# Questions tagged [length]

The longest extent of anything as measured from end to end

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16k views

### Getting geometry length in meters?

In PostGIS, the ST_length() function returns the length of a linestring in some units, but not in meters. Is there a function like ST_Length() but in meters?
4k views

### Looking for a pythonic way to calculate the length of a WKT linestring

I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
16k views

### Understanding terms in Length of Degree formula?

Online calculators such as http://www.csgnetwork.com/degreelenllavcalc.html (view page source) use the below formulas to get meters per degree. I understand in general how distance per degree varies ...
3k views

### POSTGIS get the max length of the polygon and the average width

I have in postgis a polygon type table. I need to calculate automatically the maximum length of the polygon: And the second one is the average width: I am doubting rigth now if this is possible as ...
13k views

### What is unit of shapely length attribute?

I'm doing a very simple calculation of the length of a polyline using shapely: from shapely.geometry import LineString ... xy_list = [map(float,e) for e in xy_intm] line = LineString(xy_list) s = '%...
210 views

### Calculating polygon's length along a line?

I need to calculate the length of polygons along / projected on a line. An image to show the idea: I have thousands of polygons to be "projected" on lines to verify how many meters of the line they ...
715 views

### Deciding length of shapefile fields?

At my work have inherited several shapefiles that originate from MapInfo that I am bringing into a new project in QGIS. I have the opportunity to change the column names, add and subtract columns and ...
15k views

### What units are shape_length in?

When generating polylines from a series of points, I used "Points to Line" tool. From this, Arc generates a polyline feature class, which includes the attribute shape_length. What units are these ...
3k views

### Calculating the length of the network lines inside polygon in QGIS 2.10.1

I am working with 2 datasets: delineations of the neighbourhoods traffic network. This is how they look: I would like to calculate the length of the roads per neighbourhood (polygon). As you may ...
13k views

### Calculating line segment lengths within polygon using ArcGIS Desktop?

I have a layer with line segments and a layer of polygons (in this case, buffers around points). I need to create a new field for each polygon that contains the total length of all line segments ...
8k views

### Finding line length while editing in QGIS?

I am using QGIS. I would like to know if there is any way during the editing phase of a vector (line or polygon) to know the length of the line (total and partial) that is being created?
480 views

### Length of line differs depending on query method

We are doing a check of a length attribute against the Shape Length in all our line feature classes (maybe 40 feature classes and 200,000+ features). In the length attribute we round the Shape Length ...
3k views

### How to measure length of line accurately?

In postgis 1.5 for the below given query the answer is 1540651.62674101 meters , SELECT ST_Length(ST_GeomFromText('LINESTRING(77.83042478941326 9.98463896136159,78.03469506809812 23.90398909552571 )'...
1k views

### How to create line with exact same length over and over again?

I need to draw 30 meter lines in specific places. Ctrl+l is too annoying to do everytime. Is there a easy way to define specific same length for a line that I need to draw many times?
2k views

### What's the unit of measurements produced by “sum line lengths”?

My goal is to find the total length of roads per county for a particular state. You would think there would be a simple government spreadsheet with this information in it.... I cannot figure out how ...
1k views

### How to emulate a specific vector grid in QGIS?

I would like to analyze data included in a pdf file. The file contains information on characteristics of 16km grid cells for a specific study area. The file also includes a map displaying the grid. I ...
527 views

### Permanently setting polygon/polyline segment length using ArcGIS Desktop?

I'm trying to create a several hundred polygons in ArcGIS 10, each of which may have up to several hundred vertices. For consistency sake I would like each line segment in these polygons to be of a ...
7k views

### How to create a rectangle polygon with set lengths in QGIS?

I have a search area i want to outline. and i need it to be 1km by 2km. is it possible to achieve this in QGIS. I can create a rectangle polygon but only guess the lengths.
115 views

### Different length measures in QGIS vs. ArcMap

I noticed that QGIS and ArcMap return slightly different length measures when calculating geometries (length) on one and the same shapefile (see image). In QGIS I used the \$length command, in ArcMap ...
2k views

### Why is sum of st_length() of segments 20% too big?

I'm running a query to return the total length of some bike paths, from OpenStreetMap. Compared to the known actual length of these paths, they're all a bit too big - something like 10-30%. I know it ...
234 views

### Measurement not correct in QGIS 1.8 [closed]

I have a SHP file of sub-areas of U.S. counties (roughly about the size of a Census tract) that I've reprojected into a 'true distance' projection (World Equidistant Cylindrical) in QGIS 1.8. However, ...
330 views

### How is the st_length function stored in an Oracle geodatabase?

How is the st_length function stored in an Oracle geodatabase? Is it in a: PL/SQL function Separate .dll library Somewhere else? I've noticed that the sde.st_length function works, even when the ...
347 views

### OGR2OGR how to update a new column by the length of polyline

Hi I can update new column with area of a polygon object, but don't know, how to update new column in polyline layer with length of polyline. This works very well for AREA: for %%f in (*.tab) do ( ...
2k views

### Using Calculate Field (Data Management) tool to calculate 3D Length in ArcGIS 10.1

I'm relatively new to the world of model builder and scripting, so it's likely there is a very simple solution to the question I've been trying to figure out. I'm trying to create a tool that takes ...
67 views

### Incorrect measurement of intersection between polygons

I have a map divided in parts using polygons, and I want to measure the length of the boundary between each pair. I am using this script from a tutorial to find the actual neighbors, and then measure ...
271 views

