ios - Objective C Converting float to integer produces strange results -

i have float has value 30 core data.

when print value using nslog 30.

nslog(@"the value of float temp %@", [self.detailitem valueforkey:@"credit"]); 

when print value casting float int strange numbers , different result each time log printed:

nslog(@"the value of float temp %d", (int)[self.detailitem valueforkey:@"credit"]);  137978864 122273424 

try

nslog(@"the value of float temp %d", [[self.detailitem valueforkey:@"credit"] intvalue]);