Excel dates - converting different date formats into a single format - excel

Have a large raw data dump and I am trying to format the dates into a consistent format.
As you can see from the screenshot, there are two main formats, one custom mm-dd-yyyy hh:mm AM/PM and mm/dd/yyyy hh:mm:ss. One is stored as general, while the other as a custom value.
I've tried to =left(A2,8), converting via text() and using text to columns, but can't bring the values to a consistent value.

It appears that your Windows regional settings for Short Date are DMY or similar. It is likely your data dump is in MDY format. That is why A2 and A4 are being converted to "real dates" (although incorrectly), and A3 is not since Excel does not know what do with month = 13. You will note that A2 is 1-Dec-2015 and I suspect that in the original data it is 12-Jan-2015.
EDIT: To expand a bit on the explanation. When something that looks like a date or time is entered into an Excel cell, Excel tries to change the result to a date, parsing the input according to the Windows Regional Short Date format. This sometimes has an undesireable outcome. For example, if your Windows Format is MDY but the date is input as DMY, input with days <=12 will be converted incorrectly, and input with days > 12 will be retained as text. This behavior cannot be "turned off" and causes many complaints from those who want to enter data that looks like a date, but is not. (For example, entering an odds ratio as 1-10 or 12:3 will get converted to a date or a time)
Several options
Change the output of the data so as to have the dates in DMY format.
Instead of OPENing the data file, do a Text Import. In later versions of Excel, you will find this on the Data Ribbon ► Get External Data ► From Text. This will open the Text import wizard and allow you to specify the MDY format of the incoming data before Excel transforms it.
After you have done one of the above, the result will be a "real" Excel date or date/time and you can format it how you like.

Write a IF() where if column B specifies "Custom" change format to standard.
For AM, just remove it(replace AM with nothing). For PM add 12 to the hours and replace PM with nothing.
For custom Replace - with / and append :00 to add the seconds to the custom ones too.

Related

Operations time durations in Excel

I am working on a datasets in Excel in which I have a column named Duration containing values such as 11:01, 01:39:13 etc. The format here is either hh:mm:ss or mm:ss. How can I do operations such as addition & subtraction on such values?
The file is of XLSX format & I am working on the latest version of Office.
Most likely your "times" are actually text that look like times. They will need to be converted to actual times to be summed.
The issue is that if one does a straight conversion on 11:01 Excel will assume hh:mm not mm:ss
So we need to add some parsing to get the correct time format then sum the results:
=SUMPRODUCT(--RIGHT("00:"&B2:B4,8))

Getting uniform date format from xlsx file in nodejs

I am reading data from an excel sheet and the 5th column is a date field. I have the following logic to ensure that the input date is converted to YYYY-MM-DD format -
var valid_from = new Date(data[counter][5]);
valid_from_new = var formatedDate = moment(valid_from).format("YYYY-MM-DD");
reqBody.valid_from = valid_from_new.toString();
I have the date 2017-10-10 to begin with and I am able to read it fine via my node app. It works for me as long as I do not edit this field in my Microsoft Excel 2010. If I edit it or simply find/replace the values, I get unix default date (1970-01-01) in reqBody.valid_from.
To find out what happens after the replacement, I checked that if I replace 2017-10-10 with 2017-10-20 and then "clear formats" (excel utility), I get 43028 displaying in the sheet, whereas for the date 2017-10-10 it remains the same, i.e. 2017-10-10. I don't understand why excel behaves like this.
Can this be handled uniformly by my application? I just want to make the "YYYY-MM-DD" format work across any excel versions. It would be fine if I could do one format change or clear format once before feeding the file and it would work.
I don't understand why excel behaves like this.
Excel behaves like that as it stores 2017-10-10 as a serial date. Meaning it is an integer representing the number of days that have past since January 1st 1900 for the Windows system. (potentially 1905 or something similar for mac). In your specific case its apparently 43028. It displays a converted date in a format people read as 2017-10-10 in your case. You will note this as your formatting for the cell is either a date of some sort or a custom user format. If you entered the date as text by leading it with a ' you would note the format does not change when you change the cell formatting. The date is actually just text and not a formatted date. Numbers that are enter in a format that looks like a date to excel, excel will usually attempt to automatically convert them to a serial date value for you. It has a built in list of formats it looks for and I believe also looks at your system settings format too.
As a side note, the decimal portion of the number represents time. Fraction of a day. 0 is 00:00:00 and .5 is 12:00:00.
Can this be handled uniformly by my application?
I am sure the answer to this is "yes" but is beyond my expertise. I highly suspect it is because your code is handling it as text initially. Things go wrong when it receives the integer from excel that represents the date in excel.

