Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
my app needs to store latitude and longitude values parsed from XML into Core Data. Currently, I have a Core Data Model which has these attributes set to type double. The header file for the Model Object has them defined as NSNumber
How can I convert the string stored in my CurrentNodeText variable into the required type for storage in Core Data? Also, is this an appropriate way to store coordinate data in Core Data?
NSString has a
doubleValuemethod that will examine the string to see if it looks like a double and return that value if so (or 0.0 if not).As for whether that’s an appropriate way to store coordinate data: It depends. Binary floating-point numbers cannot precisely represent every number that decimal numbers can. In these cases, they will store something that’s excruciatingly close but which might screw up calculations demanding precision — for example, comparing floats for equality and testing whether one float is less than another will not yield exact results. If the precise number is important, you might prefer to keep the number in an NSDecimalNumber, NSDecimal or NSString.