Hello,
On Friday, March 6, 2015 at 2:22:42 AM UTC+1, Tony Kelman wrote:
>
> > I suppose this is related to + and - being unary operators?
>
> Ding ding. Unfortunately space being the horizontal concatenation operator
> means some operations parse very differently and in highly
> whitespace-sensitive ways depending whether they are inside or outside an
> array literal. Would be nice if that were not the case, but I think we'd
> need another delimiter character aside from , or ; to really separate
> horizontal concatenation from vertical concatenation from list construction.
>
> I've always found the space as operator a kind-of-upsetting thing in
Julia. (I refused to use Python---to my own disadvantage---for many years
because there are semantics in the amount of space used, but I finally got
over that.)
Is it really necessary to have separate operators for horizontal and
vertical list construction? In most other respects, Julia seems not to
treat the second dimension really special. E.g., I've argued for `nrow()`
and `ncol()` because---to me---this is more intuitive than the `size(,
dim)`, but it was very clear in the discussions that this was a wrong way
to think about arrays. So now I actually got used to `size()`.
Do we really use literal matrix construction that often in code? I guess
one would use it for examples, but in these cases, can't we just `hcat()`
the columns?
---david
> julia> j=2; [ 1 +j ]
> 1x2 Array{Int64,2}:
> 1 2
>
> julia> j=2; [ 1 + j ]
> 1-element Array{Int64,1}:
> 3
>
> julia> j=2; 1 +j
> 3
>
> julia> j=2; 1 + j
> 3
>
>
> On Thursday, March 5, 2015 at 4:56:20 PM UTC-8, Amuthan A. Ramabathiran
> wrote:
>>
>> Not sure if this has been discussed earlier... can someone explain whats
>> happening here?
>>
>> julia> b = [ 1 +j for j = 1:5 ]
>> ERROR: syntax: invalid comprehension syntax
>>
>> julia> b = [ 1 + j for j = 1:5 ]
>> 5-element Array{Int64,1}:
>> 2
>> 3
>> 4
>> 5
>> 6
>>
>>
>> This happens with both + and -, but not with * or /. I suppose this is
>> related to + and - being unary operators?
>>
>> Thanks!
>> Amuthan.
>>
>
