How to Query KML point data as CSV using QGIS and R

How to Query KML point data as CSV using QGIS and R

Here you can see more than 800 points, each describing an observation of an individual bird. This data is in the form of KML, a sort of XML document from Google for spatial data.

I want to know which points have “pair” or “female” in the description text nodes using R. This way, I can quickly make and update a .csv in Excel of only the paired birds (based on color bands).

Even if there was a description string search function in Google Earth Pro (or other organization-centric GIS/waypoint software), this method is more

robust, as I can work immediately with the output as a data frame in R, rather than a list of results.

First, open an instance of QGIS. I am running ~2.8 on OSX. Add a vector layer of your KML.

“Command-A” in the point dialog to select all before import!

Next, under “Vector”, select “Merge vector layers” via Data Management Tools.

Select CSV and elect to save the file instead of use a temporary/scratch file (this is a common error).

Open your csv in Excel for verification!

The R bit:

_# query for paired birds

#EDIT: Libraries library(data.table) library(tidyverse)_

data <- data.frame(fread(“Bird_CSV.csv”))

pair_rows <- contains(“pair”, vars = data$description)

fem_rows <- contains(“fem”, vars = data$description)

result <- combine(pair_rows, fem_rows)

result <- data[result,]

write_csv(result, “Paired_Birds.csv”)

Tada!

-Jess

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