aqs_qa_blanks_by_MA

Returns a table of blank quality assurance data. Blanks are unexposed sample collection devices (e.g., filters) that are transported with the exposed sample devices to assess if contamination is occurring during the transport or handling of the samples. Data is aggregated by monitoring agency code (MA_code).

Usage

aqs_qa_blanks_by_MA(parameter, bdate, edate, MA_code, return_header = FALSE)

Arguments

parameter

a character list or a single character string which represents the parameter code of the air pollutant related to the data being requested.

bdate

a R date object which represents the begin date of the data selection. Only data on or after this date will be returned.

edate

a R date object which represents the end date of the data selection. Only data on or before this date will be returned.

MA_code

a R character object which represents the 4 digit AQS Monitoring Agency code (with leading zeroes). Use aqs_mas() for a list of all Monitoring Agency (MA) codes and names available,

return_header

If FALSE (default) only returns data requested. If TRUE returns a AQSAPI_v2 object which is a two item list that contains header information returned from the API server, mostly used for debugging purposes in addition to the data requested.

Value

a tibble or an AQS_Data_Mart_APIv2 S3 object that contains quality assurance blank sample data for all monitors within the input MA_code. An AQS_Data_Mart_APIv2 is a 2 item named list in which the first item ($Header) is a tibble of header information from the AQS API and the second item ($Data) is a tibble of the data returned.

Note

The AQS API only allows for a single year of qa_blank data to be retrieved at a time. This function conveniently extracts date information from the bdate and edate parameters then makes repeated calls to the AQSAPI retrieving a maximum of one calendar year of data at a time. Each calendar year of data requires a separate API call so multiple years of data will require multiple API calls. As the number of years of data being requested increases so does the length of time that it will take to retrieve results. There is also a 5 second wait time inserted between successive API calls to prevent overloading the API server. This operation has a linear run time of $mathcal(n + 5 seconds)$.

See also

Other Aggregate _by_MA functions: aqs_qa_annualperformanceeval_by_MA(), aqs_qa_annualperformanceevaltransaction_by_MA(), aqs_qa_collocated_assessments_by_MA(), aqs_qa_flowrateaudit_by_MA(), aqs_qa_flowrateverification_by_MA(), aqs_qa_one_point_qc_by_MA(), aqs_qa_pep_audit_by_MA()

Examples

# Returns a tibble containing PM2.5 blank data in
          #  January 2018 where the Monitoring Agency is the Alabama
          #  Department of Environmental Management (agency 0013)
          if (FALSE) aqs_qa_blanks_by_MA(parameter = '88101',
                                       bdate = as.Date('20170101',
                                                       format = '%Y%m%d'),
                                       edate = as.Date('20190131',
                                                       format = '%Y%m%d'),
                                       MA_code = '0013'
                                       )
                    # \dontrun{}