When I trace to _chipmunk_cffi.py, it is from pymunk._chipmunk_cffi_abi import ffi, lib, lib_path.
So I trace to _chipmunk_cffi_abi.py and it's only lib, lib_path = load_library(ffi, "chipmunk", debug_lib=_lib_debug) but I can't find ffi anymore. So what is that?
I want to see what is doing in space.step(), where can I find this?
Pymunk is not doing the actual simulation itself, but is using a separate c library called Chipmunk for that part. Chipmunk is written in C, and called from the Python code in Pymunk with the CFFI foreign function interface library. I dont think you can trace it directly from the Python side into C-code. Instead if you want to see what it is looking like you can check the c-source directly, for example the step function is here: https://github.com/viblo/pymunk/blob/0d79176cf2fd642bd2ce4005478cb8d6e37c1e9c/chipmunk_src/src/cpSpaceStep.c#L336
Related
I'm trying to use Visual Studio Code to develop Fortran MPI programs. However, while I can successfully build and run them just fine, it would be very helpful for me if I can use intellisense/autocompletion features for MPI (as well as other external modules). I have /usr/lib/openmpi/ (which contains mpi_f08.mod) as part of fortran.includePaths in my settings.json. However, when I use mpi_f08, I get the problem message from VS Code Module "mpi_f08" not found in project. Here is a minimal CMake build example:
! hello.f90
program hello
use mpi_f08
implicit none
integer :: ierror, nproc, my_rank
call MPI_Init()
call MPI_Comm_size(MPI_COMM_WORLD, nproc, ierror)
call MPI_Comm_rank(MPI_COMM_WORLD, my_rank, ierror)
print*, "hello from rank ", my_rank
call MPI_Finalize()
end program hello
# CMakeLists.txt
cmake_minimum_required(VERSION 3.12)
project(hello_mpi)
enable_language(Fortran)
find_package(MPI REQUIRED)
add_executable(hello_mpi hello.f90)
include_directories(${MPI_Fortran_INCLUDE_PATH})
target_link_libraries(hello_mpi PUBLIC ${MPI_Fortran_LIBRARIES})
I would like to be able to (i) get rid of the warning/message and more importantly (ii) enable suggestions from MPI when I press CTRL+space as it would if I was calling from an internal module.
I'll post a partial answer since it's better than nothing, hopefully this helps someone else and/or enables someone else to answer my question fully.
It seems the issue relates to the Fortran language server, which can be configured by adding a .fortls JSON file, as explained on its Github README: https://github.com/hansec/fortran-language-server
I added the following, which allowed it to find not only local modules but also MPI (and the external module json-fortran):
{
"source_dirs": ["src", "."],
"ext_source_dirs": [
"/path/to/json-fortran/src",
"/path/to/openmpi-4.1.2/ompi/mpi/fortran/use-mpi-f08",
]
}
This doesn't capture all functions in json-fortran, which I think is because of its .inc files, as it doesn't give me function pointers like json_file::get at autocomplete.
As for MPI, this kind of works, as it gives me all the functions I can think of needing, but with _f08 appended to the end of it. I don't know the inner workings of OpenMPI but I guess e.g. MPI_Init wraps MPI_Init_f08 for reasons of backward compatibility. For now I can simply autocomplete to the _f08 version and remove that bit manually. (I also tried adding openmpi-4.1.2/ompi/mpi/fortran/use-mpi-tkr and openmpi-4.1.2/ompi/mpi/fortran/mpif.h but no luck).
Would be nice to get this detail sorted though. It is also mildly annoying that I must manually include the source dirs now (removing it makes it not find local modules).
I'm using XS to create a Perl Module which uses a C library.
For testing purposes, I've created a test library which has two simple functions:
void kzA() (does a simple printf)
void kzB(int i, char *str) (does a printf of the received parameters)
I've also created some glue in XS, in order, for now, to access the kzA() function:
(I'm only showing the function itself, but the includes are there, too, in the XS)
void
ka()
CODE:
printf("Before kzA()\n");
kzA();
printf("After kzA()\n");
So, I compiled the test library as fc.so, and it is in the same directory as my xs file, and my Makefile.PL (/workspace/LirePivots)
In my Makefile.PL, I set the LIBS key to ['-L/workspace/LirePivots -l:fc.so'], but when executing it with perl (perl Makefile.PL), it says "Warning (mostly harmless): No library found for -l:fc.so"
It then writes a Makefile which does NOT mention said library. And then, after compiling (with "make") and installing (with "sudo make install"), when I run my test script which calls the ka() function from my module, I get the line "before", but the kzA() function isn't called, obviously, because it cannot find the kzA symbol, and the program stops there.
