"In Simulink, seeing a label on your signal lines is crucial for debugging multi-element data flows. By default, Simulink may treat 8-element vectors as '1-D' signals (labeled simply as '8').
If "1x8" refers to a in a fitness release like BodyPump 93: Review: The Perfect Transition Count See 1x8
To force the display to show 1x8 , go to the Constant block settings and uncheck 'Interpret vector parameters as 1-D.' "In Simulink, seeing a label on your signal