HealthKit: Calculate heart rate average in a day and length of it - swift

Question

Getting familiar with HealthKit and i am trying to find the below by query, but haven't manage to do that yet.
During the same day workout 30 and 60 minutes with moderate heart rate (64%-76%) of max heart rate.
func getAverageHeartRate(forDate date: Date) {
let cal = Calendar.current
let startDate = cal.startOfDay(for: date)
var comps = DateComponents()
comps.day = 1
comps.second = -1
let endDate = cal.date(byAdding: comps, to: startDate)
let heartRateType = HKQuantityType.quantityType(forIdentifier: .heartRate)!
let heartRateQuantity = HKQuantity(unit: HKUnit(from: "count/min"),
doubleValue: Double(arc4random_uniform(80) + 100))
let heartSample = HKQuantitySample(type: heartRateType,
quantity: heartRateQuantity, start: startDate, end: endDate!)
}

Answer 1

Try this. It has a generic routine to get any sample type. You should add error checking;
var hkSampleRecs = [HKSample]()
func getAverageHeartRate(forDate date : Date, minutes : Int, completion : #escaping (Double) -> Void)
{
let calendar = Calendar.current
let endDate = calendar.date(byAdding: .minute, value: minutes, to: startDate)
getDataSamples(dataType : "HKQuantityTypeIdentifierHeartRate", startDate : date, endDate : date, completion :
{
foundEntryCount in
var totalBPM = 0.0
for sample in self.hkSampleRecs
{
totalBPM += (sample as! HKQuantitySample).quantity.doubleValue(for: HKUnit.count().unitDivided(by: HKUnit.second()))
}
var averageBPM = (totalBPM / Double(self.hkSampleRecs.count)) * 60.0
completion(averageBPM)
}
}
func getDataSamples(dataType : HKQuantityTypeIdentifier, startDate : Date, endDate : Date, completion: #escaping (Int) -> Void)
{
var searchPredicate : NSPredicate?
searchPredicate = HKQuery.predicateForSamples(withStart: startDate, end: endDate, options: .strictStartDate)
let limit = 1000000
let requestedQuantityType = HKObjectType.quantityType(forIdentifier: dataType)!
let sampleQuery = HKSampleQuery(sampleType: requestedQuantityType, predicate: searchPredicate, limit: limit, sortDescriptors: [])
{
(query, result, error) in
if error != nil
{
completion(-1)
}
self.hkSampleRecs.removeAll(keepingCapacity: true)
if result != nil
{
for r in result!
{
self.hkSampleRecs.append(r)
}
}
completion(self.hkSampleRecs.count)
}
healthStore.execute(sampleQuery)
}
Call like this with 30 or 60 in the minutes field, set aDate to start time and date;
getAverageHeartRate(forDate: aDate, minutes : 30, completion:
{
average in
}