World: r3wp

well, it would also eliminate the performance advantage that ordinals 
apparently give

then we need some flag to be settable for none? strict? none? blk/3

Perhaps we need a way to configure the behaviour we want?

if your data doesn't have none, then you can accept none for a range 
error.

I thought about it too :-) e.g. copy-by-default: true, etc. :-)

I suspect it was a mistake to allow an out of range to return none.

Too late now though ..

Regarding pair and decimals; would it make sense to generalize pair 
further into a new vector datatype, that can be any dimension more 
than one? Examples: 2.4x8.0x5.5 would be a 3D vector with coords 
(2.4; 8.0; 5.5). Like the same idea with tuples, which can be 3 or 
more bytes separated by dots: 255.255.255, 255.255.255.255,... etc.

Or should that be handles with user-defined datatypes?

*handled*

And going further, if we take the vector road, what about matrices?

Support for multi-dimensional vectors and matrices in rebcode might 
lead to something really interesting. ;-)

I think it should be handled natively

but it could get ugly quickly.

The alternative, doing vector- and matrix-math just using decimals, 
can easily be ever uglier.

Imagine having a matrix! datatype:
m: make matrix! 4x4
Then you could find the determinant like for example:
m/determinant
That would be a miracle! :-)

Suddently complicated math can be made very simple.

it would also be a miracle to be able to have a complex! datatype. 
I think electronic engineers would appreciate that

How to submit a suggestion to Carl?

feedback or comment on blog?

or rambo?

geomol, I once had the idea that you could define ISO units as kind 
of datatypes and do scientific calculations on them

my calculator can do that, so why not have it in rebol?

Henrik, give an example!

Geomol, Rambo the suggestion for a vector datatype.

and what about interval computations? :)

Let's stick with 3 dimensions.

well, I'm really not sure about the notation as I haven't given it 
too much thought, so I can't give a valid example, but if you could 
say:

>> 6 / 2
== 3

>> 6 [m] / 2 [cm]
== 300 [cm]

this is no good, but some method to attach units to numbers and variables 
and make REBOL aware of them during calculations

>> $5.00 / 20
== $0.25

Henrik, ah ok. Yes, good idea!

so we can do mixed imperial and si calculations ??

Something like:
ISOm6 / ISOcm2

sure, my HP48 can do that easily

as long there is some definable way to convert between them or make 
some sense from it

the acceleration of gravity would be 9.82 [m/s/s] so units themselves 
are math expressions

It that something for a dialect rather then to be inlcuded in the 
core langauge?

peterwood, quite possibly

we already have money datatypes

why not ones for mensuration

I think it's worth making a concept dialect for scientific math with 
units

Hmm, funny idea. To add 6 meters and 2 UK foot:
SIm6 + UKfoot2
Looks weird. :-)

actually, it would be good to make a ctx-unit to handle units exactly 
like the hp48 does

I often have to calculate BMIs .. and most people know their height 
in feet and inches, but their weight in kgs :(

the hp48 uses an underscore to attach the number to a unit: 6_m / 
23_cm

http://www.apple.com/downloads/macosx/math_science/eurekalc.html
<-- I think that could be done with a dialect...

so many things to do!

that calculator needs a spell checker as well!

well, kintetic energy is that new thing, you know...

Graham, I've made a RAMBO proposal for vector and matrix.