A Connecting to NAPMD
NAPMD can be accessed via:
- an API (requiring an API username and password), or
- Postgres connection (requiring a database username and password).
The instructions that follow are aimed primarily at R users. To use R, you will need to install both R and RStudio.
A.1 Using API with R napmdtools package
R functions that interface with the NAPMD API can be found in the napmdtools package. See the package repository and instructions here.
A.2 Via DB connection with R RPostgreSQL package
Connect to the database with the following:
# Load RPostgreSQL library
require("RPostgreSQL")
# Load the PostgreSQL driver
drv <- dbDriver("PostgreSQL")
## create your password
## Either (NOTE: this window can open in the background, so you might need to minimise RStudio to see it.
postgres_pwd <- askpass::askpass(prompt = "Please enter your password: ")
## OR
# postgres_pwd <- "<your_password>"
## Create a connection to the postgres database
ch <- dbConnect(drv, dbname = "postgis_car",
host = "<server_name>", port = 5432,
user = "<user_name>", password = postgres_pwd)
remove(postgres_pwd)Once connect, use the dbGetQuery function to query with the database using SQL. For example:
df.mons <- dbGetQuery(ch, "SELECT * from air_pollution_monitors.ap_monitor_data_master
where state = 'SA'
limit 100;")For geospatial work, you can read the locations tables directly into an sf or SpatVector (terra) object through the rpostgis package:
library(rpostgis)
# read as sf object
sf.mons <- rpostgis::pgGetGeom(ch,
c("air_pollution_monitors", "ap_monitor_locations_act"),
geom = "geom_gda94",
returnclass = "sf")
# or as terra SpatVector
v.mons <- rpostgis::pgGetGeom(ch,
c("air_pollution_monitors", "ap_monitor_locations_act"),
geom = "geom_gda94",
returnclass = "terra")A.3 Via pgAdmin 4
- Download and install PGAdmin 4 https://www.pgadmin.org/download/
- Run PGAdmin 4
- In the left sidebar, right-click on
Servers->Create->Server... - Name the Server in the General Tab
- In the Connections tab fill in the following details, replacing
, and with the credentials given to you. Then save the changes.
You may then navigate using the tree in the left sidebar. Find the air_pollution_monitors schema in the Schemas list.
To run SQL queries, open the Query Tool (Tools > Query Tool in the top menu, or right-click a schema or table and click Query Tool). Run your query with the Execute/Refresh button (shortcut key F5) above the top-right pane. Save query results with the Save results to file button (shortcut key F8).