open_csv()

Opens an output CSV file, allowing for print_csv() to write values to it.

Synopsis

open_csv(out_filename,"col_1",...,"col_n")

Description

This action creates a CSV output file in the FRED results directory.

Parameters

out_filename

The filename of the CSV to be produced, with its extension.

col_1, ..., col_n

A comma-separate list of header names (in quotes!) to place at the start of the file. Each header name must be a non-empty string of alphanumeric and underscore characters.

Examples

The following prints the value of the likes_baseball agent variable for every ordinary agent ID defined in a file called agents.txt to out.txt.

agents.txt

ID,likes_baseball
123,0
456,1
789,1
999,0

main.fred

simulation {
    locations = none
    default_model = none
    start_date = 2020-Jan-01
    end_date = 2020-Jan-01
}

variables {
    agent numeric likes_baseball
}

condition TEST {
    start_state = Agent_Start
    meta_start_state = Meta_Start

    state Meta_Start {
            read_agent_file(agents.txt)
            open_csv(out.txt,"id","likes_baseball")
            wait()
            next()
    }

    state Agent_Start {
            print_csv(out.txt,id,likes_baseball)
            wait()
            next()
    }
}

Errors

It is a run-time error to call open_csv() more than once on the same file.

See Also

open_file(), print_csv()