Questions tagged [terminology]
Indicates questions asking about the use and meaning of specific technical words in GIS.
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"Fighting on the same map" - Who uses this term? [closed]
I have heard the term "Fighting on the same map" a few times, especially when referencing to emergency agencies or military departments. I believe it is mostly used in a way to describe ...
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1
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How was the term 'Feature' originally defined in GIS? [closed]
Esri defines Feature as a cartographic term:
[cartography] Any part of the earth's surface, or anything found on the earth's surface, that can be represented on a map. Features can represent various ...
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What is name/terminology for area in .tif satellite image file which is blank space/not land?
I have some L2 satellite images from an MSI bundle, and I need to produce a mask over the area in the file which is not the image itself - the black part in the image below.
What is the technical name ...
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What is origin of term "network" in Network Common Data Form (NetCDF) format specification
I see (on Wikipedia) that the NetCDF format evolved from a specification for storing multidimensional data called the "Common Data Format".
Semantically... the word "network" has a ...
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Computing visual "center" of irregular polygon
UPDATE: centroid is fine, my initial implementation was not weighing the edge length. With that fix all is well.
I am using the centroid to render a marker in the "center" of a parcel, but ...
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What do you call two isochrone maps that shows the intersection between two points as a "meeting" line?
I've learned today what isochrone maps are but now I sort of want to combine two isochrone so that a line forms right where the maps meet in the middle time wise.
As in, if each point travels the same ...
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Difference between control point, reference point, and tie point
I georeferenced a map using grid coordinate and road network shapefile (e.g. intersection vertex) as a control point. I didn't acquire a control point through the survey.
I use "control point (...
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Is there an equivalent term to 'imagery' in context with maps and cartography?
Is there an equivalent term to imagery in context with maps or cartography?
Mappery seems not to exist. (I'm from Germany, and some miles away from being a native-English speaker)
To explain that a ...
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What does context mean in PyQGIS?
When writing PyQGIS scripts, especially processing script and expression function, I come across the term context. I use it, but I don't know what all contexts mean actually.
There are also Qgs***...
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Difference between Image layer and Tile Layer
what is the basic difference between Image Layer and Tile Layer? Apart from the documentation....which says below points
ol/layer/Tile - Renders sources that provide tiled images in grids that are ...
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Difference and similarities between Intervisibility and Viewshed [closed]
I am just looking for what the difference and similarities for Intervisibility and Viewshed.
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397
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How do "layer", "feature", "attribute", "field", and "data provider" relate?
I'm new to QGIS, but familiar with Python and PyQt, and am trying to make sense of the terminology of "layer", "feature", "attribute", "field", and "data ...
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242
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Naming convention for ways of defining direction
The following two conventions for defining direction are very common, but what are they called?
0 at north, clockwise
0 at positive x-axis, counterclockwise
Background: I'm writing a function that ...
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Correct terminology to describe regular grid
What is the correct terminology to describe a regular grid of squares based on certain distance in latitude/longitude? I came up with this description:
We used regular grid of squares measuring 10' ...
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What is the difference between Ground Sampling Distance (GSD) and spatial resolution?
In research papers on remote sensing, I see some authors referring to spatial resolution (expressed as pixel/distance) and others to Ground Sampling Distance (GSD) (also expressed as pixel/distance). ...
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Do I necessarily need coordinates for spatial prediction?
Commonly, it is stated that spatial prediction is the same as spatial interpolation, i.e. the estimation of values based on the observations' location:
y ~ lon + lat
Others state, that spatial ...
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Does the concept of a map service exist in ArcGIS Online?
I'm new to web GIS.
I have created an ArcGIS Online account that contains:
Web Maps
Feature Layers (hosted)
It is my guess that the term feature layer is a synonym for feature service.
If that's ...
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Is climate a small-scale or large-scale process? [closed]
This might sound like a stupid question but it bothers me anyway:
We distinguish small-scale maps like world-maps and large-scale maps like a map of my local neighborhood. So far, so clear.
However, ...
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What is the term for creating a network from scratch?
As part of my PhD, I developed a simple way of creating a road network splitting up collected coordinates based on where they cross. I know the standard method is to use a shapefile (or similar) as ...
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Meaning of 'bnds' and dimensions in OCO2 v9 L3 data product
I cannot seem to understand what, for example, 'lat_bnds' means? Same go for 'lon_bnds', lat/lon_dimensions. These values come from the structurally flat NCDF4, sourced from the JPL as a custom ...
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What is getting nearest points between two different but nearby (almost intersecting) datasets called?
I need some terminology help as I am still learning GIS. This is related to, but not the same as, What is getting nearest points between two different but overlaping datasets called?
I have two ...
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What is getting nearest points between two different but overlaping datasets called?
I need some terminology help as I am still learning GIS.
I have two datasets. One with the address of every fire and it's latitude/longitude of small census tract. One with the location of every ...
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Is there an easy way to say -3.4028234663852886e+38?
A lot of our datasets have a nodata value that is, or close to, -3.4028234663852886e+38.
Can anyone think of an easy way to say this out loud when we're discussing things?
Even "minus three times ...
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What is Time of Validity in a GPS System?
What is time of validity in a GPS system? For defining time of validity, there are only a limited definitions available. My interpretation for time of validity is the built-in system time (like on ...
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What do you call this combination of two district maps?
My real-world problem is that I want to combine state House and Senate legislative districts so that a user can pick a region (not a point) on a map that is included in both their House and Senate ...
