I have a function that returns a vector of structures containing data from an sql database query via rusqlite. It works. Can I fold the "let maxvalue", "let minvalue" and "for loop" functionality into the "let mut closing_values" step by applying additional methods in some way? Or is there simply a better way to go about do this? Any assistance will be appreciated.

pub fn get_closing_values(start_date: &str) -> Result<Vec<ClosingByDate>, CustomError> {

    let db_file_path = "stock_data.db";
    let conn = Connection::open(db_file_path)?;

    let mut stmt = conn.prepare(
       "Select date, fdate, close 
       From data
       Where date >= (:startdate)
       Order By date Asc" 
    )?;

    let row_iter = stmt.query_map(&[(":startdate", &start_date)], |row|
    {
        Ok(ClosingByDate {
            date: row.get(0)?,
            fdate: row.get(1)?,
            close: row.get(2)?,
            min: false,
            max: false,
        })
    })?;

    let mut closing_values: Vec<ClosingByDate> = row_iter
            .filter_map(|item| item.ok())
            .collect();

    let maxvalue: f64 = closing_values.iter().max_by(|a, b| a.close.total_cmp(&b.close)).unwrap().close;
    let minvalue: f64 = closing_values.iter().min_by(|a, b| a.close.total_cmp(&b.close)).unwrap().close;

    for element in &mut closing_values {
        if element.close == maxvalue {
            element.max = true;
        } else if element.close == minvalue {
            element.min = true;
        }
    }

    Ok(closing_values)

}

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