compare two date value in qlik sense - date

In qlik sense, there are two fields' (Package_Packing_End_Working_Date, Pkg_Wave_Sum_Working_Date) value i need to compare, if equal, then return 1, if not equal, then return 0, the fields store date value.
So my formula, if(Pkg_Wave_Sum_Working_Date = Package_Packing_End_Working_Date,1,0)
but it all return 0, may i know which part is wrong?

Your dates can have a time that could lead to this behavior. You can try to use daystart function if(daystart(Pkg_Wave_Sum_Working_Date) = daystart(Package_Packing_End_Working_Date), 1, 0)

Qlik have several problems when works with dates. Try to force to be a date:
Date(Pkg_Wave_Sum_Working_Date,'dd/mm/yyyy') and then try to do the if sentence. Other solutions is try to convert into number with following sentence:
Num(Date#(Pkg_Wave_Sum_Working_Date, 'dd/mm/yyyy'))
With this sentece you can compare two number with:
if(
Num(Date#(Pkg_Wave_Sum_Working_Date, 'dd/mm/yyyy'))-
Num(Date#(Pkg_Wave_End_Sum_Working_Date, 'dd/mm/yyyy'))=0,1,0)

Related

Trying to build Expression for Table field to sort text dates, some with missing elements

Hi I am a newbie and have a problem I have been trying to solve for weeks. I have a table imported from excel with dates in text format (because dates go back to 1700s) Most are in the format "mmmyyyy", so it is relatively easy to add "1" to the date, convert to date format, and sort in correct date order. The problem I have is that some of the dates in the table are simply "yyyy", and some are empty. I cannot find an expression that works to convert these last two to eg 1 Jan yyyy and 1 Jan 1000 within the same expression. Is this possible, or would I need to do this in two queries? Sorry if this question is very basic - I cannot find an answer anywhere.
TIA
You can do something like:
Public Function ConvertDate(Byval Expression As Variant) As Date
Dim Result As Date
If IsNull(Expression) Then
Result = DateSerial(1000, 1, 1)
ElseIf Len(Expression) = 4 Then
Result = DateSerial(Expression, 1, 1)
Else
Result = DateValue(Right(Expression, 4) & "/" & Left(Expression, 3) & "/1")
End If
ConvertDate = Result
End Function

SSRS - Expression to count the number of dates in a colums

In SSRS,how to count the number of dates present in a column?
I am developing a report where I need to display the total number of dates where Date_of_Delivery.Value is updated in a specific month & also I need to display the same for where Date_of_Delivery.Value is Not updated.
Please insist me.
If you want a count of the number of times a date is in a certain time period, you would use the IFF to perform the check and then SUM the results.
=SUM(IIF(Fields!Date_of_Delivery.Value >= CDATE("01/01/2016") AND Fields!Date_of_Delivery.Value <= CDATE("01/31/2016"), 1, 0)
The IFF will check to see if the Date of Delivery is between two dates and return 1 if true otherwise 0. The SUM then sums up all the results.
You should probably use some Parameters for your date so you can just change the parameters instead of the code in the report.
=SUM(IIF(Fields!Date_of_Delivery.Value >= Parameters!START_DATE.Value AND Fields!Date_of_Delivery.Value <= Parameters!END_DATE.Value, 1, 0)

