Tim... I just can't say how thank I am to you. Really. Your code is so
advanced. Works perfect.
By the way, the numeration of array after ccall is inversed. Interesting.
Thank you a lot
пятница, 4 ноября 2016 г., 19:23:25 UTC+3 пользователь Tim Holy написал:
>
> As I tried to explain before, Aptrs corresponds to a Ptr{Ptr{T}} *no
> matter how many dimensions you have*. But showing the C code you want to
> use makes your problem vastly clearer: now I know you want a
> `Ptr{Ptr{Ptr{Ptr{T}}}}` for 4 dimensions.
>
> I think you want a recursive solution, something like
> ```
> ptr1d(A::AbstractVector) = pointer(A)
>
> function ptr1d(A::AbstractArray)
> colons = fill(:, ndims(A) - 1)
> ptr1 = ptr1d(view(A, colons..., 1)) # get 1 pointer so we know the type
> Aptr = Array{typeof(ptr1)}(size(A)[end])
> Aptr[1] = ptr1
> for i = 2:size(A)[end]
> Aptr[i] = ptr1d(view(A, colons..., i))
> end
> Aptr
> end
> ```
>
> Then just pass `ptr1d(A)` as the last argument of your ccall.
>
> Best,
> --Tim
>
>
> On Fri, Nov 4, 2016 at 10:07 AM, Alexander Lyapin <lyapinaa...@gmail.com
> <javascript:>> wrote:
>
>> Tim, thank you for reply!
>>
>> Everything was fine when I tried simple 2D array. Then I moved to real
>> problem and got some errors... please check:
>>
>> -----test.c-----
>> #include <stdio.h>
>> double test(double ****param) {
>> return param[1][1][1][1];
>> }
>>
>>
>> ----Julia-----
>> # ar is Array{Float64,4}
>>
>> sz = size(ar)[1:end]
>> Aptrs = Array{Ptr{eltype(ar)}}(sz)
>> for I in CartesianRange(sz)
>> Aptrs[I] = pointer(ar, sub2ind(size(ar), 1, I.I...))
>> end
>> println(ccall(("test","test"),Float64,(Ptr{Ptr{Ptr{Ptr{Float64}}}},),
>> Aptrs))
>>
>>
>> something is wrong here...
>>
>>
>> пятница, 4 ноября 2016 г., 17:19:17 UTC+3 пользователь Tim Holy написал:
>>>
>>> ccall(sym, Void, (Ptr{Ptr{T}},), Aptrs)
>>>
>>> When you pass an array via `ccall`, it takes the pointer of the data,
>>> which is why this produces a Ptr{Ptr{T}} from an Array{Ptr{T}}.
>>>
>>> Best,
>>> --Tim
>>>
>>> On Fri, Nov 4, 2016 at 9:14 AM, Alexander Lyapin <lyapinaa...@gmail.com>
>>> wrote:
>>>
>>>> but in C i have **double, wich is pointer pointer to array.
>>>> Also in link that I gave, there an example for 2D where it is
>>>> Ptr{Ptr{Float64}}
>>>>
>>>> But anyway, could you give an example for ccall in your case???
>>>>
>>>> пятница, 4 ноября 2016 г., 17:05:57 UTC+3 пользователь Yichao Yu
>>>> написал:
>>>>>
>>>>> On Fri, Nov 4, 2016 at 9:22 AM, Alexander Lyapin
>>>>> <lyapinaa...@gmail.com> wrote:
>>>>> > There is a topic:
>>>>> > https://groups.google.com/d/msg/julia-users/EK9oNzzaoAk/kJqagPL0Ku0J
>>>>> >
>>>>> > However could some one give an example how to pass 3-d or 4-d array
>>>>> to C
>>>>> > function.
>>>>> >
>>>>> > I have Array{Float64, 4} and for ccall I use
>>>>> Ptr{Ptr{Ptr{Ptr{Float64}}}} as
>>>>> > Type of parameter. Is there some way to make it more common for
>>>>> > Array{Float64, N}??? Thank you
>>>>>
>>>>> No matter what the dimension is,it's always a `Ptr{eltype(array)}` in
>>>>> C (`Ptr{Float64}` in thiscase) and since it's just a normalpointer,
>>>>> you always need topass the dimensions explicitlyto C in another
>>>>> argumetns.
>>>>>
>>>>
>>>
>
