Get the number of rows per sensor in a mpathsenser database

Usage

get_nrows(
  db,
  sensor = NULL,
  participant_id = NULL,
  start_date = NULL,
  end_date = NULL
)

Arguments

db: db A database connection, as created by create_db().
sensor: A character vector of one or multiple vectors. Use sensor = NULL for all sensors. See sensors for a list of all available sensors.
participant_id: A character string identifying a single participant. Use get_participants() to retrieve all participants from the database. Leave empty to get data for all participants.
start_date: Optional search window specifying date where to begin search. Must be convertible to date using base::as.Date(). Use first_date() to find the date of the first entry for a participant.
end_date: Optional search window specifying date where to end search. Must be convertible to date using base::as.Date(). Use last_date() to find the date of the last entry for a participant.

Value

A named vector containing the number of rows for each sensor.

Examples

if (FALSE) { # \dontrun{
# Open a database connection
db <- open_db("path/to/db")

# Get the number of rows for all sensors
get_nrows(db, sensor = NULL)

# Get the number of rows for the Accelerometer and Gyroscope sensors
get_nrows(db, c("Accelerometer", "Gyroscope"))

# Remember to close the connection
close_db(db)
} # }