These functions take signals returned from aggregate_signals() and convert
between formats. covidcast_longer() takes the output of
aggregate_signals(..., format = "wide") and converts it to "long" format,
while covidcast_wider() takes the output of aggregate_signals(..., format = "long") and converts it to "wide" format.
covidcast_longer(x)
covidcast_wider(x)A covidcast_signal_wide or covidcast_signal_long object, as
returned from aggregate_signals() with the respective format argument.
The object pivoted into the opposite form, i.e. as if
aggregate_signals() had been called in the first place with that
format argument.