MatLab cells date format conversion

I have a lot of dates in MatLab (over 2 millions). Al these dates are in a cell array in 'yyyymmdd' format, and I want to convert them to 'yyyy-mm-dd' format and put this result in a cell array (not in a char matrix).
I know that I can use
temp = datestr(datenum(datesArray,'yyyymmdd'),'yyyy-mm-dd'),
and then use
mat2cell(temp, ones(1,n),10),
where n is the number of rows of datesArray (in this case approximately 2 millions) in order to get my result, but this approach is very slow.
So, I want to know a different way to do that.
Regards.
You could avoid for loops by using cellfun, let's say your date cell array is
dates = {'20120101', '20120102', '20120103'}
You can then convert them to your format as
cellfun(#(x)[x(1:4),'-',x(5:6),'-',x(7:8)], dates, 'Uniform', false)
Hope that helps.
If your date format is always "yyyymmdd" and it's in a linear cell array called datesArray, you could maybe do it by accessing the strings in datesArray and transforming them by inserting hyphens and concatenating the string.
for i=1:length(datesArray)
newDatesArray{i} = [datesArray{i}(1:4), '-', datesArray{i}(5:6), '-', datesArray{i}(7:8)];
end
Transform your dates into serial one and keep them! However, here's a solution:
% Create dummy dates (takes 10 seconds on my pc)
tic;d = cellstr(datestr(now-2e5+1:now,'yyyymmdd'));toc
% Convert to char, then concatenate with '-' and back to `cellstr()` (1 sec):
c = char(d);
dash = repmat('-',2e5,1);
c = cellstr([c(:,1:4) dash c(:,5:6) dash c(:,7:8)]);
So here my solution, which i think is quite nice!
dates = {'20120101', '20120102', '20120103'}
And you can convert using this :
cellfun(#(x)regexprep(num2str(x), '(?<=\d{4})\d{2}', '-$0'),dates,'Uniform',false)
The answer is similar to radarhead, but it uses the regexprep function instead.

Vectorising Date Array Calculations

I simply want to generate a series of dates 1 year apart from today.
I tried this
CurveLength=30;
t=zeros(CurveLength);
t(1)=datestr(today);
x=2:CurveLength-1;
t=addtodate(t(1),x,'year');
I am getting two errors so far?
??? In an assignment A(I) = B, the number of elements in B and
Which I am guessing is related to the fact that the date is a string, but when I modified the string to be the same length as the date dd-mmm-yyyy i.e. 11 letters I still get the same error.
Lsstly I get the error
??? Error using ==> addtodate at 45
Quantity must be a numeric scalar.
Which seems to suggest that the function can't be vectorised? If this is true is there anyway to tell in advance which functions can be vectorised and which can not?
To add n years to a date x, you do this:
y = addtodate(x, n, 'year');
However, addtodate requires the following:
x must be a scalar number, not a string.
n must be a scalar number, not a vector.
Hence the errors you get.
I suggest you use a loop to do this:
CurveLength = 30;
t = zeros(CurveLength, 1);
t(1) = today; % # Whatever today equals to...
for ii = 2:CurveLength
t(ii) = addtodate(t(1), ii - 1, 'year');
end
Now that you have all your date values, you can convert it to strings with:
datestr(t);
And here's a neat one-liner using arrayfun;
datestr(arrayfun(#(n)addtodate(today, n, 'year'), 0:CurveLength))
If you're sequence has a constant known start, you can use datenum in the following way:
t = datenum( startYear:endYear, 1, 1)
This works fine also with months, days, hours etc. as long as the sequence doesn't run into negative numbers (like 1:-1:-10). Then months and days behave in a non-standard way.
Here a solution without a loop (possibly faster):
CurveLength=30;
t=datevec(repmat(now(),CurveLength,1));
x=[0:CurveLength-1]';
t(:,1)=t(:,1)+x;
t=datestr(t)
datevec splits the date into six columns [year, month, day, hour, min, sec]. So if you want to change e.g. the year you can just add or subtract from it.
If you want to change the month just add to t(:,2). You can even add numbers > 12 to the month and it will increase the year and month correctly if you transfer it back to a datenum or datestr.

What is the most efficient way to convert an eight digit number to a date?

