Re: Worldmap mercator projection - Latitude to Y calculation. - last try

On Fri, 1/23/2026 1:56 PM, R.Wieser wrote:
> EllisMorgan,
> 
>> I would expect most people would think that log(A) means log to base 10 of 
>> A while ln(B) is natural log of B if they were just shown without any 
>> explanation.
> 
> As I mentioned, I googled for what "ln()" could mean.  I got information 
> back that different professions use "log()" to mean whatever they want it to 
> mean.   :-(
> 
> I did however find how to use "log()" to emulate "ln()" (as I showed in my 
> first message).  Alas, the result was still not near the expected one.
> 
> If you can point out what mistake(s) I made with that (first) fomule or my 
> conversion of it I would be much obliged.
> 
> Regards,
> Rudy Wieser

If you take a math course, you're taught it is as Ellis explains.

That the notation ln() is a logarithm based on the constant e = 2.71828 .

And that log() is log base 10.

*******

And just scraping a calculator web page gives a definition
with a superscript power y and a subscript base b as
a way of declaring other bases for a logarithm. For example,
in computer design, you might want a log base 2, as the
computer is binary for some things it does. You could
change the subscript to "e" or even the PI symbol if you wanted.

        y
   x = b  ; then y = log (x); where b is the base
                        b

We could write

   ln(x) = log (x)
              e

and I'm writing it this way so plain ASCII will do the job.

But when it comes to computers and math, some languages
allow entry of natural expressions, to at least make it
kinda look like math. Fortran and C butcher math,
and C++ is a little better.

   Paul