Wrong format of a cell in Excel

I am copying large tables from a website to Excel and it is copied in a wrong format. The number which I need seems to be in a cell but when I click into the cell it shows me that it is a date (and the number shown in the cell is its month and year).
Is it possible to change that so that the number in the cell will be 4.25 instead of 1.4.2025?
Thanks a lot.
You can change the format by highlighting the cells, right clicking selecting the format cells option. It will not change the string of numbers from 1.4.2025, but you will be able to replace the date format with something more appropriate for your needs. *
In the 1900 date system, 1.12 and 12.15 (for example) if entered as 1/12 and 12/15 respectively (where the locale has . as the decimal separator) into cells formatted General will show 01-Dec and Dec-15 respectively. The underlying number however (ie change format from Custom to Number) is 42339 for both. 42339 in Short Date format shows as 01/12/2015.
Although generally possible to deduce what malformed number gave rise to what looks like a date it is not always possible to do so. Ambiguity is greatest where the digits for the decimal or integer parts are less than 13. In addition, the locale in which the numbers were entered may play a part (since, in the 1900 date system, 3/4 for example would be interpreted as 42097 where the date convention is DMY 'UK' and 42067 where the date convention is MDY 'US').
So the answer to your question:
Is it possible to change that so that the number in the cell will be 4.25 instead of 1.4.2025?
is "Yes, but not fully reliably" (and even so would require knowledge or guessing of locale, date system and time of the conversion). Since you are "copying large tables from a website to Excel" it seem you retain access to the source data and I would recommend returning to that. On a small scale manual adjustments may be viable, on a large scale consider importing first to software without such automatic interpretation (eg Word, NotePad++) or, if possible, as character separated values imported as text. Address the delimiters with string handling there and only after that import to Excel or save in Excel format.

