For a project im developing i need to find a diference between two dates to check which is more recent, and i was doing just fine but i found a little bug.
for the dates im using struct tm, this is the code:
it works in every date except when i want to compare a date in the end of the month like (31/5/2016) with the following day (1/6/2016), it returns me 0 days and it should return 1. but if i change it to 30/5/2016 it returns 1 day instead of 2. The thing is may is 31 days not 30.. so it works in some months and in others it doesnt work.. does anyone know how to get past this?
thanks in advance and sorry for my bad english, it isn't my native language
The value 0, not 1, in secondDate.tm_mon will stand for January.
Try this:
struct tm firstDate, secondDate;
firstDate.tm_hour = 0;
firstDate.tm_min = 0;
firstDate.tm_sec = 0;
firstDate.tm_mon = 5 - 1;
firstDate.tm_mday = 30;
firstDate.tm_year = 2016 - 1900; //difference between current year and 1900
secondDate.tm_hour = 0;
secondDate.tm_min = 0;
secondDate.tm_sec = 0;
secondDate.tm_mon = 6 - 1;
secondDate.tm_mday = 1;
secondDate.tm_year = 2016 - 1900;
time_t fDate = mktime(&firstDate); // 31/5/2016
time_t sDate = mktime(&secondDate); // 1/6/2016
int diff = (difftime(fDate, sDate));
printf("%d", diff / 86400);
Related
I'm trying to map the max number of consecutive days with rain <1 mm in Google Earth Engine.
This is the link to the code
https://code.earthengine.google.com/22b5c20d2700a2ffb5989f892838ac58
First I reclassify the collection with 0 if rain <=1 and 1 if >1.
Then I run the code that should count the days of the longest dry period, but it is able to do so only if the dry period reach the end of the time period.
For instance if I am looking for the longest dry period in 4 days timestep i get the following series:
rain days 1 2 3 4 output
0,0,1,1 = 0 dry days
0,1,0,0 = 2 dry days
0 = rain<=1 and
1 = rain>1 (as per the first step)
Does anyone can help in solving this?
Thanks
I don't think you were far off in your code that you provided. To keep track of the dry spells you have to use .iterate(). I took a stab at your application in a little different way where instead of classifying the data before the iteration, I calculate which pixels are dry each day and carry over the accumulated days that a pixel is dry, otherwise it is set to zero:
// DATA
var collection = ee.ImageCollection("UCSB-CHG/CHIRPS/DAILY");
// Define time range
var startyear = 2000;
var endyear = 2017;
var startmonth = 1;
var endmonth = 12;
// Set date in ee date format
var startdate = ee.Date.fromYMD(startyear,startmonth,1);
var enddate = ee.Date.fromYMD(endyear,endmonth,31);
// Filter data
var datain_t = collection.filterDate(startdate, enddate)
.filter(ee.Filter.calendarRange(startmonth,endmonth, 'month'))
.select("precipitation").map(function(img){
return img.addBands(ee.Image.constant(0).uint8().rename('counter'));
})
.sort('system:time_start');
// // START
var dataset = datain_t
.filterDate("2016-08-01","2016-08-30")
.sort('system:time_start:');
print(dataset,"dataset");
var precipThresh = 1; // mm
function drySpells(img, list){
// get previous image
var prev = ee.Image(ee.List(list).get(-1));
// find areas gt precipitation threshold (gt==0, lt==1)
var dry = img.select('precipitation').lt(precipThresh);
// add previous day counter to today's counter
var accum = prev.select('counter').add(dry).rename('counter');
// create a result image for iteration
// precip < thresh will equal the accumulation of counters
// otherwise it will equal zero
var out = img.select('precipitation').addBands(
img.select('counter').where(dry.eq(1),accum)
).uint8();
return ee.List(list).add(out);
}
// create first image for iteration
var first = ee.List([ee.Image(dataset.first())]);
// apply dry speall iteration function
var maxDrySpell = ee.ImageCollection.fromImages(
dataset.iterate(drySpells,first)
).max(); // get the max value
// display results
Map.addLayer(maxDrySpell.select('counter'),{min:0,max:30,palette:'#9ecae1,#ffffff,#ffeda0,#feb24c,#f03b20'},'Max Dry Spells');
Here is the link to the code: https://code.earthengine.google.com/80b4c0f7e82a5f0da316af1d2a55dd59
Don't try to run this analysis for too long of a time period or Earth Engine will give an error. I hope this helps!
