I have the following test code trying to read file into a list
open('raw250-split1.pl', read, Stream),
read(Stream,train_xs(TrainXs)),
length(TrainXs, MaxTrain).
I will omit part of the output due to the file is quite large.
It works well with yap,
➜ chill git:(master) ✗ yap [18/06/19| 5:48PM]
% Restoring file /usr/lib/Yap/startup.yss
YAP 6.2.2 (x86_64-linux): Sat Sep 17 13:59:03 UTC 2016
?- open('raw250-split1.pl', read, Stream),
read(Stream, train_xs(TrainXs)),
length(TrainXs, MaxTrain).
MaxTrain = 225,
Stream = '$stream'(3),
TrainXs = [[parse([which,rivers,run,through,states,bordering,new,mexico,/],answer(_A,(river(_A),traverse(_A,_B),next_to(_B,_C),const(_C,stateid('new mexico')))))],
<omited output>
,[parse([what,is,the,largest,state,capital,in,population,?],answer(_ST,largest(_SU,(capital(_ST),population(_ST,_SU)))))]]
But on swi-prolog, it will produce Type error
➜ chill git:(master) ✗ swipl [18/06/19| 7:24PM]
Welcome to SWI-Prolog (threaded, 64 bits, version 7.6.4)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.
For online help and background, visit http://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).
?- open('raw250-split1.pl', read, Stream),
read(Stream, train_xs(TrainXs)),
length(TrainXs, MaxTrain).
ERROR: raw250-split1.pl:4:
Type error: `list' expected, found `parse(which.(rivers.(run.(through.(states.(bordering.(new.(mexico.((/).[])))))))),
<omited output>
,answer(_67604,(state(_67604),next_to(_67604,_67628),const(_67628,stateid(kentucky))))).[].(parse(what.((is).(the.(largest.(state.(capital.(in.(population.((?).[])))))))),answer(_67714,largest(_67720,(capital(_67714),population(_67714,_67720))))).[].[]))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))' (a compound)
In:
[10] throw(error(type_error(list,...),context(...,_67800)))
[7] <user>
Note: some frames are missing due to last-call optimization.
Re-run your program in debug mode (:- debug.) to get more detail.
What might be the problem for the error here?
File raw250-split1.pl can be found from the ftp url below, if you'd like to try it.
Thank you for the help!
I am trying to migrate an earlier code to SWI-Prolog, which was written in
SICStus 3 #3: Thu Sep 12 09:54:27 CDT 1996 or earlier
by Raymond J. Mooney ftp://ftp.cs.utexas.edu/pub/mooney/chill/.
All the questions with this tag are all related to this task. I'm new to prolog, helps and suggestions are welcomed!
The raw250-split1.pl was apparently written using canonical notation. The traditional list functor is ./2 but SWI-Prolog 7.x changed it to '[|]'/2 in order to use ./2 for other purposes. This results in the the variable TrainXs being instantiated by the read/2 call to a compound term whose argument is not a list:
?- open('raw250-split1.pl', read, Stream), read(Stream,train_xs(TrainXs)).
Stream = <stream>(0x7f8975e08e90),
TrainXs = parse(which.(rivers.(run.(through.(states.(bordering.(... . ...)))))), answer(_94, (river(_94), traverse(_94, _100), next_to(_100, _106), const(_106, stateid('new mexico'))))).[].(parse(what.((is).(the.(highest.(point.(... . ...))))), answer(_206, (high_point(_204, _206), const(_204, stateid(montana))))).[].(parse(what.((is).(the.(most.(... . ...)))), answer(_298, largest(_300, (population(_298, _300), state(...), ..., ...)))).[].(parse(through.(which.(states.(... . ...))), answer(_414, (state(_414), const(..., ...), traverse(..., ...)))).[].(parse(what.((is).(... . ...)), answer(_500, longest(_500, river(...)))).[].(parse(how.(... . ...), answer(_566, (..., ...))).[].(parse(... . ..., answer(..., ...)).[].(parse(..., ...).[].(... . ... .(... . ...))))))))).
YAP still uses the ./2 functor for lists, which explains why it can handle it. A workaround for SWI-Prolog is to start it with the --traditional command-line option:
$ swipl --traditional
...
?- open('raw250-split1.pl', read, Stream), read(Stream,train_xs(TrainXs)).
