copyFrom(obj) {
        var properties = ['label', 'labelDirection'];
        for (let i = 0; i < properties.length; i++) {
            if (obj[properties[i]] !== undefined) { this[properties[i]] = obj[properties[i]]; }
        }
    }
Function to copy the circuit element obj to a new circuit element
@param {CircuitElement} obj - element to be copied from