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What is difference between BLOB and tile in GeoPackage?
I'm new to GeoPackage, but wrote some code that will read an image file into a buffer and I then insert that buffer into the GeoPackage as a BLOB.
The image files are GeoTIFFs which contain latitude, ...
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What is the proper name for the "Venn diagram" of a set of geometries?
Sometimes, you have a set of overlapping geometries, and you want to generate an output like this:
Image taken from this answer.
The resulting polygons have no overlaps; each region of space is ...
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Interpreting cell coordinates from DEM?
I'm using Environment Agency DTM LiDAR data which I import into Mathematica in ASCII format to produce ground surface models, sections, etc.
The process works fine, but I'm unclear whether the cell ...
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What does percentile mean in simpleComposite of Google Earth Engine?
I was using 'ee.Algorithms.Landsat.simpleComposite' to composite images, but I'm not sure what does this 'percentile' parameter mean?
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In ArcGIS can a feature set use multiple coordinate systems?
I'm new to learning GIS and ArcMap, but have some confusion about coordinate systems. I thought I understood that there are two main types of coordinate systems, Projected Coordinate Systems which ...
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What part of the Census Block is the County?
I have a list of census blocks for California and I am trying to get the county for each row.
If I have a census block of 60070004024003, which 2 digits make up the county FIPS?
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Adjective meaning "of the same resolution and extent"
Is there a word that can be used to describe two or more raster grids having the same resolution and extent? I'm fishing around with words like "coincident" and "coextensive," but nothing feels quite ...
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What does LW stand for in liblwgeom of PostGIS?
What does LW stand for in liblwgeom of PostGIS?
I could not find any explanation anywhere, or in the source code (mirrored) at https://github.com/postgis/postgis/tree/svn-trunk/liblwgeom
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What does the ST prefix stand for, e.g. in ST_Polygonize?
I was just curious, and couldn't find any reference to this anywhere - is it Spatial Types? Spatial Topography? Something else?
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What does M-value represent?
I am trying to wrap my ahead around the meaning of the M-value.
I read ESRI's dictionary definition here: https://support.esri.com/en/other-resources/gis-dictionary/term/m-value
and was not able to ...
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What is the difference between ArcGIS Desktop and ArcGIS FOR Desktop?
I keep seeing these two categories of software package on the ESRI site but nothing making it clear the difference between what ArcGIS Desktop is vs. ArcGIS For Desktop. I use ArcGIS Desktop (i think)...
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How to name this sort of edge?
I'm searching for a certain pathfinding algorithm which considers a certain sort of branch in the network. However, I find it difficult to define my search term as I do not know how this certain kind ...
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Agreed Upon Name for Rows in an Attribute Table
Is there an agreed upon name for the rows in an attribute table, perhaps one that would apply across different GIS software platforms?
Esri uses "records" here, for example. They also have the ...
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What is the difference between Key-Point, Tie-Point in Photogrammetry?
I'm looking into the reports & the Mechanism of UAV Photogrammetry software like Pix4D and AgiSoft.
These two words are mentioned in a lot of support documentation, but they are defined no-where.
...
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Difference between files of extension .asc, .asc.aux.xml, .aux and .rrd?
I have received ASCII data from a client. These ASCII files have been created from LiDAR data.
For each tile there are 4 different file types:
Filename.asc
Filename.asc.aux.xml
Filename.aux
...
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The term for determining the pixels of a raster image
I am looking for an english well-established term for determining:
1) invalid/nodata raster image pixels (№ 1 - black ones on the image below) and
2) valid/data raster image pixels (№ 2 - other ones ...
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Terminology for "projection" on different 2d planes (no sphere involved)
I'm building software and want to use good terminology for variables, tables, etc.
Most of my work involves blueprint drawings on which I render shapes (pins, polygons, etc). The same set of pins can ...
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What does "faceting" mean in a geo/map context?
I saw some folks talking about "faceting" in relation to a map data display, what does this mean in general terms? Examples?
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model builder expressions code block and definitions
I am having difficulty wrapping my brain around the point of the expression vs the code block. What am I suppose to be defining? I copied the example from calculate value in the ArcGIS help website ...
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In which coordinates (x, y, z) are vertical grids expressed?
When working with 2D maps, coordinates are always expressed in X and Y. Adding a 3rd dimension also adds the Z-coordinate, which typically stands for height.
However, when working with vertical ...
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Which projection conserves lengths?
I would like to crop rectangular fragments of given size and for these purposes I need coordinates, which covers all Earth and measured in meters.
I wrote the following picture:
Latitude and ...
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Difference between bounding box, envelope, extent, bounds?
Every time when I create a script to manipulate vector (point, line and polygon) in python I meet this doubt.
What is the difference between bounding box (bbox), envelope, extent, bounds?
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What does "correctly noded" mean?
I've never seen this term, and I'm wondering what it means, with regard to ST_Polygonize
NOTE: Input linework must be correctly noded for this function to work properly
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What's the difference between classification/clustering and zoning?
A week ago I had an exam and there was a question:
What are the main steps of zoning in a GIS?
I didn't understand the question and asked the instructor what does she mean by zoning (in ...
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Finding Similar Map Paths
I'm looking for an algorithm which, when given a particular route on a map with attributes such as incline/distance/shape/etc, can find a route which is similar (in terms of the attributes) but starts ...
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