I used this simple script from: https://github.com/icambron/moment-countdown to make a simple countdown. The code below i'm using.
Used Code:
$interval(function(){
$scope.nextDate = moment().countdown($scope.nextDateGet,
countdown.DAYS|countdown.HOURS|countdown.MINUTES|countdown.SECONDS
);
$scope.daysCountdown = moment($scope.nextDate).format('dd');
$scope.hoursCountdown = moment($scope.nextDate).format('hh');
$scope.minutesCountdown = moment($scope.nextDate).format('mm');
$scope.secondsCountdown = moment($scope.nextDate).format('ss');
},1000,0);
This gives correct output
$scope.nextDate.toString();
But this contains one string with the remaining days,hours,minutes and seconds. So i decided i want to split this string into 4 strings by using this:
$scope.daysCountdown = moment($scope.nextDate).format('dd');
$scope.hoursCountdown = moment($scope.nextDate).format('hh');
$scope.minutesCountdown = moment($scope.nextDate).format('mm');
$scope.secondsCountdown = moment($scope.nextDate).format('ss');
Example for input
2016-10-15 10:00:00 // $scope.nextDateGet
Desired output is something like this:
0 // (days)
12 // (hours)
24 // (minutes)
30 // (seconds)
But i can't seem to format the remainings days, i get this output:
Fr // Shortcode for the day the item is scheduled => I need the remaining days in this case that would be 0. The other formatting is correct.
The following output was correct if remaining days was not 0:
$scope.daysCountdown = moment($scope.nextDate).format('D');
If remaining days was 0 it would set remaining days on 14 so this work around did the trick:
if(moment($scope.nextDate).isSame(moment(), 'day')){
$scope.daysCountdown = 0;
} else {
$scope.daysCountdown = moment($scope.nextDate).format('D');
}
Any suggestions to improve this code are always welcome.
Can someone think of a way to calculate the Day-of-the-Year and Week-of-the-Year for the Hebrew calendar? I'm using ISO 8601 which can return the Hebrew year, month, day of the month and day of the week. I'm trying to write re-usable code to calculator any Torah portion (Parsha).
Take a look at the hebcal command to do this. There are also ports for JavaScript (shameless plug, it was written by me), Java, and Perl.
This is easy if you can use Java. My library Time4J enables the features you want (in Hebrew calendar):
PlainDate iso8601 = Iso8601Format.parseDate("2018-03-16");
HebrewCalendar hc = iso8601.transform(HebrewCalendar.axis());
int hyear = hc.getYear();
HebrewMonth hmonth = hc.getMonth(); // obtains an enum
int hdayOfMonth = hc.getDayOfMonth();
Weekday hdayOfWeek = hc.getDayOfWeek(); // obtains an enum
int hdayOfYear = hc.getDayOfYear();
int weekOfYear =
hc.get(
CommonElements.weekOfYear(
HebrewCalendar.axis(),
HebrewCalendar.getDefaultWeekmodel()
)
);
System.out.println("year=" + hyear); // 5778
System.out.println("month=" + hmonth); // ADAR_II (technical result, see next line)
System.out.println(
"month=" + hmonth.getDisplayName(Locale.ENGLISH, hc.isLeapYear())); // Adar
System.out.println("day-of-month=" + hdayOfMonth); // 29
System.out.println("day-of-week=" + hdayOfWeek); // FRIDAY
System.out.println("day-of-year=" + hdayOfYear); // 207
System.out.println("week-of-year=" + weekOfYear); // 30
There are many more features, for example taking into account start of day in the evening of previous day (including astronomical calculations of sunset) or hebrew biblical clock time or different numbering schemes for months etc.
