Questions tagged [contour]

Contour maps depict spatially-varying values, such as elevation, by means of curves of equal value.

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Drawing contour lines of Coastal bathymetry [closed]

I am a novice ArcMap 10.4.1 user. I made a figure of the sites that I sampled in the waters around the Korean peninsula. The base-map is NASA's ocean color .nc image with units of chlorophyll mg-m3 ...
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Depth contour line using bathymetry

I am a very basic ArcMap user.loaded an ocean color .nc map in ArcMap, (the units of the map are surface phytoplankton chlorophyll mg m-3) on which i overlaid graduated symbols of some of my data. The ...
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QGIS contour layer

I have a contour layer with 50m interval for the sea and the land. I want to keep only the labels for the sea, specificaly I want to appear only the rates<=0. Do you know any expression to do that?
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QGIS Contour Vectors to Raster

I'm wanting to create a DEM from vector contours but whatever tool I use, it fails to identify the sea level contour at elevation 0. I have tried via GRASS v.to.r, QGIS tool Vector to Raster and QGIS ...
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Closing contours along boundary lines

This is what happens when I use line to polygon But I want the contour line to close along the boundary of the picture, like this I want to use contour lines to generate contour plane What should I ...
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Transform tif file to shapefile to get outer contour of area

I have the following .tif file of an area: I want to make a shapefile out of the contour of the entire area, like the red line in the image below. Is there a way to do this with QGIS? I've tried ...
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Modifying the intervals and "offset from zero" parameter for an already-created contour line layer in QGIS

I'm trying to create a simple labeled contour line layer for a topographical map in QGIS. I've created a new layer for the contours using "Raster > Extraction > Contours" on a raster ...
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Earthpy plot array and ploints on top of "plot_rgb()"

I have a Sentinel-2 image (16 bands) that I plot with earthpy.plot_rgb. I calculate a normalized index (NDSI) with its 3rd and 11th bands, which I then filter to keep only values above a specific ...
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Delete specific values for contour lines in an attribute table for deletion in line data with QGIS

Issue: I have an attribute table showing contour lines for both bathymetric and terrestrial data. As my study is entirely focused on the marine environment, I would only like my maps to show the ...
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Flipped Contour Polygons from GDAL

UPDATE # 01 : Links to related past questions: Mirrored Contours from DEM in QGIS gdal_translate creates images that are mirrored This question has been asked before, but I can't fix my personal ...
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Displaying OS Terrain 50 data in ArcMap

I'm having some trouble using OS terrain 50 data (https://osdatahub.os.uk/downloads/open/Terrain50) in ArcMap. I have downloaded it in ASCII and GML (Grid Format). I've unzipped the folder and ...
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Polygons from lines with manually completed lines using vertex tool and snapping

I have a vector layer of lines (contours) which was a model output. Some contours are incomplete due to land barriers (necessary for the model) which produces something like this I have used the ...
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Creating TIFF from Contour Lines

I need to quickly create a TIFF terrain (shades of grey terrain) from contour lines, or rather to create a GeoTIFF. In the past, I extracted vertexes from the contour lines and used that to create new ...
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Clean DEM in QGIS

I'm attempting to create a DEM in QGIS from contours using the "Rasterize (vector to raster)" function. How do I create a DEM that is clean and does not have blank spots?
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Calculate the distance between points and contour lines

Is there a way to calculate the distance between points and contour lines with a minimum elevation value ? Context: I have data from vegetation plots in island that is mostly flat, with the exception ...
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Exporting vector contour lines from 3D Map view in QGIS

Is there a way to export the contours in a 3D map view in QGIS to vectors? Here is my 3D map view.
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Extracting contours from mesh layer in QGIS?

I am writing a C++ application that loads a NetCDF file as a mesh layer. I am attempting to utilize the QgsMeshContours class to export line geometries to be appended to a memory vector layer. ...
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Contour plot over a offline map

I am trying to plot a contour plot on the offline map. My contour plot is this: import numpy as np from scipy.interpolate import griddata as gd from matplotlib import pyplot as plt y = np.linspace(...
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Clipping unnecessary areas while using Contour plugin in QGIS

I have a point shapefile with z values which I would like to create a contour file based on. I used the Contour plugin in QGIS, however, as shown below, QGIS drew contours in the areas where I don't ...
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Converting complex depth contours to polygons in sf and R

I have a large dataset of depth contours downloaded from an open database. At the time of writing, these contours appear to contain the best available continuous depth model for my region of interest. ...
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Why is QGIS contour generating tool not working with my DEM tiff file?

First a note about previous data processing. My original data (from a LIDAR scan) is a text .asc file with the internal structure looking like this: 457758.77;110272.34;353.89 457758.77;110273.34;353....
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How can you create a polygon in QGIS which covers a certain elevation range?

I am trying to isolate 3 different elevation ranges in QGIS (200-1200m, 1200-2200m, 2200-3200). I have made contour lines for each elevation but I want to make them into separate polygons so I can ...
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Digitizing topographic contours to produce DEM from it using ArcMap

I have four topographic maps spanning 60 years all of which have the same scale (1:62,500). I have digitized contours (5 feet interval, 4 contours 285, 290, 295 and 300 feet) of the same section in ...
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Creating just one Contour line based on one spot in QGIS

The project I'm working on contains a map with different spots. Each spot has the water level [m] as an atribute. Now, I would like to create Contour lines in some spots. I know, how it works to ...
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Creating Contour Lines in QGIS 3.16 with a distance of 0,10 m

I would like to create Isohypses (Shape) ("Create contour lines") with a distance of 0,10m in a Digital Terrain Model (Shape File). While processing the command, there are some errors poping ...
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How to crop a shapefile with another shapefile with contour

I'm new using QGIS (version 3.22) and I think my doubt is simple, but I didn't find any answer. I have a vector shapefile from Brazil like this: https://geoftp.ibge.gov.br/organizacao_do_territorio/...
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Custom contours on DEM [closed]

I've made a DEM using LIDAR, and I'd like to mark specified contours on it as polylines. Is there a way I can create custom contours for specific heights OD? I can use either QGIS or ArcGIS Pro to do ...
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Automatically calculating value (point feature) between contour line (drawn by user) using ArcMap [closed]

I want to extract the value of a point from the contour line, which is shown in the below picture. Let me clarify a bit. I don't have the source raster or lidar. The contour line is basically drawn by ...
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Is it correct to use a 1/3 arc-second DEM to make a 2 ft contour shapefile?

