ios - Sending float to parameter of incompatible type id -

i'm in middle of creating button uses core data save name, xcoordinate, , ycoordinate of point annotation. can persist name, keep getting error when try save coordinate. i've logged correct data, can't seem save it.

when try setvalue newpoi, error reads: sending 'float' parameter of incompatible type 'id'.

in data model, attribute set float. self.latitude , self.longitude of type float.

my method little rough because i'm relatively new this, appreciate feed give me concerning error. below code method. don't understand 'id' comes play here.

-(void) saveselectedpoiname:(nsstring *)name withy:(float)ycoordinate withx:(float)xcoordinate{     self.pointfrommapview = [[mkpointannotation alloc] init];     self.annotationtitlefrommapview = [[nsstring alloc] init];      appdelegate *appdelegate = [[uiapplication sharedapplication] delegate];     nsmanagedobjectcontext *context = [appdelegate managedobjectcontext];      self.annotationtitlefrommapview = name;     self.latitude = ycoordinate;     self.longitude = xcoordinate;      nsentitydescription *entitypoi = [nsentitydescription entityforname:@"poi" inmanagedobjectcontext:context];     nsmanagedobject *newpoi = [[nsmanagedobject alloc] initwithentity:entitypoi insertintomanagedobjectcontext:context];     //create new poi record     [newpoi setvalue:name forkey:@"name"];     [newpoi setvalue:ycoordinate forkey:@"ycoordinate"]; <---error happens here ycoordinate.      nserror *saveerror = nil;      if (![newpoi.managedobjectcontext save:&saveerror]) {         nslog(@"unable save managed object");         nslog(@"%@, %@", saveerror, saveerror.localizeddescription);     } } 

nsmanagedobject attributes in core data must object , not of primitive type. in case our ycoordinate of type float. in order setvalue: of float type must first wrap value in nsnumber.

[newpoi setvalue:[nsnumber numberwithfloat:somefloat] forkey:@"ycoordinate"]; 

vs.

[newpoi setvalue:somefloat forkey:@"ycoordinate"];