querying AI it suggests that the common equation used has a gain/offset value which it took a best guess at. I show the response of the AI below but there is no information I can find in the metadata of this Authoritative dataset that describes the exact processing template and the functions used with their settings. So my question is simply what are the raster processing functions applied to the chlorophyll-a data? In what order and what are the settings? I need to reverse engineering this log scale to see the real values for my colleagues analysis to continue. The AI response was this: 2. The Conversion Formula In many oceanographic and satellite products (like those from MODIS or Sentinel), the relationship between the Raw Pixel Value (PV) and the Physical Value (V) follows a specific linear-log transformation. The most common formula used in these analytic renderers is: V = 10^(a . PV + b) Where: PV: The raw service pixel value (0.207422) a: A scaling slope (often 6.75 or 7.0 in standard ocean color products) b: An offset (often -0.9 or -1.0) Let's test the math: If we plug your values into a standard scaling used by many Chlorophyll-A services: Scale the raw value: (6.75 * 0.207422) + 0.05 = 1.4501 Apply the Power of 10: 10^1.4501 = 28.19 Your result of 27.4969 is remarkably close to this. The slight difference comes down to the specific Gain and Offset parameters defined in the metadata of your specific raster service.

‎03-30-2026

I would like to see a new button or menu option that clears all selection on ALL maps in one go. To me it make sense that it becomes an option in the context menu when you click on the maps node in the catalog pane as I show below, but if esri wisdom see fit to place it elsewhere that's fine. Why would I want this? I am using the presentation mode built into arcpro. During rehearsing I click on map(s) and introduce a selection. In a multi-map project, which one would expect if using presentation mode, it become tedious to enter each map to clear the selections on one or more layers so the presentation is left ready to go. It would be good to have a button that instantly clears all selections on layers/tables in all maps.

‎03-27-2026

@BBicking1 - Much appreciated!

‎03-27-2026

I've just wasted hours of my life because this tool does not return a helpful error message. I was trying to aggregate chlorophyll-a data in this living atlas multidimensional datasets. I'm aggregating over user defined time ranges and the tool bombs out returning this error message Failed to execute. Parameters are not valid. ERROR 000800: The value is not a member of 2002-07-04T00:00:00 | 2002-07-05T00:00:00 | 2002-07-06T00:00:00 | 2002-07-07T00:00:00 | 2002-07-08T00:00:00 | 2002-07-09T00:00:00 | 2002-07-10T00:00:00 | 2002-07-11T00:00:00 | 2002-07-12T00:00:00 | 2002-07-13T00:00:00 | 2002-07-14T00:00:00 | 2002-07-15T00:00:00 | 2002-07-16T00:00:00 | 2002-07-17T00:00:00 | 2002-07-18T00:00:00 | 2002-07-19T00:00:00 | 2002-07-20T00:00:00 | 2002-07-21T00:00:00 | 2002-07-22T00:00:00 | 2002-07-23T00:00:00 | 2002-07-24T00:00:00....... Now you might say, well its obvious, one of your parameters is not in the date list. Well I'm being very kind to you by not showing you the 4000 or so other lines in this error message! Every date since July 2002! So the error message says my date is not in list of valid values, but which is it!!!! The tools error message needs to state at the top which input value is missing from the accepted list not just say a value is missing. Multidimensional datasets are very large! I've had to spend several hours to track down that the multidimensional data is actually missing some dates and it was just really bad luck for me that I happen to have chosen one of these missing dates. I hope someone from esri contacts the oceans team and points this out to them, as users need to be made aware that this dataset that is an an Authoritative dataset on living atlas is actually incomplete! For the record I discovered that 2020-06-29 and what was the killer for me 2020-07-01 are missing, there may be more?

‎03-20-2026

@vanesch I clicked on your link out of interest but AGOL blocks it as it appears you are not sharing it.

‎03-20-2026

Yeah I definitely will zoom into your red box limits and you are right I would still like to see an arrow. So I think my "80% position" is actually 80% of the displayed line. So when zoomed out and viewing the whole line 80% is the 80% position, but when zoomed into a junction and lets say you are viewing 50% of the actual line then my 80% position now becomes 80% of 50% of the line...my brain hurts! So the arrow dynamically moves. I think having the user choose a position and default could be mid-point is a good solution as may be you have some sort of symbology that actually places a symbol marker at the mid point of the line. In that case a user might say show the arrow at the 25% position so it does not clash with their symbol?

‎03-20-2026

@DanLee I do a lot of work with river networks, so I dream about nodes and lines! 😁 Reading your comment about a distinguishable symbol designs for nodes, I feel that might be problematic as in rivers you can have nodes where for example two lines flow in, 3 lines flow out and 1 line starts and ends at the same node (i.e. loops) and probably a bunch of other nutty scenarios. So I'm leaning to your idea that the direction is best symbolised with an arrow along its length. Although what you say about it being a mid-point location as that is conceptually easier to understand, I as someone who stares at rivers all day think there may be merit in a to-end position. So below is me using a standard arrow symbol at 50% along length of line. I've made nodes and dangles as solid circles (its what I like). 50% along This is me fudging an 80% along symbol, I just prefer it, although difference in minimal? But having the ability to flash on/off an arrow would be very useful. 80% along

‎03-20-2026

@DanLee That is a very good point with the overlap issue. I think what is good about the new node and vertices display option is that its temporary, with a click of a button you can turn the display on and off without altering the symbology of the data, it does not require a selection or definition query. You simply display the vertices and then turn them off. So my idea is as you rightly point out only suitable for non-connecting lines. If the display option can display a simple arrow along the line that can be turned off as easily as the vertices then that would resolve the overlap issue. Now what might be a clever display is if the arrow is closer to the to-end of the line (say 80% along length of line) rather than mid-point. I'm thinking if you have hundreds of lines displaying its very position subtly tells you which end of the line you are looking at. I suspect esri would need to do a little research on what works for people?