Please help me find out what is going on with DevExpress.XtraScheduler control.
Here are some steps I used to run recurrence schedule:
1. Set up schedule:
Appointment apt;
DateTime StartTime = DateTime.Now;
apt.BeginUpdate();
apt.Subject = "weekly";
apt.Start = startTime;
apt.Duration = TimeSpan.FromMinutes(5);
apt.StatusId = 2;
apt.RecurrenceInfo.AllDay = false;
apt.RecurrenceInfo.Type = RecurrenceType.Weekly;
apt.RecurrenceInfo.Start = startTime;
apt.RecurrenceInfo.Duration = TimeSpan.FromMinutes(5);
apt.RecurrenceInfo.Range = RecurrenceRange.NoEndDate;
apt.RecurrenceInfo.OccurrenceCount = 100;
apt.RecurrenceInfo.DayNumber = 0;
apt.RecurrenceInfo.Periodicity = 1;
apt.RecurrenceInfo.WeekDays = WeekDays.Monday;
apt.HasReminder = true;
apt.Reminder.TimeBeforeStart = TimeSpan.Zero;
apt.EndUpdate();
It worked correct in the first week, but it did not fire an event in the next week. I don't know why it is? could you please give me some clues to I can fix them? or because I used the old version (1.1)?
With the set up schedule as above, is it correct?
Please advices. Thank you very much.
I am surprised to see you assign 1 to RecurrenceInfo.DayNumber. At best, this would be ignored with a weekly recurrence. At worst, this would require that your Monday be the first day of the month. Assign 0 or don't assign this property at all.
I have an algorithm which scans through data read from a .csv file(approx 3700 lines) and assess's which trading week of the year each entry is in by running a count++ for every Sunday of that year and assigning the count value as the trading week when the date falls within that week.
It's working but performance is lagging. It is the 3rd function running using Task.Factory.StartNew (I have also tried parallel.Invoke).
Results of timing tests.
before: 00:00:05.58
after: 00:00:23.27
UPDATE
Added break after each trading week is set. Time improved but still slow.
new time: 00:00:15.74
For our purposes the 1st week of the year is week 1(not 0) and is defined as from the first day of the year until the Sunday. If the first day of the year is a Sunday the length of week 1 is 1 day.
private void SetDefiniteWeeks()
{
string FileLoc = FilePath + Market + ".csv";
string[] Data = File.ReadAllLines(FileLoc);
var FileData = from D in Data
let DataSplit = D.Split(',')
select new
{
Date = DateTime.Parse(DataSplit[0]),
ClosingPrice = double.Parse(DataSplit[4])
};
//assign each date to it's relevant week
TradingWeek TW;
List<TradingWeek> tradingWeek = new List<TradingWeek>();
foreach (var pe in FileData)
{
// DateTime dt = pe.Date;
int Year = pe.Date.Year;
string End_of_Week = "Sunday";
int WeekCount = 0;
DateTime LoopDate_Begin = new DateTime(Year,1,1);
DateTime LoopDate_End = new DateTime(Year,12,31);
do
{
if (LoopDate_Begin.DayOfWeek.ToString() == End_of_Week)
{
WeekCount++;
if (LoopDate_Begin.DayOfYear > pe.Date.DayOfYear && LoopDate_Begin.DayOfYear < (pe.Date.DayOfYear + 7))
{
TW = new TradingWeek { Week = WeekCount, Date = pe.Date };
tradingWeek.Add(TW);
break;
}
}
LoopDate_Begin = LoopDate_Begin.AddDays(1);
} while (LoopDate_Begin.Date.ToString() != LoopDate_End.Date.ToString());
}
}
Please help.
UPDATE
NEW TIME
00:00:06.686
A vast improvement. Thanks all for your help.