I need 2ft contours for all of Puerto Rico. I have downloaded 1/3 arc-second DEM on the island from the USGS. Would it even be accurate I if I just made these in ArcGIS Pro? All alternatives and ...
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Labeling contour lines in ArcGIS Pro when contour lines are raster data

I am running ArcGIS Pro 2.8 on Windows 10. I have a DEM from which I am generating contour lines. In the map layout, I would like to have every 5th line labeled with the elevation value. When I use ...
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Elevation contour lines with footage calls

Does anyone know how to create contour elevation lines? I've never done it before as I am using ArcGIS 10.8. I am unable to find any datasets online for my AOI. Is this possible?
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Calculating the area individually enclosed by multiple contour lines in R (SpatialLinesDataFrame)

Aim Calculating the area and perimeter of each individual contour line (SpatialLinesDataFrame) extracted using raster::rasterToContour(). Issue In spite of my web searches, I seem I cannot find a ...
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Batch Processing Contour Lines in QGIS

I'm trying to create contour lines at 40 meter intervals from 60 different DEM Contour Shaded files. Rather than doing them 1 by 1 I have tried using the batch process but I don't get any results as I ...
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Whitebox tool not in QGIS 3.16.5

In QGIS 3.16.5 I can not see a whitebox tools to create contour from raster. Why the whitebox tool does not appear in my QGIS version?
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Topo-to-raster/anudem, entering lake polygons with elevation values

I am entering lake polygons that have elevation values as "Contour" input to topo-to-raster which I thought was correct, the documentation says: "If the elevation of the lake is known, ...
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gdal_contour: Specifying index contour lines

I'm building an application where I need to programmatically generate contour lines(and export to a .dxf) from a raster terrain data-set(DTM specifically). What I've tried: Using gdal_contour, I've ...
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Printing geographical centroid coordinates of georeferenced image in CSV file

I am trying to print the centroids of the circular contours from the image. The image is already georeferenced using GDAL with ESRI 102025 and I tried to extract the points in terms of the ...
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163 views

Enclosing contour lines along edges

I have contour lines that I am converting to polygons. Contours along the edge are clipped so are difficult to simply convert to polygons. So I'm trying to find an automated way to do this within QGIS....
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Creating contours based on values of ramp using QGIS

When creating contour on a raster using QGIS, is it possible to create them based on values specified in a colour ramp ? I only see the option "Interval between contour lines".
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Heatmap with Contour Polygons

I have point data off the coast of Oahu. Someone else used these same data to create two polygons (approximated by me in the figure below with the green and red hand-drawn boundary lines). I believe ...
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Contours not saved [closed]

I have generated several bathymetry layers using the contour plugin. These are saved in memory. I have installed the memorylayer saver plugin which recognises the layers concerned. When I try to make ...
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Contour Lines exported as raster in Illustrator

I am trying to export contour lines from arcgis to illustrator to finish the map. I have tried to export the map with "vectorize layers with bitmap markers/fills" option, but it still opens ...
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Making polygons from interpolated points in QGIS

I need to know the extension of the area of a lagoon according to depth classes. I started from a point shapefile containing depth values and used the interpolation plugin and I obtained a raster file....
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Grid from SAGA natural neighbor results in black grid

I'm new in QGIS and I'm following tutorials mainly on YouTube so I created a path in Google Earth then exported to kml which is converted to txt via GPS visualizer. When added delimited layer it shows ...
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Extract the mean elevation from a raster by a mask with several spatial objects

I am working with a glacier and I want to get the Hypsometric curve of the elevation difference between two time periods. I divided the mask of the glacier by the contour lines (each 50 m) and now I ...
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Contouring in ArcGIS from raster file yielded rectangular contours

Why does Contouring in ArcGIS using Contour tool in ArcGIS from raster file yielded rectangular contours? The attached image of contour is shown below The contours shows a rectangular gridded ...
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Making Ridge Line and Valley Line from Contours or DEM using SAGA GIS

How do I make ridge lines and valley lines using open source GIS Software? I am totally stuck. I found solution in SAGA GIS - also available in QGIS but it freezes when I run it. http://www.saga-gis....
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1 vote
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Using contours to create polygons around hills in R [closed]

I have a shapefile with contours for a Brazilian state. The contours give me the elevation across that particular state. My goal is to use the contours to identify hills. Ultimately, I would like to ...
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Generate Contour Plugin

I have 6 point .shp files wich contain elevation data, the first 3 files are rather small (about 200MB for the shp and 1GB for the dbf) and the last 3 much larger (500MB .shp and 3.5GB for dbf). I ...
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Fix unwanted sink contours from hydrologically correct DEM

I am creating contours from a DEM that has been hydrologically corrected via a Breach Depressions algorithm. The DEM is coloured light grey to dark grey (top to bottom), the stream is in blue and the ...
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