Re: CLOCKTABLE multiply time expended by hourly rate?

[Daniel E. Doherty <ded-law@ddoherty.net>]

At Thu, 21 Jul 2011 15:37:55 +0200,
Giovanni Ridolfi wrote:
> 
> Daniel E. Doherty <ded-law@ddoherty.net> writes:
> 
> > That's certainly thinking outside the box, but I don't think it
> > works. 
> 
> Actually, Daniel you don't have to *think*, you've to demonstrate 
> that it works or that it doesn't /tertium non datur/.
> 
> > In your example, 1:09 represents 1/9th in calc's fraction mode,
> > not 1+9/60 which it would have to in order to compute with it.
> Not with GNU/Emacs 23.3 calc.
> 
> If you bill 50 per 1 hour, you bill
> 
> (/ 50 60.0 ) is 0.83 per minute.

Agreed.

> 
> If you bill 1 hour + 9 minutes it is 69 minutes
> 
> (* 0.83 69) 57.269999999999996  = 57.27
> 
> isn't it ?
> 

It is.

> And the fifth column in my table (see below) does compute 57.27 or not?
> 

Not.  At least when I do it.  Here's what I get after recalcing your example.

| Argo Status Hearing <2011-06-28 Tue 09:00> |   |   | 1:09 | 0.09 |
| Letter of Discovery Deficiencies           |   |   | 2:48 | 0.03 |
#+TBLFM: $5=$4*0.83;Df2

Maybe I have a different mode setting or something.  You seem to have
the $4, or 1:09, being interpreted as 69, but I have it being
interpreted as a calc fraction, i.e., 1/9 = 0.11111111.  So 0.83 *
0.111111 gives me 0.9259, which rounds to 0.9.

>    You may say: "Ah but this is only one example, you've been lucky!"
> 

I would.

>  I reply, what about the second line?
> 
> (* (+ 120 48) 0.83) = 139.44
> 
> Calc is *really* smart, isn't it?

Undoubtedly.  Apart from Org, my favorite features of Emacs.  I'm
waiting for vi to duplicate that functionality.

Thanks for taking the time to look at this.

> 
> cheers,
> Giovanni
> 
> >
> > Regards,
> >
> > At Thu, 21 Jul 2011 13:07:28 +0200,
> > Giovanni Ridolfi wrote:
> >> 
> >> Daniel E. Doherty <ded-law@ddoherty.net> writes:
> >> 
> >> > Hi all,
> >> >
> >> > I am trying to use orgmode to bill for time.  My idea is to add a column
> >> > that multiplies the elapsed time column by an hourly rate.
> >> 
> >> what about using a minute rate?
> >> 
> >> (/ 50 60.0) 0.83 so:
> >> 
> >> | Argo Status Hearing <2011-06-28 Tue 09:00> |   |   | 1:09 |  57.27 |
> >> | Letter of Discovery Deficiencies           |   |   | 2:48 | 139.44 |
> >> #+TBLFM: $5=$4*0.83;Df2
> >> 
> >>