--- title: "Getting Started with laOpenData" output: rmarkdown::html_vignette author: "Christian Martinez" vignette: > %\VignetteIndexEntry{Getting Started with laOpenData} %\VignetteEngine{knitr::rmarkdown} %\VignetteEncoding{UTF-8} --- ```{r, include = FALSE} knitr::opts_chunk$set( collapse = TRUE, comment = "#>" ) ``` ```{r setup} knitr::opts_chunk$set(warning = FALSE, message = FALSE) library(laOpenData) library(ggplot2) library(dplyr) ``` ## Introduction Welcome to the `laOpenData` package, an R package dedicated to helping R users connect to the [Los Angeles Open Data Portal](https://data.lacity.org/)! The `laOpenData` package provides a streamlined interface for accessing Los Angeles' vast open data resources. It connects directly to official City of Los Angeles open data portals, including datasets hosted across Socrata-powered city domains, helping users bridge the gap between raw city APIs and tidy data analysis. This package is part of a broader ecosystem of open data tools designed to provide a consistent interface across cities. It does this in two ways: ### The `la_pull_dataset()` function The primary way to pull data in this package is the `la_pull_dataset()` function, which works in tandem with `la_list_datasets()`. You do not need to know anything about API keys or authentication. The first step would be to call the `la_list_datasets()` to see what datasets are in the list and available to use in the `la_pull_dataset()` function. This provides information for thousands of datasets found on the portal. ```{r la-list-datasets} la_list_datasets() |> head() ``` The output includes columns such as the dataset title, description, and link to the source. The most important fields are the dataset `key` and `id`. You need **either** in order to use the `la_pull_dataset()` function. You can put **either** the key value or id value into the `dataset =` filter inside of `la_pull_dataset()`. For instance, if we want to pull the dataset `Building and Safety - Vacant Building Abatement`, we can use either of the methods below: ```{r la-vacant-pull} la_building_safety_vacant <- la_pull_dataset( dataset = "q3ak-s5hy", limit = 2, timeout_sec = 90) la_building_safety_vacant <- la_pull_dataset( dataset = "building_and_safety_vacant_building_abatement", limit = 2, timeout_sec = 90) ``` No matter if we put the `id` or the `key` as the value for `dataset =`, we successfully get the data! ### The `la_any_dataset()` function The easiest workflow is to use `la_list_datasets()` together with `la_pull_dataset()`. In the event that you have a particular dataset you want to use in R that is not in the list, you can use the `la_any_dataset()`. The only requirement is the dataset’s API endpoint (a URL provided by the Los Angeles Open Data portal). Here are the steps to get it: 1. On the Los Angeles Open Data Portal, go to the dataset you want to work with. 2. Click on "Export" (next to the actions button on the right hand side). 3. Click on "API Endpoint". 4. Click on "SODA2" for "Version". 5. Copy the API Endpoint. Below is an example of how to use the `la_any_dataset()` once the API endpoint has been discovered, that will pull the same data as the `la_pull_dataset()` example: ```{text} la_motor_vehicle_collisions_data <- la_any_dataset(json_link = "https://data.lacity.org/resource/q3ak-s5hy.json", limit = 2) ``` ### Rule of Thumb While both functions provide access to Los Angeles Open Data, they serve slightly different purposes. In general: - Use `la_pull_dataset()` when the dataset is available in `la_list_datasets()` - Use `la_any_dataset()` when working with datasets outside the catalog Together, these functions allow users to either quickly access the datasets or flexibly query any dataset available on the Los Angeles Open Data portal. ## Real World Example Los Angeles has a lot of people, and just as many businesses, and the list of active businesses in LA is contained in the dataset, [found here](https://data.lacity.org/Administration-Finance/Listing-of-Active-Businesses/6rrh-rzua/about_data). In R, the `laOpenData` package can be used to pull this data directly. By using the `la_pull_dataset()` function, we can gather information on these businesses, and filter based upon any of the columns inside the dataset. Let's take an example of 3 requests that occur in the actual city of Los Angeles. The `la_pull_dataset()` function can filter based off any of the columns in the dataset. To filter, we add `filters = list()` and put whatever filters we would like inside. From our `colnames` call before, we know that there is a column called "city" which we can use to accomplish this. ```{r filter-location} la_businesses <- la_pull_dataset(dataset = "6rrh-rzua",limit = 3, timeout_sec = 90, filters = list(city = "LOS ANGELES")) la_businesses # Checking to see the filtering worked la_businesses |> distinct(city) ``` Success! From calling the `la_businesses` dataset we see there are only 3 rows of data, and from the `distinct()` call we see the only location featured in our dataset is LOS ANGELES. One of the strongest qualities this function has is its ability to filter based off of multiple columns. Let's put everything together and get a dataset of *50* businesses that occur in LOS ANGELES in council district 8. ```{r filter-la-eight} # Creating the dataset la_businesses_8 <- la_pull_dataset(dataset = "6rrh-rzua", limit = 50, timeout_sec = 90, filters = list(city = "LOS ANGELES", council_district = 8)) # Calling head of our new dataset la_businesses_8 |> slice_head(n = 6) # Quick check to make sure our filtering worked la_businesses_8 |> summarize(rows = n()) la_businesses_8 |> distinct(city) la_businesses_8 |> distinct(council_district) ``` We successfully created our dataset that contains 50 requests regarding the businesses in district 8 of LA. ### Mini analysis Now that we have successfully pulled the data and have it in R, let's do a mini analysis on using the `primary_naics_description` column, to figure out what are the main types of businesses To do this, we will create a bar graph of the business types. ```{r complaint-type-graph, fig.alt="Bar chart showing the frequency of business types in LA in district 8.", fig.cap="Bar chart showing the frequency of business types in LA in district 8.", fig.height=5, fig.width=7} # Visualizing the distribution, ordered by frequency la_businesses_8 |> count(primary_naics_description) |> ggplot(aes( x = n, y = reorder(primary_naics_description, n) )) + geom_col(fill = "steelblue") + theme_minimal() + labs( title = "Top 50 Business Types in District 8 of LA", x = "Number of Businesses", y = "Business Type" ) ``` This graph shows us not only *which* businesses are in the area, but *how many* of each there are. ## Summary The `laOpenData` package serves as a robust interface for the Los Angeles Open Data portal, streamlining the path from raw city APIs to actionable insights. By abstracting the complexities of data acquisition—such as pagination, type-casting, and complex filtering—it allows users to focus on analysis rather than data engineering. As demonstrated in this vignette, the package provides a seamless workflow for targeted data retrieval, automated filtering, and rapid visualization. ## How to Cite If you use this package for research or educational purposes, please cite it as follows: Martinez C (2026). laOpenData: Convenient Access to Los Angeles Open Data API Endpoints. R package version 0.1.0, .