Is it possible to get the operating system in maxima? I have some code that needs the unix / or windows \ for path names. How can I find out which operating system the code is running in?
To give some context, I have the following code:
windows: false$
divider: "/"$
if (windows) then divider: "\\"$
initfile: concat(maxima_userdir, divider, "maxima-init.mac");
load(operatingsystem)$
dir: getcurrentdirectory();
if (substring(dir, slength(dir)) # divider) then dir: concat(dir, divider)$
repo: concat(dir, "$$$.mac")$
live: concat(dir, "live_packages", divider, "$$$.mac")$
with_stdout(initfile, printf(true, ""))$
with_stdout(initfile, printf(true, concat("file_search_maxima: append (file_search_maxima, [
~s,
~s
]);"), repo, live))$
Take a look at the output of build_info, specifically the field host (i.e. foo#host where foo : build_info()). See ? build_info for more information.
On my (Linux) system I get: x86_64-unknown-linux-gnu I think on MS Windows you'll get a string containing windows or at least win or maybe win32.
There may be other ways to figure out the system type so let me know if that doesn't work for you. Also it is possible that there is a global variable floating around which tells the path separator; I would have to look for that.
If you're not adverse to writing a little bit of Lisp code, another approach is to use the file and directory functions in Common Lisp, which are more extensive than in Maxima. See the section on filenames in the Common Lisp Hyperspec. I think maybe MERGE-PATHNAMES and/or MAKE-PATHNAME might be relevant.
Related
I'm trying to write a simple machine learning application in Ada, and also trying to find a good framework to use. My knowledge of one thing is extremely minimal, and of the other is somewhat minimal.
There are several nifty machine learning frameworks out there, and I'd like to leverage one for use with an Ada program, but I guess I'm just...at a loss. Can I use an existing framework written in Python, for instance and wrap (or I guess, bind?) the API calls in Ada? Should I just pass off the scripting capabilities? I'm trying to figure it out.
Case in point: Scikit (sklearn)
https://scikit-learn.org/stable/tutorial/text_analytics/working_with_text_data.html#
This does some neat stuff, and I'd like to be able to leverage this, but with an Ada program. Does anyone have advice from a similar experience?
I am just researching, so I have tried finding information.
http://www.inspirel.com/articles/Ada_Python_Binding.html
https://scikit-learn.org/stable/tutorial/text_analytics/working_with_text_data.html#
The inspirel solution is based on python2.7. If you're using anything from python3.5 onwards a few mods need to be made. On Linux, changing to say python 3.7, you'd just change
--for Default_Switches ("Ada") use ("-lpython2.7");
for Default_Switches ("Ada") use ("-lpython3.7");
but on windows, the libraries aren't dumped in a community lib so gnat doesn't know where to find them. All the packages are kept separately. The -L has to be added to tell the linker where to find the library. Alternatively, you can use for lib_dir. In my case, I did a non-admin install of python, so it looks something like
for Default_Switches ("Ada") use ("-L\Users\StdUser\AppData\Local\Programs\Python\Python37-32\libs", "-lpython37");
Note that on windows, the library is called python37: not python3.7. Use gprbuild instead of gnatmake -p, which has been deprecated. If you do all your mods correctly
gprbuild ada_main.gpr
should give you an executable in obj\ada_main.exe if it builds. If a later version of python is used, some edits need to be made
python_module.py
#print 'Hello from Python module'
print('Hello from Python module')
#print 'Python adding:', a, '+', b
print('Python adding:', a, '+', b)
ada_main.adb
-- Python.Execute_String("print 'Hello from Python!'");
Python.Execute_String("print('Hello from Python!')");
Some routines have been deprecated so the linkage has to change
python.adb
--pragma Import(C, PyInt_AsLong, "PyInt_AsLong");
pragma Import(C, PyInt_AsLong, "PyLong_AsLong");
--pragma Import(C, PyString_FromString, PyString_FromString");
pragma Import(C, PyString_FromString, "PyUnicode_FromString");
Running the build and executable should give
C:\Users\StdUser\My Documents\ada-python>gprbuild ada_main.gpr
Compile
[Ada] ada_main.adb
Bind
[gprbind] ada_main.bexch
[Ada] ada_main.ali
Link
[link] ada_main.adb
C:\Users\StdUser\My Documents\ada-python>obj\ada_main.exe
executing Python directly from Ada:
Hello from Python!
loading external Python module and calling functions from that module:
Hello from Python module!
asking Python to add two integers:
Python adding: 10 + 2
Ada got result from Python: 12
we can try other operations, too:
subtract: 8
multiply: 20
divide : 5
Remember to put the pythonxx.dll somewhere on your path otherwise it won't be able to find the library when it starts executing.
The major operating systems seem to have a designated place to store configuration files.
