Reference

Fetch data Fetch signals and metadata from the COVIDcast API
covidcast_signal()	Obtain a data frame for one COVIDcast signal
covidcast_signals()	Obtain multiple COVIDcast signals at once
covidcast_meta()	Obtain COVIDcast metadata
Plot and summarize data Plot and summarize COVIDcast signals and metadata
plot(<covidcast_signal>)	Plot covidcast_signal object as choropleths, bubbles, or time series
print(<covidcast_signal>)	Print covidcast_signal object
print(<covidcast_meta>)	Print covidcast_meta object
summary(<covidcast_signal>)	Summarize covidcast_signal object
summary(<covidcast_meta>)	Summarize covidcast_meta object
Wrangle and correlate signals Calculate correlations, aggregate multiple signals, and move between aggregated data formats
covidcast_cor()	Compute correlations between two covidcast_signal data frames
latest_issue() earliest_issue()	Fetch the latest or earliest issue for each observation
aggregate_signals()	Aggregate covidcast_signal objects into one data frame
covidcast_longer() covidcast_wider()	Pivot aggregated signals between "wide" and "long" formats
as.covidcast_signal()	Convert data from an external source into a form compatible with covidcast_signal.
Geographic utilities Manipulate geographic IDs like FIPS codes and CBSAs
state_fips_to_name() county_fips_to_name() cbsa_to_name()	Get state, county or metropolitan area names from FIPS or CBSA codes
name_to_fips() name_to_cbsa()	Get FIPS or CBSA codes from county or metropolitan area names
abbr_to_fips()	Get FIPS codes from state abbreviations
abbr_to_name()	Get state names from state abbreviations
fips_to_abbr()	Get state abbreviations from FIPS codes
name_to_abbr()	Get state abbreviations from state names
Geographic data Get Census reference and geographic data
county_census	County census population data
msa_census	Metro area population data
state_census	State population data