b .+ 2 creates a new array, which then b is assigned to.
On Friday, May 30, 2014 12:32:00 PM UTC+3, paul analyst wrote: > > I see, but what is the difference between: > > b [2,3] = 3 > and > b = b.+2 > > Paul > > > W dniu 2014-05-30 10:11, Tomas Lycken pisze: > > @Paul, > > Try > > julia> a = ones(5,5); > julia> b = a; > julia> b[2,3] = 2; > julia> a == b > true > > On Wednesday, May 28, 2014 9:22:26 PM UTC+2, Jameson wrote: >> >> b+3 is not the same as a (or b, from the prior stage, for that matter). >> It doesn't matter whether a and b are numbers or matrices, large or small >> >> On Wednesday, May 28, 2014, paul analyst <[email protected]> wrote: >> >>> Thx, >>> I'm surprised. I suspect, and I did: >>> a = ones (5,5) >>> b = a >>> b = b +3 >>> a == b >>> false >>> That is not the case for small and large objects? This is not OK :/ >>> >>> W dniu środa, 28 maja 2014 21:11:12 UTC+2 użytkownik Patrick O'Leary >>> napisał: >>>> >>>> > FSbis=FS >>>> >>>> This binds the identifier FSbis to the same memory that FS is bound to, >>>> so the identifiers are aliases for one another. >>>> >>>> If you want FSbis to start out initialized to the same values as those >>>> in FS, but be a separate container, use `FSbis = copy(FS)`. >>>> >>>> On Wednesday, May 28, 2014 2:07:38 PM UTC-5, paul analyst wrote: >>>>> >>>>> Code running back? what happens? >>>>> I have a array FS >>>>> >>>>> >>>>> julia> println(sum(FS)); >>>>> 9.8267205e7 >>>>> >>>>> julia> l,m=size(FS); >>>>> >>>>> julia> FSbis=FS; >>>>> >>>>> julia> >>>>> >>>>> julia> >>>>> >>>>> julia> for i=1:l; #println(i) >>>>> if w[i]==1 us=hcat(F[i,:]',[1:1:m]); >>>>> us=sortrows(us, by=x->x[1],rev=true); >>>>> for j=1:m >>>>> if in(us[j,2],Su) FSbis[i,us[j,2]]=us[j,2]; break >>>>> end; >>>>> end; >>>>> end; >>>>> end; >>>>> >>>>> julia> >>>>> >>>>> julia> println(sum(FSbis)); >>>>> 1.03295914e8 >>>>> >>>>> julia> >>>>> >>>>> julia> println(sum(FS)); >>>>> 1.03295914e8 >>>>> >>>>> >>>>> after the code array FSbis changing and well. But the array FS too is >>>>> changing! Why? Compare sum(FS) before and after. >>>>> Paul >>>>> >>>> >
