Range of Factorial Function

Hi,

For some analysis I am doing, I tried the following LOG(FACT(229)), and it
returned NUM!. I am wondering if 229 is too big a number to compute a
Factorial of ? If so, is there an upper limit (something like FACT function
can be applied for numbers <= 150) for the FACT function ?

Thanks in anticipation,

Rushi Patel

A little experimantation reveals that FACT(170) is the largest possible,
returning a value of 7.2574E+306.


--
Ian
--
"Rushi" <Rushi@discussions.microsoft.com> wrote in message
news:9A23F286-6249-4107-95BF-0E7ACE92E2AC@microsoft.com...
> Hi,
>
> For some analysis I am doing, I tried the following LOG(FACT(229)), and it
> returned NUM!. I am wondering if 229 is too big a number to compute a
> Factorial of ? If so, is there an upper limit (something like FACT
> function
> can be applied for numbers <= 150) for the FACT function ?
>
> Thanks in anticipation,
>
> Rushi Patel

Hi. 229! has 443 digits in it, so it's too big for both the worksheet and
vba. (27! being the max in Vba)
Here's just one workaround:

Function LogFactorial(n) As Double
Dim ans As Double
Dim j As Long
For j = 1 To n
ans = ans + Log(j)
Next j
LogFactorial = ans
End Function

Test:
? LogFactorial(229)
1018.95850224969

Which checks with another program:

Log[229!]
1018.9585022496902

HTH ;>)
--
Dana DeLouis
Win XP & Office 2003


"Rushi" <Rushi@discussions.microsoft.com> wrote in message
news:9A23F286-6249-4107-95BF-0E7ACE92E2AC@microsoft.com...
> Hi,
>
> For some analysis I am doing, I tried the following LOG(FACT(229)), and it
> returned NUM!. I am wondering if 229 is too big a number to compute a
> Factorial of ? If so, is there an upper limit (something like FACT
> function
> can be applied for numbers <= 150) for the FACT function ?
>
> Thanks in anticipation,
>
> Rushi Patel

Ian's experimentation is consistant with the range of a double precision
floating point numer (what excel uses for calculating values)

lol.. sounds like you need a cray!!

Double Data Type


Double (double-precision floating-point) variables are stored as IEEE 64-bit
(8-byte) floating-point numbers ranging in value from -1.79769313486231E308
to -4.94065645841247E-324 for negative values and from 4.94065645841247E-324
to 1.79769313486232E308 for positive values. The type-declaration character
for Double is the number sign (#).


"Ian" wrote:

> A little experimantation reveals that FACT(170) is the largest possible,
> returning a value of 7.2574E+306.
>
>
> --
> Ian
> --
> "Rushi" <Rushi@discussions.microsoft.com> wrote in message
> news:9A23F286-6249-4107-95BF-0E7ACE92E2AC@microsoft.com...
> > Hi,
> >
> > For some analysis I am doing, I tried the following LOG(FACT(229)), and it
> > returned NUM!. I am wondering if 229 is too big a number to compute a
> > Factorial of ? If so, is there an upper limit (something like FACT
> > function
> > can be applied for numbers <= 150) for the FACT function ?
> >
> > Thanks in anticipation,
> >
> > Rushi Patel
>
>
>

Oops. Didn't even think of this:

=GAMMALN(229+1)

1018.95850224964

HTH :>)
--
Dana DeLouis
Win XP & Office 2003


"Dana DeLouis" <delouis@bellsouth.net> wrote in message
news:OsRrjksuFHA.3500@TK2MSFTNGP09.phx.gbl...
> Hi. 229! has 443 digits in it, so it's too big for both the worksheet and
> vba. (27! being the max in Vba)
> Here's just one workaround:
>
> Function LogFactorial(n) As Double
> Dim ans As Double
> Dim j As Long
> For j = 1 To n
> ans = ans + Log(j)
> Next j
> LogFactorial = ans
> End Function
>
> Test:
> ? LogFactorial(229)
> 1018.95850224969
>
> Which checks with another program:
>
> Log[229!]
> 1018.9585022496902
>
> HTH ;>)
> --
> Dana DeLouis
> Win XP & Office 2003
>
>
> "Rushi" <Rushi@discussions.microsoft.com> wrote in message
> news:9A23F286-6249-4107-95BF-0E7ACE92E2AC@microsoft.com...
>> Hi,
>>
>> For some analysis I am doing, I tried the following LOG(FACT(229)), and
>> it
>> returned NUM!. I am wondering if 229 is too big a number to compute a
>> Factorial of ? If so, is there an upper limit (something like FACT
>> function
>> can be applied for numbers <= 150) for the FACT function ?
>>
>> Thanks in anticipation,
>>
>> Rushi Patel
>
>

Since he wanted LOG not LN,

=GAMMALN(229+1)/LN(10)

Bernie

> Oops. Didn't even think of this:

I'm impressed....

> For some analysis I am doing, I tried the following LOG(FACT(229)),
> and it returned NUM!. I am wondering if 229 is too big a number to
> compute a Factorial of ? If so, is there an upper limit (something
> like FACT function can be applied for numbers <= 150) for the FACT
> function ?


Recall that LOG(A*B) = LOG(A) + LOG(B)

So LOG(FACT(229)) = LOG(1)+LOG(2)+...+LOG(229)

In A1:A229, put
=LOG(ROW())

Then in B2 put
=SUM(A:A)

A 1-Cell entry along this same theme might be something like this:

=SUMPRODUCT(LOG(ROW(INDIRECT("1:229"))))

--
Dana DeLouis
Win XP & Office 2003


"Jay" <itsjay_97plus1_DoTheMath@yahoo.com> wrote in message
news:Xns96D3A5290F809qwertyuioplkjhgfdsa@207.46.248.16...
>> For some analysis I am doing, I tried the following LOG(FACT(229)),
>> and it returned NUM!. I am wondering if 229 is too big a number to
>> compute a Factorial of ? If so, is there an upper limit (something
>> like FACT function can be applied for numbers <= 150) for the FACT
>> function ?
>
>
> Recall that LOG(A*B) = LOG(A) + LOG(B)
>
> So LOG(FACT(229)) = LOG(1)+LOG(2)+...+LOG(229)
>
> In A1:A229, put
> =LOG(ROW())
>
> Then in B2 put
> =SUM(A:A)