On Linux it would be something like $HOME/.myprogram/data or $HOME/.config/myprogram/data, or perhaps a better practice would be to read $XDG_CONFIG_HOME.
On macOS it would be $HOME/.myprogram/data or $HOME/Library/Preferences/myprogram/data.
On Windows it would be %appdata%/myprogram/data.
How to get such value in a portable manner in Lua?
Check the existence condition of a variable with...
if (os.getenv('XDG_CONFIG_HOME')) then
os.execute('ls ' .. os.getenv('XDG_CONFIG_HOME'))
else -- Or: elseif (nextcondition) then
print('XDG_CONFIG_HOME', 'Not exists')
-- Maybe next check here?
end
But be aware that a user could start Lua with only that environment that Lua needs.
Like...
lua ()
{
env -i DISPLAY=:0 LANG='de_DE.UTF-8' TERM='xterm-256color' LUA_PATH='./lua/?.lua' LUA_CPATH='./lua/?.so' /usr/local/bin/lua "${#}"
}
Then check for XDG_CONFIG_HOME will allways fail.
Because above environment knows nothing about HOME, USER and XDG_CONFIG_HOME.
PS: I know a place too where my linux system saves configs/savegames or whatever
${HOME}/.local/share/
I am using Verilator to incorporate an algorithm written in SystemVerilog into an executable utility that manipulates I/O streams passed via stdin and stdout. Unfortunately, when I use the SystemVerilog $display() function, the output goes to stdout. I would like it to go to stderr so that stdout remains uncontaminated for my other purposes.
How can I make this happen?
Thanks to #toolic for pointing out the existence of $fdisplay(), which can be used thusly...
$fdisplay(STDERR,"hello world"); // also supports formatted arguments
IEEE Std 1800-2012 states that STDERR should be pre-opened, but it did not seem to be known to Verilator. A workaround for this is:
integer STDERR = 32'h8000_0002;
Alternatively, you can create a log file handle for use with $fdisplay() like so...
integer logfile;
initial begin
$system("echo 'initial at ['$(date)']'>>temp.log");
logfile = $fopen("temp.log","a"); // or open with "w" to start fresh
end
It might be nice if you could create a custom wrapper that works like $display but uses your selected file descriptor (without specifying it every time). Unfortunately, that doesn't seem to be possible within the language itself -- but maybe you can do it with the DPI, see DPI Display Functions (I haven't gotten this to work so far).
If I execute a binary in a clearcase view, and look at /proc/self/exe for that on Linux, I see something like the following:
$ cd /proc/19220
$ ls -l exe
lrwxrwxrwx 1 peeterj pdxdb2 0 2012-11-30 13:04 exe -> /home/peeterj/views/peeterj_clang-7.vws/.s/00024/8000028250b8f1d1llvm-config
The clang llvm-config program, not unreasonably, uses this output to try to figure out the absolute fully qualified path that it is located in (I assume in case argv[0] isn't fully qualified).
Is there a way to find the location within the view that this corresponds to. For example, in this case, the llvm-config exe is actually in:
/vbs/bldsupp/linuxamd64/clang/debug/bin
(I'm wondering if it's feasible to modify clang's GetExecutablePath() function to figure this out.)
No trivial solution here (for an old version of ClearCase though):
The technote "PK27447: WITHIN A CLEARCASE DYNAMIC VIEW, THE READLINK() CALL ON LINUX RETURNS THE WRONG PATH FOR THE EXECUTABLE'S /PROC/SELF/EXE VALUE" suggests:
Local fix
Use getcwd(), get_current_dir_name(), getwd() in applications slated for a VOB/View context
Create an interposer library to intercept the readlink() call, and modify to use any of the above calls to return the proper data
The cause:
/proc/self/exe returns the improper path while getcwd succeeds.
Unfortunately, for /proc/self/exe to return the proper value [from within a VOB/View context] would require a change within the Linux kernel to allow MVFS to "override" the present setting.
IBM LTC has been working on having the Linux community adopt this change so that we can then incorporate the new features within MVFS.
Related: Bug Sun 6189256.
I am porting a C# program to Linux (using Mono). The only compatibility issues that MoMA has found were all related to printing: P/Invokes of functions from winspool.drv:
ClosePrinter
EndDocPrinter
EndPagePrinter
OpenPrinter
StartDocPrinter
StartPagePrinter
WritePrinter
These are all used in the same class, which prints files (which must be either PDF or PS) by wrapping them in PJL (to set the paper size/tray/orientation) and calling WritePrinter.
I'll need to rewrite this printing logic with non-Windows-specific code. A previous question refers to System.Drawing.Printing, but it seems to be way too low level. I don't want DrawString and DrawImage, I want "print this PostScript file". Is there functionality in Mono to do this?
I ended up using System.Diagnostics.Process to call the lp command.