How to use [AGSMutablePoint offsetByX:xOffset y:yOffset]

Discussion created by zhangzhb369 on Oct 11, 2013
Latest reply on Oct 11, 2013 by zhangzhb369
[AGSMutablePoint offsetByX:xOffset y:yOffset]

The SDK says:
xOffset : The offset along x coordinate.
yOffset : The offset along y coordinate.

What does offset mean exactlly. Does it mean the International Meter Unit.
Now I want to add 1000 meters in y coordinate.  Here is my code, is it correct:

AGSMutablePoint *point = [AGSMutablePoint pointWithX:webMercatorX y:webMercatorY spatialReference:[AGSSpatialReference spatialReferenceWithWKID:WKID_WGS_1984_WEB_MERCATOR_AUXILIARY_SPHERE]];    //Web Mercator

[point offsetByX:0 y:1000];   //add 1000 meters in y coordinate

Thank you.