objective c - Pinch zoom limit in core plot iOS -

i have implement pinch zoom limit in core plot. think method pinch zoom. please should in mehtod:

(bool)plotspace:(cptplotspace *)space shouldscaleby:(cgfloat)interactionscale aboutpoint:(cgpoint)interactionpoint  {     return yes; } 

could please share sample code.

if more concerned resulting plot range rather relative scaling amount (a common case), use delegate method:

-plotspace:willchangeplotrangeto:forcoordinate: 

this method informs plot range change range in parameters. should inspect range, modify needed meet requirements, , return range want plot space use. called before change. there several examples of usage in plot gallery example app.