dumb question

I feel I should know the answer to this, but I don't, and I can't find it in
excel help.

What does "--" do in a formula?

I've seen it used in a few formulas (sumproduct & mmult specifically), and
I've even used it myself when advised to do so, but I don't quite understand
what it does. Can someone explain?

Thanks.

It's a shortcut way to convert a text number into a number value. HTH
Otto
"uw805" <uw805@discussions.microsoft.com> wrote in message
news:4A9A7AF6-37DB-43E0-87F6-1F747B2962E6@microsoft.com...
>I feel I should know the answer to this, but I don't, and I can't find it
>in
> excel help.
>
> What does "--" do in a formula?
>
> I've seen it used in a few formulas (sumproduct & mmult specifically), and
> I've even used it myself when advised to do so, but I don't quite
> understand
> what it does. Can someone explain?
>
> Thanks.

See http://www.xldynamic.com/source/xld.SUMPRODUCT.html for a detailed
explanation.

--
HTH

Bob Phillips

(replace somewhere in email address with gmail if mailing direct)

"uw805" <uw805@discussions.microsoft.com> wrote in message
news:4A9A7AF6-37DB-43E0-87F6-1F747B2962E6@microsoft.com...
> I feel I should know the answer to this, but I don't, and I can't find it
in
> excel help.
>
> What does "--" do in a formula?
>
> I've seen it used in a few formulas (sumproduct & mmult specifically), and
> I've even used it myself when advised to do so, but I don't quite
understand
> what it does. Can someone explain?
>
> Thanks.

-- is used when the function returns values of TRUE or FALSE, but you
need to do math on these results - it works like this

the first - forces Excel to convert the true and false to the numeric
equivalents - but of the OPPOSITE state (so true is now numeric 0 and
false is numeric 1). The second minus converts them BACK again - so 0
is now 1 and 1 is now 0 - this now means that in a function like
=sumproduct(--(a1:a10>10),--(b1:b10<90),c1:c10)

you will get results like
=1*1*ValueInC
if the first two conditions are true

or
=0*1*valueInC
if the first condition is false (extend this as you need to!!!)


uw805 wrote:
> I feel I should know the answer to this, but I don't, and I can't find it in
> excel help.
>
> What does "--" do in a formula?
>
> I've seen it used in a few formulas (sumproduct & mmult specifically), and
> I've even used it myself when advised to do so, but I don't quite understand
> what it does. Can someone explain?
>
> Thanks.

-True becomes -1 (not 0)
--True becomes 1

-False becomes 0
--False stays 0



"aidan.heritage@virgin.net" wrote:
>
> -- is used when the function returns values of TRUE or FALSE, but you
> need to do math on these results - it works like this
>
> the first - forces Excel to convert the true and false to the numeric
> equivalents - but of the OPPOSITE state (so true is now numeric 0 and
> false is numeric 1). The second minus converts them BACK again - so 0
> is now 1 and 1 is now 0 - this now means that in a function like
> =sumproduct(--(a1:a10>10),--(b1:b10<90),c1:c10)
>
> you will get results like
> =1*1*ValueInC
> if the first two conditions are true
>
> or
> =0*1*valueInC
> if the first condition is false (extend this as you need to!!!)
>
> uw805 wrote:
> > I feel I should know the answer to this, but I don't, and I can't find it in
> > excel help.
> >
> > What does "--" do in a formula?
> >
> > I've seen it used in a few formulas (sumproduct & mmult specifically), and
> > I've even used it myself when advised to do so, but I don't quite understand
> > what it does. Can someone explain?
> >
> > Thanks.

--

Dave Peterson

Yes, of course it does - I think my brain stopped working while my
fingers kept typing!
Dave Peterson wrote:
> -True becomes -1 (not 0)
> --True becomes 1
>
> -False becomes 0
> --False stays 0
>
>
>
> "aidan.heritage@virgin.net" wrote:
> >
> > -- is used when the function returns values of TRUE or FALSE, but you
> > need to do math on these results - it works like this
> >
> > the first - forces Excel to convert the true and false to the numeric
> > equivalents - but of the OPPOSITE state (so true is now numeric 0 and
> > false is numeric 1). The second minus converts them BACK again - so 0
> > is now 1 and 1 is now 0 - this now means that in a function like
> > =sumproduct(--(a1:a10>10),--(b1:b10<90),c1:c10)
> >
> > you will get results like
> > =1*1*ValueInC
> > if the first two conditions are true
> >
> > or
> > =0*1*valueInC
> > if the first condition is false (extend this as you need to!!!)
> >
> > uw805 wrote:
> > > I feel I should know the answer to this, but I don't, and I can't find it in
> > > excel help.
> > >
> > > What does "--" do in a formula?
> > >
> > > I've seen it used in a few formulas (sumproduct & mmult specifically), and
> > > I've even used it myself when advised to do so, but I don't quite understand
> > > what it does. Can someone explain?
> > >
> > > Thanks.
>
> --
>
> Dave Peterson

That's never happened to me, well, not in the last 10 minutes!


"aidan.heritage@virgin.net" wrote:
>
> Yes, of course it does - I think my brain stopped working while my
> fingers kept typing!
> Dave Peterson wrote:
> > -True becomes -1 (not 0)
> > --True becomes 1
> >
> > -False becomes 0
> > --False stays 0
> >
> >
> >
> > "aidan.heritage@virgin.net" wrote:
> > >
> > > -- is used when the function returns values of TRUE or FALSE, but you
> > > need to do math on these results - it works like this
> > >
> > > the first - forces Excel to convert the true and false to the numeric
> > > equivalents - but of the OPPOSITE state (so true is now numeric 0 and
> > > false is numeric 1). The second minus converts them BACK again - so 0
> > > is now 1 and 1 is now 0 - this now means that in a function like
> > > =sumproduct(--(a1:a10>10),--(b1:b10<90),c1:c10)
> > >
> > > you will get results like
> > > =1*1*ValueInC
> > > if the first two conditions are true
> > >
> > > or
> > > =0*1*valueInC
> > > if the first condition is false (extend this as you need to!!!)
> > >
> > > uw805 wrote:
> > > > I feel I should know the answer to this, but I don't, and I can't find it in
> > > > excel help.
> > > >
> > > > What does "--" do in a formula?
> > > >
> > > > I've seen it used in a few formulas (sumproduct & mmult specifically), and
> > > > I've even used it myself when advised to do so, but I don't quite understand
> > > > what it does. Can someone explain?
> > > >
> > > > Thanks.
> >
> > --
> >
> > Dave Peterson

--

Dave Peterson