Below we provide examples in R, Python and curl showing how to work with our Data Extract API to explore NHGIS metadata.

Get your key from https://account.ipums.org/api_keys. Make sure to replace 'MY_KEY' (all caps) in the snippet below with your key.

Load Libraries and Set Key

• Python
• R
• Curl

import requests
import json
from pprint import pprint

my_key = MY_KEY

# You have to install the httr and jsonlite libraries if they are not already installed.

library(httr)
library(jsonlite)
my_key <- MY_KEY

export KEY=MY_KEY # set the MY_KEY environment variable using bash shell

Now, the usage of the IPUMS NHGIS Metadata API will vary depending on whether you are requesting datasets or time series tables. See the following sections for next steps:

• IPUMS NHGIS Dataset Metadata
• IPUMS NHGIS Time Series Metadata
• IPUMS NHGIS Shapefile Metadata