‎03-18-2026

ESRI introduced the ability to display vertices and nodes which is a useful addition to ArcPro. But I would like to see 1 more symbology option for LINES and that is to symbolize the start and end vertices in a different colour. When you edit the vertices of a line you can identify the direction of the line as the end vertex is red. BUT the edit vertices tool only shows this 1 line at a time, the currently selected line. I would like to see the vertices of multiple lines (all features in the layer) so I can make a judgment call. Yes I could change the symbology of the line to have an arrow indicating direction but I don't want that I want to use the new nifty symbolize vertices/nodes option. A quick flick on 'n' off to show me the bulk of the data's direction. As a use case scenario I'm measuring transects from the coast out to sea and I need the data to be directed out to sea. Flicking on nodes with start/end colouration would be a nice, fast solution.

‎03-18-2026

I built a tool in RivEX that would identify and remove collinear vertices in a river network, help file is here. But this is expecting a river network not a utility network. I used the slope approach. I'm sure you could put some code together to loop over your lines searching for collinearity.

‎03-16-2026

As you have posted your question in the ArcPro group I will assume you are seeking an Arcpro solution. Simply add the 2 layers to your map and run the Add Spatial Join tool and make sure Permanently Join Fields is checked on if you want the field from your polygon dataset to be permanently transferred into your point dataset.

‎03-13-2026

Good news got the tool working with help from @Aote_Xin ! So lessons learned. 99999 errors are not very helpful particularly when I (yes it was me who was at fault) made a blunder in my choice of DEM. I'm hoping that esri will improve the error reporting of the tool and the usage advice in the help file so other future users don't make the same mistake as me. So only when @Aote_Xin provided a DEM that worked were we able to see that basically I had downloaded an inappropriate dataset for the tool. I had downloaded a NASADEM from here. This is not an elevation dataset! After digging around in their user guide table 1 on page 3 I determined the NASADEM_SIM was incorrect and I should have been using their NASADEM_HGT. The NASADEM_SIM is an 8bit 0-255 value raster the sort you might use for a grey scale display. The NASADEM_HGT is an integer raster and appropriate for the Extract water tool. Also it seems to be best practise but not enforced that the DEM extent should enclose the extent of the SAR dataset. With a correct DEM and following the sequence: Apply Radiometric Calibration (Gamma Nought) Apply Radiometric Terrain Flattening Extract Water runs successfully. So where does one source correct DEMS? You could, as I had, go to the primary portal such as EARTHDATA but an alternative worthy of mention is https://opentopography.org/ It's worth mentioning that the YouTube video above gives one the impression that the tool runs super fast, that is definitely not the case for me on an i7, 32GB machine it took about 6 minutes and tinkering around with the minimum area parameter can significantly increase processing time. When you finally get it to run its pretty awesome! 😁

‎03-09-2026

Thanks for this pointer, that google document looks helpful. I'm keen to hear back from @Aote_Xin as I would like to keep the workflow "simple" with a single call to the extract water tool before I explore writing custom code to generate Otsu thresholding. Interesting though.

‎03-06-2026

@Aote_Xin Here is a temporary link to the Source SAR data, I will remove it in a week as its swallowing up my allowance on dropbox! https://www.dropbox.com/scl/fi/buezphrq19miovxe4pypq/S1A_IW_GRDH_1SDV_20200209T110313_20200209T110342_031175_03959E_A378_COG.SAFE.zip?rlkey=ibfado9ahefvkxoin4ftwf70o&dl=0 For the record the DEM I had been using is the NASADEM which I sourced here. Also I tried your recommendation take the source SAR (the manifest.safe) and add to map, run that through the Apply Radiometric Calibration (Gamma Nought) then the extract water and it still gives an instant 999999 error. I remember trying the feature detection wizard, it would step through the pre-processing steps and fail on the extract water from what I remember. So I moved to running the individual geo-processing tools so I could follow the sequence and see if there were any warnings (there were none).

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My Ideas

Latest Contributions by DuncanHornby

Re: Improve error message in Aggregate Multidimensional Raster tool

What are the raster functions applied to the living atlas chlorophyll-a data?

Add the ability to clear all selections on all maps in a project

Re: Improve error message in Aggregate Multidimensional Raster tool

Improve error message in Aggregate Multidimensional Raster tool

Re: Limit or Disable Drag and Drop from Catalog

Re: Add start and end symbology to vertices and nodes display option

Re: Add start and end symbology to vertices and nodes display option

Re: Add start and end symbology to vertices and nodes display option

Add start and end symbology to vertices and nodes display option

Re: Automating the removal of redundant vertices on Arcs (Utility Network errors)

Re: How to write polygon value to point feature class based on geometric intersection

Re: Any help with using the SAR extract water tool?

Re: Any help with using the SAR extract water tool?

Re: Any help with using the SAR extract water tool?

Re: Dissolve polygons only within a given distance...

Re: How do I remove purple border around chart?

Re: How do I remove purple border around chart?

Re: Wayback imagery and wayback metadata do not ta...

Re: Wayback imagery and wayback metadata do not ta...

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