eplusr (version 0.9.4)

EplusSql: Retrieve Simulation Outputs Using EnergyPlus SQLite Output File

Description

EplusSql class wraps SQL queries that can retrieve simulation outputs using EnergyPlus SQLite output file.

Usage

epsql <- eplus_sql(sql)
epsql$path()
epsql$list_table()
epsql$read_table(table)
epsql$report_data(key_value = NULL, name = NULL, year = NULL, tz = "GMT", case = "auto", all = FALSE)
epsql$report_data_dict()
epsql$tabular_data()
epsql$print()
print(epsql)

$path() returns the path of EnergyPlus SQLite file.

$report_data_dict() returns a data.table which contains all information about report data. For details on the meaning of each columns, please see "2.20.2.1 ReportDataDictionary Table" in EnergyPlus "Output Details and Examples" documentation.

$report_data() extracts the report data in a data.table using key values and variable names.

$tabular_data() extracts all tabular data in a data.table.

$print() shows the core information of this EplusSql object, including the path of the EnergyPlus SQLite file, last modified time of the SQLite file and the path of the IDF file with the same name in the same folder.

Arguments:

• epsql: An EplusSQL object.

• sql: A path to an local EnergyPlus SQLite output file.

• key_value: A character vector to identify key name of the data. If NULL, all keys of that variable will be returned. Default: NULL.

• name: A character vector to specify the actual data name. If NULL, all variables will be returned. Default: NULL.

• year: The year of the date and time in column DateTime. If NULL, it will be the current year. Default: NULL

• tz: Time zone of date and time in column DateTime. Default: "GMT".

• case: If not NULL, a character column will be added indicates the case of this simulation. If "auto", the name of the SQL file will be used.

Details

SQLite output is an optional output format for EnergyPlus. It will be created if there is an object in class Output:SQLite. If the value of field Option in class Output:SQLite is set to "SimpleAndTabular", then database tables related to the tabular reports will be included.

There are more than 30 tables in the SQLite output file which contains all of the data found in EnergyPlus's tabular output files, standard variable and meter output files, plus a number of reports that are found in the eplusout.eio output file. The full description for SQLite outputs is described in the EnergyPlus "Output Details and Examples" documentation.

EplusSql class makes it possible to directly retrieve simulation results without creating an EplusJob object which can only get simulation outputs after the job was successfully run before.

However, it should be noted that, unlike EplusJob, there is no checking on whether the simulation is terminated or completed unsuccessfully or, the parent Idf has been changed since last simulation. This means that you may encounter some problems when retrieve data from an unsuccessful simulation. It is suggested to carefully go through the .err file to make sure the output data in the SQLite is correct and reliable.

Examples

# NOT RUN {
if (is_avail_eplus(8.8)) {
    idf_name <- "1ZoneUncontrolled.idf"
    epw_name <-  "USA_CA_San.Francisco.Intl.AP.724940_TMY3.epw"

    idf_path <- file.path(eplus_config(8.8)$dir, "ExampleFiles", idf_name)
    epw_path <- file.path(eplus_config(8.8)$dir, "WeatherData", epw_name)

    # copy to tempdir and run the model
    idf <- read_idf(idf_path)
    idf$run(epw_path, tempdir())

    # create from local file
    sql <- eplus_sql(file.path(tempdir(), "1ZoneUncontrolled.sql"))

    # get sql file path
    sql$path()

    # list all tables in the sql file
    sql$list_table()

    # read a specific table
    sql$read_table("Zones")

    # read report data dictionary
    sql$report_data_dict()

    # read report data
    sql$report_data(name = "EnergyTransfer:Building")

    # read tabular data
    sql$tabular_data()
}
# }
# NOT RUN {
# }