Furthermore , the advent of active filters eased the computation difficulty because sections could be isolated and iterative processes were not then generally necessary .
The difficulties of the image method were firmly put in the past , and even the need for prototypes became largely superfluous .
The advent of active filters eased the computation difficulty because sections could be isolated and iterative processes were not then generally necessary .
The difficulties of the image method were firmly put in the past , and even the need for prototypes became largely superfluous .