In a previous article we discussed how to create a layer lines from a
file text or Excel with Arcmap . Now is the turn with QGis.There are only two differences
- the first is that it is not necessary to load the Excel table, and then save it in as a layer (shapefile)
- the second is that there is no option to close automatically the lines by linking
the last point to the first point of each line .
The file containing this information is an Excel
table such as :
Regarding the creation of a layer of dots we have to count with an X and
a Y field that will create the corresponding point. In order to get an entities line, we need a third essential
field that includes an identifying line: all points of a line will have the
same value for this field. A fourth field is necessary to indicate the order of
the points. but we will discuss how to create this field when using the
Let’s see the procedure in detail .
To create a layer from a virtual a Excel sheet , you need the Spreadsheet
Layers plugin .
Go to the Extensions menu ->
Install /manageextensions and double-
click on the ” Spreadsheet layers ” extension .
the left vertical toolbar you will notice
a new tool
on this tool .
With the Browse button … point to your Excel file , and , if necessary
, with the drop-down menu select the sheet including your data .
Name the layer .
Check the box Geometry and enter the corresponding field names for X and
Select the SRC (reference system) for your data ( eg EPSG : 4236 if it’s
latitudes / longitudes).
The points layer is displayed in QGis.
In the panel Treatments , go in GeoprocessingQGis ->creationofvectorsTools-> pointstolines
Before launching the tool , check that it, indeed, exist an Id field that gives the order for the
recordings . If this is not the case :
- select the layer you have just loaded
click on the ” Field Calculator ” tool , this opens the corresponding table
- Leave the check box Create new field checked
- Name the field, for example Sorting or Order
- To double-click the expression row_number or on Recordings -> $ id
- Click OK. You will get a field available for the tool Points to lines .
Double-click the processing tool to run.
Fill in the Input Layer fields
and grouping field and sort field.
If you want to create a file on the disk , click on the …
button of Paths and give the file a name at the exit.
Click on RUN .
The final result is displayed in QGis.