• Registered: 2006-05-29
  • Posts: 30

Topic: Starm Nov calculation not working.

i looked at the book and tried to do the following calculation. maybe you can help me figure out whats wrong?

log with  (subscripted) sqrt (.5)


which looks to me like the log of square root of .5
on  my microsoft excell spread sheet 
log(sqrt(.5))

it comes out to -0.15051499783199.

armor score  = log (sqrt(.5)) *((5+8)/8)*-1

0.24458687147698

ive done this calc over and over... it always comes to the same thing.

whats wrong?

  • Registered: 2005-06-08
  • Posts: 760

Re: Starm Nov calculation not working.

I was also having trouble entering this.

I was advised to enter it this way.

=LOG(((Armor+Hull)/Armor);0.70711)*-1

Paul

  • Registered: 2006-05-29
  • Posts: 30

Re: Starm Nov calculation not working.

OldnGrey wrote:

I was also having trouble entering this.

I was advised to enter it this way.

=LOG(((Armor+Hull)/Armor);0.70711)*-1

Paul

Yes thats sort of different than what the book indicates.

where you have semi colon, you probably mean a * multiplies, yes?

  • Registered: 2005-06-08
  • Posts: 760

Re: Starm Nov calculation not working.

No.
The book example works on a scientific calculator but a spreadsheet does not work in the same way.
The above does give the correct answer in a spreadsheet.
To see this, look at shipyard nova (Ship cell B121) which gives the armor score.

Paul

  • Registered: 2011-03-11
  • Posts: 15

Re: Starm Nov calculation not working.

to calculate a logarithm one needs two values: the BASE of the logarithm and the number of which to calculate the logarithm.

scientific notation: [size=150]log[/size][size=85]2[/size] [size=150]8[/size] = 3, because of [size=150]2 ^ 3 = 2*2*2[/size] = 8, where 2 is the base of the logarithm. (sorry, no [sup] and [sub] here.)

most calculators use the keys "log" for [size=150]log[/size][size=85]10[/size] x and "ln" for [size=150]log[/size][size=85]e[/size] x for the 10th and e-th logarithm (with e=2.718...). (http://www.gruenspar.de/media/catalog/product/c/0/c001712a_9.jpg)

to calculate a logarithm of base 2 like [size=150]log[/size][size=85]2[/size] 8 = 3 on such calculators, you have to type this:
"log 8 / log 2" or "ln 8 / ln 2" both equals "3" due to the calculation laws of logarithms. (see also: http://en.wikipedia.org/wiki/Logarithm#Change_of_base )

in S:NE there are logarithms of base sqrt(0.5), so "log(X) / log(sqrt(0.5))" have to be typed on a calculator*.

*) modern ones uses the algebraic notation, so one can type "log" + "X" ...
older ones uses log as a suffix-notation, so one have to type 1) "X"  2) "log"


greetings
dan
(sorry for the bad english)