.NumberFormat sometimes returns the wrong value with dates and times

It seems that every week or so someone posts a question about dates being converted (corrupted?) to American format. Like many others, I have attempted to help but the problem is elusive. I now wonder if I have discovered the cause.
I am working on an application in which I need to extract data from an Excel worksheet and output it as strings formatted to match the value the Excel user can see. So if the value is “1” formatted to display as “1.00” then I want the string to be “1.00”.
I achieve this effect by testing the cell value to be a number, date or time. If it is, I retrieve the number format and use it to format the cell value so:
With .Cells(Row, Column)
Output string = Format(.Value, .NumberFormat)
End With
In most cases this gives me exactly the output I require. However, sometimes I get American dates and times when the source is formatted as a UK date or time.
After much experimentation with Excel 2003 and Excel 2007, I have discovered the cause. (I do not have access to Excel 2010 but from questions I deduce it has the same problem.) This question is in part intended to reveal this problem to the world because I can discover nothing on the internet to indicate that anyone else has noticed it. (No doubt someone will reply that they googled “xyz” and got the answer immediately.) However, the main purpose of this question is to seek suggestions for obtaining the result I need in all situations.
Typically I enter dates as, for example, “23mar12”. Excel recognises this as a date and formats it as “23-Mar-12”. I can select Format Cells and enter or select a custom format or select one of the date formats so I can have any format I can imagine wanting including non-English names for days and months.
However, in one case the format I select is not the format that is recorded: Custom format “dd/mm/yyyy” is recorded as Date format “* 14/03/2001”. This is not obviously a problem until further down the line.
I created a column of dates and times and formatted each with a different custom or standard format. I wrote a macro to extract the NumberFormat for each of these dates and times and write it as a string to an adjacent column. I also formatted the value using the number format and wrote that string to a third column.
In a number of cases the format selected and recorded by Excel was not the format returned by NumberFormat:
Excel format NumberFormat
Date: * 14/03/2001 m/d/yyyy
Date: * 14 March 2001 [$-F800]dddd, mmmm dd, yyyy
Date: 14/03/2001 dd/mm/yyyy;#
Date: 14/03/01 dd/mm/yy;#
Date: 14/3/01 d/m/yy;#
Date: 14.3.01 d.m.yy;#
Date: 2001-03-14 yyyy-mm-dd;#
Date: 14 March 2001 (1) [$-809]dd mmmm yyyy;#
Date: 14 March 2001 (2) [$-809]d mmmm yyyy;#
Custom: hh:mm:ss h:mm:ss
Time: * 13:30:55 [$-F400]h:mm:ss AM/PM
Time: 13:30:55 (1) hh:mm:ss;#
Time: 13:30:55 (2) h:mm:ss;#
Time: 01:30:55 PM [$-409]hh:mm:ss AM/PM;#
Time: 1:30:55 PM [$-409]h:mm:ss AM/PM;#
The values (1) and (2) in the Excel format column were added by me to indicate that there are two apparently identical formats. As can be seen from the NumberFormat column, in each case the second version suppresses a leading zero.
Most changes have no important effect. “[$-F800]” and so on are apparently dummy values with no effect. Apparently you can replace “F800” with an Microsoft country code to have the names of days and months translated to the language of that country.
However, the three standard formats that Microsoft marks with an asterisk are changed unacceptably. The dates are changed from little endian to middle endian; the time is changed from 24 hour to 12 hour and the day of the week has been added to “* 14 March 2001”.
The asterisk against the dates, references the comment: “Except for items that have an asterisk () in the Type list (Number tab, Format Cells dialog box), date formats that you apply do not switch date orders with the operating system.” The asterisk against the time, references the comment: “Except for items that have an asterisk () in the Type list (Number tab, Format Cells dialog box), time formats that you apply do not switch time orders with the operating system.”
If I have to, I can warn my users that standard date and time formats may not give the result desired. However, if they want the popular format “dd/mm/yyyy”, they cannot have it. “dd-mm-yyyy”, for example, is OK but custom format “dd/mm/yyyy” becomes date format “* 14/03/2001” becomes “m/d/yyyy”.
Returning to my opening point: is this strange handling of one particular date format the reason so many people claim their dates are sometimes being converted to American format and is this why the problem is so elusive? I have come across this type of problem elsewhere of one group of Microsoft programmers not knowing what another group are doing. Is this why some functions always work and other sometimes don’t? Some Microsoft programmers know where to look for the correct format and others don’t?
More importantly, for me, can anyone suggest:
How I obtain the true date or time format?
Some other way of determining the user’s chosen display format for a date or time?
BTW 1: I recall that thirty or so years ago I was told that the American military do not use month/day/year format; only American civilians use this format. Can anyone tell me if this is true?
BTW 2: The similar problem is with Excel colours. Excel holds its colours as "ggbbrr" while everybody else holds them as "rrggbb". The programmers for the .Net Excel inter-op were not told and and did not reverse the Excel colour number before using it to control the screen.
I have mainly come up against formatting and date issues when opening text files which have been saved with different regional settings. Two useful cell properties for dealing with this are:
.Text returns the cell value as it is displayed
.Value2 returns the unformatted cell value or date serial number.
As you say, standard date and number formats depend on windows regional settings and this may not be desired behavior as the same workbook can display differently in different regions. MS introduced the regional code prefixes in number formats (circa Excel 2000?) which enforce consistent display if needed but they need to be explicitly selected.
If you really want to see a date or number as the user entered it, you could extract the contents of the .xlsx file looking at the worksheet cell format and the shared strings xml definitions which list the number formats in the saved workbook. I don't really see a need to do this though as the underlying value is stored internally as a serial number and this will not change.
BTW 1: It's been almost 30 years since I was in the military...
I worked on helicopters and I was taught to use a format such as this in the aircraft logbooks: 3 Apr 12. So, that's how I still write dates. This way, there's no wondering about 4/3/2012 - is it April 3 or March 4?
I hacked this: I rewrite the original data in a known format. it relies on DateSerial and TimeSerial:
'Google spreadsheet stores dates in USA format (MM/DD/YYYY). We're in Australia, using DD/MM/YYYY, so we need to swap them.
'
With dc 'the cell who contains a date in USA format.
d = .Value 'capture value in USA format
t = TimeValue(d)
.NumberFormat = "dd/mm/yyyy" 'set to OZ format, so Excel knows the values were swapped in its internal math.
.Value = DateSerial(Year(d), Month(d), Day(d)) 'DateSerial takes y,d,m. We swap Month and Day components, to get OZ format dates
.Value = .Value + TimeSerial(Hour(t), Minute(t), Second(t))
dc.Font.Bold = True ' We bold the cells that are swapped, for debugging
End With
End If

How to create and assign a Custom Format of date and time to an entire column in excel worksheet

I want a customized format(with milliseconds also) in such a way to handle for a date and time in Microsoft Excel.
Sample date and time:
08.25.2010 00:52:09.359
For understanding of above sample date time, it is 25th August 2010 12 hrs 52mins 9seconds 359 milliseconds(AM).
Please provide a custom Format to handle the above mentioned sample date and time and finally to apply for a column.
In Excel 2003 I use the following for time with fractions of second:
"hh:mm:ss,000"
(note: my decimal point is a "," - German)
so a time entered as 12:13:14,1516 will be displayed as 12:13:14,152
Hope this works for you
Edit 28-Nov-2012
I recently migrated to Excel 2010. Special format using up to 3 zero's after a comma for seconds as described above still works. More than 3 zero's however are not accepted.
I'm not certain what you mean by "not recognizing the dates" but the following custom format would give you the format you're looking for. You'll have to adjust the millisecond separator "." according to your localization, of course.
mm.dd.yyyy hh:mm:ss.000
Applying it to a column is as easy as right clicking the column header, selecting Format Cells, choosing Custom on the left and pasting that format string into the Type box.
If you're trying to enter dates in this format, I don't believe that Excel will support that. I don't know of any option to set the date separators to a "." for Excel. Even setting the date format to use dots under the Regional and Language Options doesn't make Excel recognize that.

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