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dirbax

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Hi , I am working on some math stuff and I need to check some points ,

so are theses formulas correct ?

 

ISZ(x) : is it 0 ?

 

isz (x) = cos ( pi * ( (2*ceil( abs(x) ) + 1)) / 2 ) / cos(1)

 

Ins : Real number x

 

Out : 1 if x=0 , 0 if x <> 0

 

---------------------------------------------------------------

 

SGN(x) : Sign

 

sgn(x) = abs(x) / ( x + isz(x) )

 

Ins : Real number x

 

Out : 1 if x>0 , 0 if x = 0 , -1 if x < 0

more here

Dirbax

 

thanks

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For one abs() isn't smooth, at all, neither is ceiling().

 

And why don't you want the way a function is presented to be semantic? It's not like you're saving on computability, trig functions are clearly more expensive than a check for properties that are written into the way a number is stored.

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For one abs() isn't smooth, at all, neither is ceiling().

True , I am still working on it in order to minimise the number of functions such as ceil and abs which use semantic definition .

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Again, what's wrong with a semantic definition? If makes things possible to read, as well as computationally cheaper, what could possibly be wrong with it?


Merged post follows:

Consecutive posts merged

And it just occurred to me, if you're trying to define discontinuous functions as compositions of continuous ones, it can't be done.

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