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Average Joe The second formula

Now, we could of course turn the notch up a bit, now that we know how formulas work, and go to a harder formula -- but we won't. We'll do a similar formula to =sum(), which is =average(). This formula works in exactly the same manner as =sum() -- it is built the same way, has the same criterions and parameters. The only difference in these two formulas, is what the outcome is. You now know that =sum() give you the sum of any number of, eh, numbers. If you can guess what the =average() formula does, please mail here, and receive a brand new car as a prize... Yes, it gives you the average of any number of, eh, numbers! This is very typical for Calc, in that similar formulas are also very similar to use. This makes it very much easier to learn new formulas -- you only have to learn the new formula name, and use the syntax (= the way that the formula want its input formated) from the similar formula that you already know. Why don't we just use the same figures as last time? Like this: Now, type =average( and remember not to complete the parenthesis: Click and drag from the cell A1 to cell A5, like below: If you now press [enter] to finnish the editing of the formula. Pardon? You on the back, speak up, please! Did I forget to enter the final parenthesis? Hm, yes, you're right. But did we get an error? Nope, Calc guessed that we had finished editing the formula and actually completed the formula for us! If you happened to notice my "error" and put the end parenthesis yourself, you ended up with exactly the same result. Please see the lesson for =sum() for further details on the =average() formula, as they are almost identical in almost every aspect.

The time is now How to let Calc give you time

Sometimes you want to let Calc give you the current time. You could, of course, take a look yourself at the watch, but we’re too lazy today, aren’t we? "Yes we are!". Thanks... The good news is that it’s the easiest formula so far. The bad news is that there aren’t many challenges here -- unless we make them ourselves :-) Now, let’s get on with the formula: =NOW() That is actually the whole, complete formula. Nothing to put between the parenthesis, nothing. That’s it! What this formula will do, is give you the exact date and time, down to the second. But, as with all other formulas, it won’t recalculate until it’s told to. OK, try it now. Go to any cell, and type =NOW() (it doesn’t have to be upper case). Calc will now(!) give you the exact time and date that you pressed [Enter]. If you want it to update the time, double click inside the cell, and press [Enter] again. Or you can press [F2] and hit [Enter]. Or you can go to the Tools -> Cell Contents menu and choose Recalculate.

=LEFT()

Extracting a given number of characters from a cells, counting from left

Sometimes you want to extract and use a portion of the contents of a cell, either number or text. Let me give you an example. Say you have entered birth dates in the following format "yyyy-mm-dd", 2004-03-13. It is quite difficult to extract the year of birth here, especially if you have 13 000 of them... This is where the magic of =LEFT() comes in... Go to cell A1 and enter "Date of birth" -- without the "-s. Enter these numbers in the cells below: Go to cell B1 and enter "Year of birth". As you now can see, the cells A1 and B1 both act as column headings -- they describe what kind of data you expect to find below. Go to cell B2 and type =LEFT(A2;4) and hit [Enter]. By the way: instead of typing A2 above, you can of course use your mouse and click inside cell A2 after you’ve typed =LEFT( Copy down the cells from B2 to the cells B3 and B4. Do this by selecting cell B2 and grab the handle in the lower right corner of the cell and drag it down until you’ve covered B4. What happened? Your cell B2 should now read "2002", correct? Let’s look a bit closer at what happened here... What happens is that you instruct Calc to get the 4 first characters (in this case numbers) in cell A2 from left.

=RIGHT()

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