fci-ecom-get-gpa.js

/*
 *
 * Examples:
 *
 * // Calculate GPA using grades from the current page
 * const gpa1 = newecomComputeGPA();
 *
 * // Calculate GPA with modified grades for MA112 and HU118, and removing CS112
 * const gpa2 = newecomComputeGPA({ "MA112": "A+", "HU118": "B+", "CS112": "" });
 *
 */
const newecomComputeGPA = (courseGradeReplacements = {}) => {
    const grades = { 'A+': 4.0, 'A': 3.7, 'A-': 3.4,
                     'B+': 3.2, 'B': 3.0, 'B-': 2.8,
                     'C+': 2.6, 'C': 2.4, 'C-': 2.2,
                     'D+': 2.0, 'D': 1.5, 'D-': 1.0, 'F': 0 };
    let total_credit_hours = 0;
    return [...document.querySelectorAll('tbody').item(1).children].reduce((acc, tr) => {
        let credit_hours = Number.parseInt(tr.children[3].innerText);
        let course_grade = courseGradeReplacements[tr.children[0].innerText];
        if (course_grade === undefined) {
            course_grade = tr.children[6].innerText;
        }
        let grade_points = grades[course_grade];
        if (!isNaN(credit_hours) && grade_points !== undefined) {
            total_credit_hours += credit_hours;
            return acc + grade_points * credit_hours;
        }
        return acc;
    }, 0) / total_credit_hours;
}