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iOS Objective-C Basics (Retired) Foundation Framework NSNumber

Print the result of the 'planck' variable using NSLog where the output should look like the following: "planck 6.626". (

Print the result of the 'planck' variable using NSLog where the output should look like the following: "planck 6.626". (Remember to use the '%@' format specifier when printing the value of 'planck')

my code was NSNumber *planck = [NSNumber numberWithFloat:6.626]; NSLog(@"planck = %@", planck);

and it says Make sure you are passing a NSString to NSLog. Also, make sure you have the correct format options. %@ is used for objects.

2 Answers

You need to use the stringWithFormat method to turn it into a string (using correct format specifiers) and then use the string that is returned as your param to NSLog.

For example, NSString* formattedNumber = [NSString stringWithFormat:@"%.3f", plank]; NSLog(@"%@", formattedNumber);

NSString* formattedNumber = [NSString stringWithFormat:@"%.3f", planck 6.626]; NSLog(@"planck%@", 6.626); can you tell me what i did wrong? it keep says Make sure you are passing a NSString to NSLog. Also, make sure you have the correct format options. %@ is used for objects.

You are trying to NSLog a float (plank) using the wrong format specifier. %f is for floats. For strings you use%@. Change to %f if you want to print plank.