Creating a C test program which I would link with the very same arguments (-l:fc.so -L/workspace/LirePivots) does work, and, as long as I put the path in LD_LIBRARY_PATH, it finds the function and runs it correctly.
I also tried renaming the library libfc.so, and changing the -l part to "-lfc", but it didn't work either. It never manages to find the library.
Does anyone know what I do wrong ?
EDIT:
As requested, I created a minimum example: https://github.com/kzwix/xsTest
To run it, you'll need to have a Linux with Perl 5, along with XS (package perl-devel, on Redhat). And a C compiler, and make, obviously.
Ok, I still don't know the reason why it wouldn't find the library. But I found a workaround:
By adding the test library as "libfc.so" to /usr/lib, then running "sudo ldconfig", the library got added to the cache (when named fc.so, even if in /usr/lib, ldconfig would not add it. Also, it wouldn't work with symbolic links, either, I had to really copy it there).
After the library got added to the cache, "perl Makefile.PL" would still not find the library. I had to use "-L/usr/lib" in addition to "-lfc" for it to at long last find the library, and "agree" to add the parameters to the link step of the library.
After this happened, I could compile with "make", and executing the test program did work as originally intended (I saw both the "before" and "after" printf, and I saw the one from the function in the kzA() function from libfc.so)
Thanks Håkon Hægland for helping.
(I can't provide the Dockerfiles, they link to images internal to my organization, which I'm not allowed to share)
I would like to import an existing C code (or any other text) into my generated code by Matlab simulink.I have some tasks that made in C,but in the future i want to develop in matlab.I work in simulink,and I can compile the models,but I want to use some special function what I previously wrote in C (because of pointer etc.).
The problem is that I don't know how to put in these texts into the model,and after the code generation these texts stay in the original format,and placed in the expected line.
And what I would like:
You can achieve this using the S-Function Builder. It allows one to create C code blocks, which get compiled with the model run. If using Code Generator, it gets inserted into generated code.
I generally use it to call functions from my external code or libraries, as in some Raspberry Pi Driver blocks I created.
It generates .c, .h and .mex files for each block and is quite clunky but does work!
BTW: If it's just to use an external pointer, you can happily use ImportedPointer/ExportedPointer for this. I find this handy for variables between generated code and container.
I'm learning Elixir and attempting to use the elixir-mongo library. During the auth/1 command, A the function uses Server.call, piping in the MongoDB request string. looking at the Mongo.Server class, it does not appear to be an actual genserver, nor have a method to match call/1. How is this working?
With high probability it doesn't work. Mongo.Server module doesn't export call function. There are no macros that generate it magically. My guess is that master branch is currently broken. If you are using the library and want to dig into the sources make sure you are looking at the same tag as the version you are using in your project.
Also, there are no classes and methods in Elixir. There are modules and functions :)
I come with the background in languages like Java or Python where modular programming is enabled by packaging system and import directive (aka namespace aliasing). Historically MATLAB's approach to resolve problems like naming conflicts boils down to setting/playing with MATLABPATH, renaming/extending identifiers with prefixes, etc. So far I have been successfully playing with native MATLAB packaging by prepending plus sign "+" before the folder name (MATLAB notation for package also see here). Obviously they are very long to type ;-) Basically I am back to the similar problem as discussed here with no solution. So let me paraphrased for my particular angle:
Assume I have folder +mypackage defined containing file myfun.m with the function code of the same name.
How to achieve aliasing for MATLAB function inside the user (non-java) package as illustrated by the following python code:
from mypackage import myfun
?
[EDIT] Please note that AFAIK import keyword works only for java classes (with jvm attached to MATLAB process). No, import is working perfectly fine for both functions and aliases for objects and function of both Java and MATLAB origin.
Possibly related but not the same.
[EDIT2]
python's
from mypackage import myfun as anotherfun
is equivalent to MATLAB's
anotherfun = #mypackage.myfun
Doesn't
import mypackage.myfun
work?
link to documentation