function to be called by the timer
Frequency of the timer to be set (in seconds)
Optionaltag?: stringTag to be applied on the created text display (if present) returns {CCommentaire}
Optionalx?: string | number | CValDynx coordinate of the top button zoom in svg coordinates
Optionaly?: string | number | CValDyny coordinate of the top button zoom in svg coordinates
adds to the top right corner of the figure two zoom buttons syntaxes
addTimerButton(callBack, k)andaddTimerButton(callBack, k, x, y)are allowed too where k is the increase ratio (k > 1) and callBack the used function