Help about the "--" marking

[eladberko]

I'm using this formula, found it online. Work's great, but, what is the "--" marking do? I've never seen it before in use. ​

SUMPRODUCT(--('CTI '!$E$11:$E$5000=TRIM($B6)),--('CTI '!$J$11:$J$5000=TRIM($I$3)))

thnx !

 

[VoG]

It is used to coerce arrays of False/True to 0/1 that can be multiplied together.

 

[Aladin Akyurek]

I'm using this formula, found it online. Work's great, but, what is the "--" marking do? I've never seen it before in use. ​

SUMPRODUCT(--('CTI '!$E$11:$E$5000=TRIM($B6)),--('CTI '!$J$11:$J$5000=TRIM($I$3)))

thnx !

Expressions like 'CTI '!$E$11:$E$5000=TRIM($B6) are conditionals. We want them to return a set of 1's and 0's instead of a set of TRUE's and FALSE's. The two minusses effect just that. The following is an equivalent rendition:

=SUM(
    IF('CTI '!$E$11:$E$5000=TRIM($B6),
      IF('CTI '!$J$11:$J$5000=TRIM($I$3),
        1,
        0),
      0)

which you need to confirm with control+shift+enter, not just enter.

 

[eladberko]

thanx ! Its make sense now. when can i find a good sourse for all type of marking ( like "--", "$", etc ..) ?