How SUMIF function in Excel with brackets and "!" sign works - excel

Question

I have a Macro in my Excel and this Macro writes a formula to one cell in my Excel sheet.
The code of my Macro that does this is like below:
Range("F10").Select
ActiveCell.FormulaR1C1 = "=SUMIF('1'!C2,C7,'1'!C[2])"
and the Formula produced for the F10 cell is like below:
=SUMIF('1'!$B:$B,$G:$G,'1'!H:H)
Can someone help me understand this code? What does '1' , ! , [] and ... do exactly?
In general I want to know what is the output of " =SUMIF('1'!$B:$B,$G:$G,'1'!H:H)" and why the macro generates this formula?

Answer 1

You have chosen unfortunate sheet names.
"=SUMIF('1'!C2,C7,'1'!C[2])"
The '1' is the sheet name. Sheet names can be wrapped in single quotes, but you only need to do that if the sheet name contains a space.
The ! is a separator between sheet name and cell reference.
C2 means column 2, which is column B. You are using R1C1 syntax for the formula, so the C identifies the following number as related to a column.
C7 means the 7th column, so, column G.
'1'! again means the sheet name and the separator.
C[2] means from the current column (the C) go 2 to the right. If the formula returns column H for that, it means that the current cell must be in column F.
R1C1 referencing is not widely used in worksheets these days, but in VBA it makes relative cell referencing very easy. The brackets mean "relative to the current location" and the R or C will determine whether it's a row or column that needs to be traversed.
R1C1 is Row 1, column 1, in other words, cell A1. This is an absolute reference.
R[4]C[-2] is a relative reference. It will be evaluated based on the current cell and from that position will add 4 rows (positive value 4 for rows) and subtract 2 columns (negative value -2 for columns). So, if the current cell is H4, which translates to R4C8, a reference to R[4]C[-2] means F2.

Answer 2

So I'm assuming you know what
=sum($B:$B)
does? If not, then you need to take a basic Excel tutorial before aksing this quesiton.
!
The $B:$B in my formula is the range. It refers to the range that is the enitre column B on the current worksheet. If you wanted to sum up column B on a different worksheet then you specify that range like worksheetname!$B$B or if the worksheet name has spaces in it then use quotes like 'worksheet name'!$B$B.
Hence '1'!$B$B refers to column B on a worksheet named '1'
[]
So what do the square brakcets do? That is from the R1C1 notation. So normally you reference a range absolutely. So when you use a range like $B$B, you are refereing to column B no matter where you call that function from (i.e. no matter which cell your function is in). R1C1 notation is Excel's way of allowing to refer to cells relatively, or in other words refer to their locations relative to the cell your formula is written in. c2 in R1C1 notation is actually still absolute, it means the second column (i.e. B). c[2] is now relative, the [2] means two columns to the right of the cell your formula is in.
SUMIF
SUMIF is an excel formula that only sums up the portion of a range that meets a certain condition. In your case we cannot say what it will output because we don't know what is in your sheet. But basically for
=SUMIF('1'!$B:$B,$G:$G,'1'!H:H)
The '1'!$B:$B is the range of values you want to test your condition against, the $G:$G is your condition (which I think should point to a single cell rather than a range btw...) and finally '1'!H:H is the range of values that you want to sum.
So if you want to sum values in columns H only when the values in column B are greater than 10 and you sheet 1 looks like
B G H
________________
1 | 5 '>10 1
2 | 12 2
3 | 13 3
The result of =SUMIF('1'!$B:$B,$G:$G,'1'!H:H) will be 5 (i.e. adding 2 and 3 from column H because in column B 12 and 13 were larger than 10 but 5 was not and thus does not meet the criteria for being part of the sum.