Questions tagged [contour]

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

Filter by
Sorted by
Tagged with
1 vote
1 answer
20 views

Cannot show ocean bathymetry contour lines in Google Earth Engine

I am new to Google Earth Engine (GEE). Recently I hope to show the ocean bathymetry contour lines by using the ETOPO1 dataset. Here is my code: // Import ETOPO1 bathymetry dataset and choose a band. /...
1 vote
0 answers
28 views

Extending line features to another line features with same attribute value using ArcGIS Pro

I am using ArcGIS Pro. I have received a set of contour lines from a third-party person. After analyzing the polyline data, I have seen a bunch of contour lines having a gap between other contour ...
2 votes
2 answers
87 views

Changing contours from 5 ft to 10 ft in attribute table using QGIS

I downloaded a file of contour lines that has a line every 5 ft of elevation change. This data is extremely dense and makes the map hard to read. Because I don't have the DEM or source data I can't ...
  • 21
0 votes
1 answer
23 views

Select values of noise contours along one road

I have a map of noise contours across a city and am using ArcGIS Pro. I want to select one road (not straight) and export the noise values along that road to a table but I'm having trouble selecting ...
  • 1
1 vote
1 answer
25 views

Offset lines to find self intersection lines

I've been trying, with no success, to create of negative offset from line shapefiles (contour lines, actually). My objective is, with the x offset I define, to use the topology rules to identify the ...
0 votes
1 answer
35 views

Automated digitization within a point layer in QField

I am attempting to create elevation contour lines for a piece of property with the help of a GNSS sensor hooked up to a tablet with QField installed. So far, it looks like the screenshot below. I used ...
1 vote
0 answers
36 views

QGIS: Heatmap of polutant data using contour polygons

1. ASSIGNMENT I have got an even grid of points (figure 1) with attributes of the values of emissions or pollutants caused by traffic - modelled in a specialised SW for this. I need to use this point ...
0 votes
1 answer
20 views

Interpolating between discontinuous contour lines and simple dots

I am trying to find the depths corresponding to purple point locations (given in picture). Depth information is given in contour lines. The main purpose is applying linear interpolation but I don't ...
3 votes
1 answer
99 views

QGIS clear gap visible between contour polygons

When I get rid of the stroke width and style in my contour polygons, I can see very thin one-pixel large gaps between said polygons. How do I get rid of those thin clear lines?
1 vote
0 answers
49 views

Contour Polygons Missing coastline using QGIS

I have a base DEM for which I'm creating some contour polygons. Once I've run the tool, I get the polygons without the landmass' coastline, which I'd like to have, obviously. My workflow (see screen ...
0 votes
0 answers
9 views

How can I create a geologic long section in Geovia GEMS?

I'm trying to create a geological long section to display grade x thickness intersection of drill holes within a particular zone. I have successfully imported the point data but need to figure out how ...
  • 1
4 votes
2 answers
144 views

Extract Single (or small number) Contour from DTM data in QGIS

I understand that Contour data can be extracted at particular intervals fairly easily, but have been recently mapping a number of Flood Water Design levels which are denoted to the nearest 0.001m. It ...
  • 197
0 votes
0 answers
19 views

QGIS - Avoid DEM cells where no vector contours when using TIN

I'm using QGIS TIN functionality to create a DEM (image attached) from vector contours (image attached). I have set the TIN to Attribute Type = 'Break Lines' and the Interpolation Type = 'Linear'. My ...
  • 21
0 votes
0 answers
40 views

Variable resolution across DEM in QGIS

I am try to build a contour map from this DEM but I've noticed that the resolution varies across it resulting in orthogonal contours and 'choke points' where contours are sharply forced together. How ...
  • 1
0 votes
0 answers
19 views

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 ...
0 votes
1 answer
65 views

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?
  • 1
0 votes
0 answers
61 views

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 ...
  • 21
1 vote
1 answer
120 views

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 ...
  • 35
4 votes
2 answers
362 views

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 ...
1 vote
1 answer
80 views

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 ...
  • 13
0 votes
0 answers
92 views

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 ...
  • 137
3 votes
1 answer
118 views

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 ...
0 votes
1 answer
62 views

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 ...
0 votes
0 answers
30 views

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 ...
3 votes
1 answer
25 views

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 ...
  • 141
1 vote
1 answer
124 views

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 ...
0 votes
1 answer
58 views

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?
1 vote
1 answer
113 views

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 ...
  • 129
2 votes
1 answer
49 views

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.
1 vote
0 answers
67 views

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. ...
0 votes
0 answers
106 views

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(...
0 votes
0 answers
44 views

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 ...
  • 9
1 vote
0 answers
139 views

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. ...
  • 355
2 votes
1 answer
287 views

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....
  • 123
2 votes
1 answer
78 views

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 ...
  • 21
0 votes
1 answer
60 views

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 ...
0 votes
1 answer
34 views

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 ...
0 votes
2 answers
46 views

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 ...
2 votes
1 answer
219 views

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/...
  • 61
1 vote
1 answer
47 views

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 ...
  • 81
0 votes
2 answers
79 views

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 ...
0 votes
1 answer
154 views

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 ...
  • 11
0 votes
2 answers
554 views

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 ...
-2 votes
1 answer
47 views

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?
  • 1,605
1 vote
0 answers
50 views

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 ...
  • 1,484
1 vote
1 answer
131 views

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 ...
0 votes
0 answers
192 views

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?
0 votes
0 answers
226 views

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 ...
  • 101
3 votes
1 answer
111 views

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 ...
3 votes
1 answer
230 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....
  • 438

1
2 3 4 5
11