### QGIS: Displaying total length of lines in print composer legend

In the print composer (also in the layer selector) I can choose to automatically display the amount of objects in that category in square brackets. That is useful for point features/layers. But in the ...
75 views

### Loop distance point PyQGIS

I have a .shp of lines where I'm able to calculate the sum of segments length but I'm trying to put a point at a given distance in meters. The problem is it puts a point at every segment. When I give ...
395 views

### Calculate length of huge vector lines dataset

I have a MultiLineString vector layer from which I would like to calculate the length. I have tried to calculate the length with the Field Calculator by putting in the expression \$length. The ...
15k views

### Polyline length calculation in ArcGIS 10/VB script

I used to run this length calc on my data in ArcGIS 8 and 9, and now it don't work in ArcGIS10. Can you tell me what I have done wrong? Dim dbllength as double Dim pcurve as icurve Set Pcurve = [...
1k views

### How to measure the length/area of a line/polygon by just selecting it?

I can get what I want by using this code but have to do it everytime i select. The geometry of the features are small (city scale). layer = qgis.utils.iface.activeLayer() features = layer....
718 views

### How to calculate path length of each point from the start using arcpy?

As shown in the picture below I would like to calculate the path length of each point from the start. Can anyone give me some help in writing this in python for ArcGIS?
3k views

### Get LineString length in meters (Python, GEODjango)

In a Django model, I have a LineString field which holds GPS coordinates of a street route. I know that I the .length holds the length of the LineString, but I don't know what unit the returned value ...
3k views

### How to Calculate length of polyline geometry for several tables in PostGIS?

PostGIS database contains several geometry (polyline) tables (with names "D1_r", "D2_r", "D3_r"). I calculate length for one "postgis layer" use request: SELECT sum(ST_Length_Spheroid(the_geom,'...
1k views

### ArcGIS Surface Length Tool equivalent in FME?

I am trying to calculate the 3D length of a line. I currently have a rather complex and cumbersome model built in ArcGIS ModelBuilder that uses a tool called "Surface Length". I was wondering if ...
761 views

### Measure length of each segment for a polygon in Postgis

I have a polygon table in PostGIS and need to calculate the length of each line segment. How can I achieve this? I have done it in QGIS but would prefer to do it in the database. I have found ...
188 views

### Different results using \$length (field calculator) in QGIS versions 2.18 and 3.0

I use the field calculator to measure the length of LineStrings in my shapefile layer, but i get different results when using QGIS 2.18 or QGIS 3.0. If I am using the local coordinate system the ...
674 views

### Measuring polyline lengths running through a raster - is this possible?

I have a reclassified raster layer with 4 values and a vector layer of polylines. I would like to discover the length of the lines running through each raster value, or the percentage of the lines ...
171 views

### Get 3D length of line from contours (as attribute)

I have a road feature class (not currently Z enabled), and a contour feature class (which has elevations as an attribute). How can I generate the 3d length of roads as an attribute? Environment: ...
2k views

### Problem about converting raster to polyline and calculating total length

I have raster file of line segment. I need to convert it to line and get the distance of that line. How can i do using Python and ArcGIS 10? I have tried with GIS tools Convert Raster to Polyline but ...
2k views

### How to get turn angle, line orientation and line length in ArcMap 9.3.1?

I am mapping and analysing animal movements using arcgis 9.3.1 along with Hawthorne Beyer's GME, and am trying to utilise the correlated random walk commands, but in order to do this I need to find ...
2k views

### How to convert length in Decimal degrees to meters programmatically?

I'm new to qgis and I want to find the length of some roads in a map. So I used the following code, from shapely.wkb import loads def getLength(): layer = qgis.utils.iface.mapCanvas().currentLayer()...
375 views

### Sum line length with clip intersect? [closed]

SELECT sum(st_length(st_intersection(POLY.geom, LINE.geom))) AS sum_line_length... Is this function OK to calculate the sum of lines length? Wonder if it do the clip line where one line go from one ...
53 views

### Lines length plugin - QgsVectorLayer error

Several similar questions have already been made, but none of the is helping me. I have a layer of polygons and I want to known the length of each line of each polygon. And based on the length I ...
79 views

### QGIS - Parallel Lines - Count length of one

I have a large layer of lines (telecommunication duct) with in parts several parallel lines that are close to each other (cause they lay in the same trench). I would like to count the length of the ...
292 views

### Wrong length values on QGIS 3.0.3 and 3.2

While using QGIS 3.x today I noticed that length values were not calculated and measured correctly on EPSG:32611. Calculating and measuring the same data on QGIS 2.18 latest LTR and 2.2 on EPSG:32611 ...
157 views

### How to measure orthogonal distance of line from point in QGIS?

As I am fairly new to QGIS I'm seeking your help. I'm trying to measure the distance between points in a point Layer P and the end of lines in a line layer L. In L there are two categories (attributes)...
1k views

### FME - calculating distance to points along a line

I am new to FME, and trying to get my head around what should be pretty straightforward issues, but I find myself going around in circles Basically I want to determine the distance (chainage) to a ...
6k views

### Calculating sum of geometric length of shapefile in ArcGIS Desktop?

I have a shapefile with lots of line routes. I projected it and calculated the length using calculate geometry. How can I get the sum of all these routes in ArcGIS Desktop?