is normally strictly limited making it feasible to store a list of the sizes in which each size is identified for example by a number in the course of knitting the control system instructs the yarn feeder regarding which loop to use and when in time knitting should be performed the time and operation can be synchronized using a time signal to set clocks or simply by sending a signal prior to the start of a new knitting cycle that is 500 times per second in the example described above the yarn feeder should for example supply 2 mm of yarn for each small loop and 8 mm for each large loop to be knitted a small addition or subtraction may also be made each time the loop size is changed due to the special yarn geometry which may prevail during the changeover period due to the properties of the material this variation may differ during a change from 2 to 8 mm compared with a change from 8 to 2 mm however the difference is normally so small as to be negligible the yarn feeder is supplied with information regarding the loop size yarn consumption in good time before the knitting.