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iOS Object-Oriented Objective-C Tying it All Together Cumulative Review

Michael Castro
Michael Castro
11,959 Points
Posted by Michael Castro
Michael Castro
11,959 Points

Finding the average of NSNumbers in an array with a for loop.

Create a float variable called runningTotal. Then, create a for in loop which iterates through the array you created in step 1. When the loop finishes running, the value of 'average' should be the average of the values contained in temp.

variable_assignment.mm 
NSArray *temps = @[@(75.5), @(83.3), @(96), @(99.7)];
float average = 0;
float runningTotal = 0;

for (NSNumber *t in temps, t < temps.count, t++) {
  runningTotal = (runningTotal + t);
  average = runningTotal/temps.count;}

/*
for (NSUInteger *t in temps, t < temps.count, t++) {
  runningTotal += [[temps objectAtIndex:t] floatValue];
  average = runningTotal/temps.count;
}
*/
//NSNumber * average = [temps valueForKeyPath:@"@sum.self"];

1 Answer

sonu dhawan
sonu dhawan
1,989 Points
sonu dhawan
sonu dhawan
1,989 Points 
NSArray *temps = @[@75.5, @83.3, @96, @99.7]; // YOU DON'T NEED TO PUT DECIMALS OR INTS INSIDE PARENTHESIS
float average ; // IF YOU ARE GIVEN  IN THE QUESTION NOT TO INITIALIZE THE VARIABLE "make yourself go exactly with the command what they were asking you to do " . 
float runningTotal ;

for (NSNumber *itemsInTemp in temps) {
  runningTotal += [ itemsInTemp floatValue] ;
}

average = runningTotal/temps.count;