KGA Irrigation Toolsដំណើរការជាបាច់

DEM Point Sample Export to Excel

យកគំរូ DEM ចាប់ពី ២ ឡើងទៅ នៅចំណុចក្នុងក្រឡាចត្រង្គទៀងទាត់ រួចនាំចេញមួយជួរក្នុងមួយចំណុចទៅ Excel។

រកឃើញនៅឯណា
Processing ▸ Toolbox ▸ KGA Toolbox ▸ KGA Irrigation Tools ▸ DEM Point Sample Export to Excel
លេខសម្គាល់ algorithm
kga:dempointsampleexport
ប្រភេទឧបករណ៍
Batch algorithm

ទិដ្ឋភាពទូទៅ

The use case is checking agreement between elevation sources — a reference DEM plus the corrected DEMs from DEM Elevation Correction — in a spreadsheet you can sort, filter and hand to someone who does not use QGIS.

ប៉ារ៉ាម៉ែត្រ

Parameters for DEM Point Sample Export to Excel
ឈ្មោះប្រភេទតម្លៃលំនាំដើមការពិពណ៌នា
DEM layers to sample (2 or more)Multiple raster layersThe order you select them in is the column order, and the finest is used as the reference for the difference columns.
NoData overrides (comma-separated, matching DEM order)String, optionalemptyOne value per DEM, in selection order. Blank uses each raster's own NoData metadata.
Pixel stride (sample every Nth pixel)Integer (min 1)20
Max rows (Excel limit is ~1,048,576)Integer (min 1)1000000
Output file nameStringdem_point_samples.xlsx
Output folderFolder destination

របៀបប្រើ

  1. Load the DEMs to compare — the reference first is the clearest habit.
  2. Open KGA Irrigation Tools > DEM Point Sample Export to Excel.
  3. Select the DEMs, set the Pixel stride, and name the output.
  4. Press Run.
  5. Open the workbook and sort on a difference column — the largest disagreements are where the elevation sources actually conflict.

លទ្ធផល

លទ្ធផលដែលប្រកាស

Outputs declared for DEM Point Sample Export to Excel
ឈ្មោះប្រភេទការពិពណ៌នា
Exported Excel (or CSV) fileFile
Run summaryString

អ្វីដែលអ្នកទទួលបាន

One workbook in the output folder with a row per sampled point:

ColumnMeaning
X, YSample location
one column per DEMElevation there, or blank where that DEM has NoData
ZoneWhich DEMs have valid data at this point
difference columnsAgainst the finest reference DEM, and against each DEM's immediately-finer neighbour

កំណត់សម្គាល់ និងដែនកំណត់

  • Excel caps at about 1,048,576 rows per sheet. The stride is increased automatically if the requested sampling would exceed the row limit you set, so a run always produces a readable file — but the grid may then be coarser than you asked for. The run summary says what stride was actually used.
  • Very large outputs may be written as CSV instead; the declared output is named "Excel (or CSV) file" for that reason.
  • NoData overrides must match the order you selected the DEMs in.
  • A blank elevation cell means NoData at that point, not zero. The Zone column is there so you can filter to points where every DEM has data before comparing.
  • This tool only reports. It never modifies a DEM.

មើលផងដែរ

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