Re: imaginary unit

[Dmitri A. Sergatskov]

On 4/27/06, Przemek Klosowski <address@hidden> wrote:
>    On 4/26/06, Przemek Klosowski <address@hidden> wrote:
>    > Perhaps the use of predefined 'i' should elicit a warning?
>
>    That would be a rather annoying warning. Octave is built with
>
> Agreed, of course; the ideal warning would only happen when you
> use 'i' as an imaginary unit---but of course Octave has no way
> of knowing your intentions. Perhaps warning should trigger when
> 'i' (et al) is changed _away_from_ the imaginary unit? That would
> only trigger once.
>

The mess is not limited to variables.
You can also overwrite thinks like rand:
octave:1> rand=3
rand = 3
octave:2> rand(10)
error: invalid vector index = 10

It can also bite you the other way -- you forgot to define
a variable "ss" (stands for "sum squares") and then do:

if (ss <1) disp ("Hi!") end if

with the following result:

usage: retsys = ss  (a,b,c{,d,tsam,n,nz,stname,inname,outname,outlist})
error: evaluating if command near line 193, column 3
error: called from `ss' in file `/usr/share/octave/2.9.5/m/control/system/ss.m'
error: evaluating binary operator `<' near line 1, column 8
error: if: error evaluating conditional expression
error: evaluating if command near line 1, column 1

(this is an actual buglet in leasqr.m)

This is a mess, but I guess we have to live with this.

Dmitri.
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