Hello,
I've been using autofill and noted some things, not so much bugs but queries about the way it works and if it could be better.
1) I enter (e.g.) 2, 4 and 6 into cells B1-B3
2) I then highlight these cells and use autofill to extend to B4-B9, and I get 8,10,12,14,16,18 in these cells - exactly as expected.
3) If instead I extend only to B6 (but leave the selection in place), I get 8,10,12 in those cells.
4) I can then resume the extension to B9, and get 14,16,18 in B7-B9 - as in (2). Again as expected.
Here's where the fun starts:
5) Instead of 2, 4 and 6, I enter 2, 4 and 7 into cells B1-B3.
6) I use autofill to extend to B4-B9 as before. I get 3,5,8,4,6,9 in B4-B9.
#It took me a little while to work out what is going on (when I noticed this I was using less related numbers and wasnt extending so far, so the pattern was less obvious). It seems that each of the cells B1-B3 is incremented by 1 to obtain the fill values for B4-B6, then again for B7-B9.
7) If I repeat step (3) with these values, I get 3,5,8 in cells B4-B6. BUT:
8) when I resume extension to B9, I don't get 4,6,9 but I get 3,5,8 repeated.
#This strikes me as very odd indeed.
Q: Is there a logical reason for this behaviour? Wouldn't it be better if Calc were to use differences and obtain the values 11,16,22,29,37,46 to fill B4-B9?
Aside: I notice Excel doesn't cope well with this situation either - it produces some (fractional values which I haven't analysed).
In any case, surely step 8 should return the same result as step 6 (?).
(OK, that's 3 questions!)
9) starting with a sinle cell, say, 2 in B1, and extending using autofill, the 2 is incremented to 23,4,5.... etc., i.e. there is an assumption that the increment should be 1. Strictly speaking, it should be 0, since a single value doesn't have an incremental value. To obtain a column containing the same figure in all cells, it is necessary to enter the same value twice into adjoining cells.
Q: Is there a good reason for this? It seems to be the wrong way round: after all, to obtain an increment of 2, I would have to enter two values differing by 2 (similarly 3, or any other number); logically by extension to get an increment of 1 it should be necessary to enter two values differing by 1 (and that is exactly how it works in Excel: if I autofill from a single cell, I get that cell's value duplicated throughout the autofill selection).
Something to think about, anyway!
Best,
/Gary