Naturally there are ordinary numbers like age (50 etc.), but there are also dates like first visit etc. I would like to apply the same style to every sheet.
However, numbers I can set ONLY to "Date", ...
No: if you want numbers to be numbers and to display as numbers, you would set the cell format to Number. There is surely no rationale is setting the format of such cells to Date?
... in which case "50" suddenly turns into some incomprehensible figure, ...
I don't understand this. You would fail to see 50 only if you had chosen some unsuitable cell format.
... or to "Numbers", in which case then the date is converted into a number that does not make any sense to me (although by now I know, there is a rationale behind that number).
For cells containing dates, you would want the cells to be formatted as Date (or conceivably Text).
Is there a way to set up a cell style (page styles do not have any settings for numbers, fonts etc.) that can handle BOTH standard numbers and dates?
Yes: that is the default situation. If you enter a number it will be saved as and be displayed as a number. If you enter something that LibreOffice recognises as a date, it will be saved as and displayed as a date - with the cell format being automatically changed to Date.
Or do I have to format every single column in every single sheet by hand?
Yes and no. Generally, you will *want* to do this. Being able to set different cell formats for different types of data is a useful feature of spreadsheet programs - not something to be avoided or worked around. Using cells styles can be a good idea, but you cannot expect a single cell format to serve all purposes. If it could, there would be no point in different cell formats existing.
Here's a idea. What you appear to need to do is to duplicate the cell formats that you have arranged in one sheet in other sheets. How about this?
o With the original sheet displayed, go to Edit | Sheet > | Move/Copy... (or right-click the sheet tab and select Move/Copy Sheet...)
o Select Copy and choose where to place your new sheet.
o On the new sheet, delete the data to leave a sheet with identical cell formatting. You can do this in various ways. You may wish to retain column headings and other data. You may wish to retain formulae: do this using Edit | Delete Content... (or press Delete) rather than Backspace and then choose in the Delete Contents panel exactly what you want done.
I trust this helps.
Brian Barker
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