Revised code:
CalendarWeekRule cw = CalendarWeekRule.FirstDay;
var calendar = CultureInfo.CurrentCulture.Calendar;
var trad_Week = (from pe in FileData
select new TradingWeek
{
Date = pe.Date,
Week = (calendar.GetWeekOfYear(pe.Date, cw,DayOfWeek.Sunday))
}).ToList();
Im not sure if this is what you want but after reading the comments I got the feeling that this might work (?)
var calendar = CultureInfo.CurrentCulture.Calendar;
var tradingWeek = (from pe in FileData
select new TradingWeek
{
Date = pe.Date,
Week = calendar.GetWeekOfYear(pe.Date, CalendarWeekRule.FirstDay, DayOfWeek.Sunday);
}).ToList();
Edit: Changed to CalendarWeekRule.FirstDay since it's (more?) what OP is looking for.
Three quick thoughts:
Why are you only adding one day each time and checking to see if it's Sunday. Surely once you have found your first Sunday you can add seven days to find the next one?
If you order your pes by DateTime before you start then you don't need to restart at the beginning of the year for each one, you can pick up where you left off.
As Nicolas says, break after adding the trading week. No need to go through the rest of the year after you already know what the answer is.
I guess you'll end up with something like this (may or may not actually work, but should be close enough)
TradingWeek TW;
List<TradingWeek> tradingWeek = new List<TradingWeek>();
string End_of_Week = "Sunday";
var orderedData = FileData.OrderBy(x => x.Date)
DateTime LoopDate_Begin = new DateTime(orderedData[0].Date.Year,1,1);
int WeekCount = 1;
while (LoopDate_Begin.DayOfWeek.ToString() != End_of_Week)
{
LoopDate_Begin = LoopDate_Begin.AddDays(1);
}
foreach (var pe in orderedData)
{
do
{
if (LoopDate_Begin.DayOfYear > pe.Date.DayOfYear && LoopDate_Begin.DayOfYear < (pe.Date.DayOfYear + 7))
{
TW = new TradingWeek { Week = WeekCount, Date = pe.Date };
tradingWeek.Add(TW);
break;
}
WeekCount++;
LoopDate_Begin = LoopDate_Begin.AddDays(7);
} while (true); //need to be careful here
}
if I get you correctly, you don't need to look any further as soon as you've added your TradingWeek
So, you can
break;
after
tradingWeek.Add(TW);
You could then even leave out the
&& LoopDate_Begin.DayOfYear < (pe.Date.DayOfYear + 7)
condition since the first part is going to be true only once: for your desired interval.
You might even go for a loopless approach by dividing the number of days since your starting week by 7 - and doing some cleaning up work ;)
Can you get rid of your do loop altogether by calculating the Week Number directly? Something like the accepted answer here.
Following #nicolas78's response, something like this should work
int Year = pe.Date.Year;
DateTime Year_Begin = new DateTime(Year,1,1);
int Jan1DayOfWeek = Year_Begin.DayOfWeek;
foreach (var pe in FileData)
{
int WeekCount = (pe.Date.DayOfYear - Jan1DayOfWeek) % 7 + 1;
TradingWeek TW = new TradingWeek { Week = WeekCount, Date = pe.Date };
tradingWeek.Add(TW);
}
Depending on how DayOfWeek and DayOfYear count, that is from 0 or 1, and how your mod operation work, you may need to tweak the WeekCount computation a bit.
There's a built-in feature to get the week of the year based on the date in .NET. An example is shown below, but it may need some tweaking to fit your business scenario:
System.Globalization.CultureInfo myCI = new System.Globalization.CultureInfo("en-US");
int week = myCI.Calendar.GetWeekOfYear(DateTime.Now.ToUniversalTime(), System.Globalization.CalendarWeekRule.FirstFourDayWeek, System.DayOfWeek.Sunday);
You don't need to count at all - just do a quick calculation. This assumes that a partial week at the start of the year is week 1 and week 2 begins on the first Monday.
List<TradingWeek> tradingWeek = new List<TradingWeek>();
foreach (var pe in FileData)
{
var date = pe.Date;
while (date.DayOfWeek != DayOfWeek.Sunday)
date = date.AddDays(1);
var week = date.DayOfYear/7+1;
var TW = new TradingWeek {Week = week, Date = pe.Date};
tradingWeek.Add(TW);
}