I am using ColdFusion 9.0.1 and some database that I cannot change.
I am accessing a database that stores a date as an eight digit numeric with zero decimal places like this:
YYYYMMDD
I need to be able to read the date, add and subtract days from a date, and create new dates. I am looking for a ColdFusion solution to efficiently (not much code) to convert the date to our standard format, which is
MM/DD/YYYY
And then convert it back into the database's format for saving.
I need to code this in such a way that non-ColdFusion programmers can easily read this and use it, copy and modify it for other functions (such as adding a day to a date). So, I am not looking for the most least amount of code, but efficient and readable code.
Can you suggest anything that would make this code block more flexible, readable, or more efficient (less code)?
<cfscript>
// FORMAT DB DATE FOR BROWSER
DateFromDB = "20111116";
DatedToBrowser = createBrowserDate(DateFromDB);
writeOutput(DatedToBrowser);
function createBrowserDate(ThisDate) {
ThisYear = left(ThisDate, 4);
ThisMonth = mid(ThisDate, 4, 2);
ThisDay = right(ThisDate, 2);
NewDate = createDate(ThisYear, ThisMonth, ThisDay);
NewDate = dateFormat(NewDate, "MM/DD/YYYY");
return NewDate;
}
// FORMAT BROWSER DATE FOR DB
DateFromBrowser = "11/16/2011";
DateToDB = createDBDate(DateFromBrowser);
writeDump(DateToDB);
function createDBDate(ThisDate) {
ThisYear = year(ThisDate);
ThisMonth = month(ThisDate);
ThisDay = day(ThisDate);
NewDate = "#ThisYear##ThisMonth##ThisDay#";
return NewDate;
}
</cfscript>
First find who ever did the database and kick them in the nads...
Personally I'd Convert with sql so my code only dealt with date objects.
Select Convert(DateTime, Convert(VarChar(8),DateTimeInventedByIdjitColumn))
From SomeTable
As stated by our peers, store dates as dates.
'08/06/2011' could be 8th of june of the 6th of August depending on locale.
20111643 is a valid integer..
Not using a proper date type is just a massive collection of features and bugs that at best are waiting to happen.
You can actually rewrite each function into 1 line of code.
function createBrowserDate(ThisDate) {
return mid(ThisDate,4,2) & "/" & right(ThisDate,2) & "/" & left(ThisDate,4);
}
and
function createDBDate(ThisDate) {
return dateFormat( ThisDate, "YYYYMMDD" );
}
Don't keep dates as strings - keep dates as dates and format them when you need to.
If you can't correct the database to use actual date columns (which you should if you can), then you can use these two functions to convert to/from YYYYMMDD and a date object:
function parseYMD( YYYYMMDD )
{
if ( ! refind('^\d{8}$' , Arguments.YYYYMMDD ) )
throw "Invalid Format. Expected YYYYMMDD";
return parseDateTime
( Arguments.YYYYMMDD.replaceAll('(?<=^\d{4})|(?=\d{2}$)','-') );
}
function formatYMD( DateObj )
{
return DateFormat( DateObj , 'yyyymmdd' );
}
By using date objects it means that any level of developer can work with them, without needing to care about formatting, via built-in functions like DateAdd, DateCompare, and so on.
I'm not a regular expression fan since it's not that readable to me.
Since you're using CF9, I'd typed the argument and specify the returntype of the functions to be even more readable for the next person picking up your code.
First, right after I read the date from DB, I'd parse it to a Date object using parseDBDate()
Date function parseDBDate(required String dbDate)
{
var yyyy = left(dbDate, 4);
var mm = mid(dbDate, 4, 2);
var dd = right(dbDate, 2);
return createDate(yyyy , mm, dd);
}
Once you have the date object, you can use all those built-in Date functoin like DateAdd() or DateDiff().
Call browserDateFormat() right before you need to display it.
String function browserDateFormat(required Date date)
{
return dateFormat(date, "MM/DD/YYYY");
}
Call dBDateFormat() inside <cfqueryparam value=""> when it's time to persist to DB
String function dBDateFormat(required Date date)
{
return dateFormat(date, "YYYYMMDD");
}
One liner :)
myDateString = "20110203";
myCfDate = createObject("java","java.text.SimpleDateFormat").init("yyyyMMdd").parse(myDateString,createObject("java","java.text.ParsePosition").init(0*0));
If you want to parse different patterns, change "yyyyMMdd" to any other supported pattern.
http://download.oracle.com/javase/1.5.0/docs/api/java/text/SimpleDateFormat.html
The ParsePosition is used to say where to start parsing the string.
0*0 is shorthand for JavaCast("int",0) - in the Adobe cf engine, 0 is a string, until you apply math to it, then it becomes a Double, which the ParsePosition constructor supports. Technically, it constructs with an int, but cf is smart enough to downgrade a Double to an int.
http://download.oracle.com/javase/1.5.0/docs/api/java/text/ParsePosition.html