Stream = <stream>(0x7faeb2f77700),
TrainXs = [[parse([which, rivers, run, through, states, bordering|...], answer(_94, (river(_94), traverse(_94, _100), next_to(_100, _106), const(_106, stateid('new mexico')))))], [parse([what, is, the, highest, point|...], answer(_206, (high_point(_204, _206), const(_204, stateid(montana)))))], [parse([what, is, the, most|...], answer(_298, largest(_300, (population(_298, _300), state(...), ..., ...))))], [parse([through, which, states|...], answer(_414, (state(_414), const(..., ...), traverse(..., ...))))], [parse([what, is|...], answer(_500, longest(_500, river(...))))], [parse([how|...], answer(_566, (..., ...)))], [parse([...|...], answer(..., ...))], [parse(..., ...)], [...]|...].
The type error you get is due to the length/2 expecting a list when the first argument is bound.
There is a tilde as last character in that file, causing the syntax being invalid, so you should remove it before reading. I don't know why YAP accept the file as valid, should raise an error AFAIK.
There is a read option dotlists/2 in SWI-Prolog:
dotlists(Bool)
If true (default false), read .(a,[]) as a
list, even if lists are internally nor constructed
using the dot as functor. This is primarily intended
to read the output from write_canonical/1 from
other Prolog systems. See section 5.1.
http://www.swi-prolog.org/pldoc/man?predicate=read_term/2
This gives you the desired result, without changing the mode:
Welcome to SWI-Prolog (threaded, 64 bits, version 8.1.0)
?- read_term(X, [dotlists(true)]).
|: .(a,.(b,.(c,[]))).
X = [a, b, c].
I want to try the LDA -c code by Blie .et.al. as it is in this link.
I have compiled the code, and when I run ./lda in my terminal, the following result is displayed.
usage : lda est [initial alpha] [k] [settings] [data] [random/seeded/manual=filename/*] [directory]
lda inf [settings] [model] [data] [name]
Which means that, it has been complied correctly.
However, in spite reading the README.txt file there, I am not being able to succesfully run the LDA code.
Either it says Segmentation fault (core dumped) or killed.
What am I missing? How to use it on the example data they have given?
I have read the stack overflow answer to the question asked here, but it was not useful as I dont know the default values.
P.S: I am a beginer.
Are you using ap.txt instead of ap.dat by any chance? lda-c doesn't take raw sentences or marked up data as input; it takes a sequence of bag of words information for each document. When ap.dat has a line like
186 0:1 6144:1 3586:2 ..., it means that the corresponding document has 186 distinct words, word 0 appears once, word 6144 appears once, word 3586 appears twice, and so on.
This command works for me (using Blei's original code):
./lda est 0.1 10 settings.txt ap.dat random modeldir
(Feel free to tweak the initial alpha (0.1) and number of topics (10) as you wish.)
How can I, in C, output a value from a syscall to the Linux console so that it will be visible after a dmesg? What method do I use for printing?
You're looking for the printk() function; some documentation on the types that it supports is found in Documentation/printk-formats.txt. It is defined in kernel/printk.c.
I assume you mean in the user-space. You can write the string to /dev/kmsg. In shell, just echo it. In C, it would be also very easy.
[root#cr0 ~]# echo hello > /dev/kmsg
[root#cr0 ~]# dmesg | tail -1
[24156.408735] hello
But if you mean in kernel space, of course, you need to call printk().
In addition, you might be interested (even if that does not answer exactly your question), by the openlog & syslog functions. From within an application, they are the proper way to get system logging.
Is it possible that I can view the line number and file name (for my program running with ltrace/strace) along with the library call/system call information.
Eg:
code section :: ptr = malloc(sizeof(int)*5); (file:code.c, line:21)
ltrace or any other tool: malloc(20) :: code.c::21
I have tried all the options of ltrace/strace but cannot figure out a way to get this info.
If not possible through ltrace/strace, do we have any parallel tool option for GNU/Linux?
You may be able to use the -i option (to output the instruction pointer at the time of the call) in strace and ltrace, combined with addr2line to resolve the calls to lines of code.
No It's not possible. Why don't you use gdb for this purpose?
When you are compiling application with gcc use -ggdb flags to get debugger info into your program and then run your program with gdb or equivalent frontend (ddd or similar)
Here is quick gdb manual to help you out a bit.
http://www.cs.cmu.edu/~gilpin/tutorial/
You can use strace-plus that can collects stack traces associated with each system call.
http://code.google.com/p/strace-plus/
Pretty old question, but I found a way to accomplish what OP wanted:
First use strace with -k option, which will generate a stack trace like this:
openat(AT_FDCWD, NULL, O_RDONLY) = -1 EFAULT (Bad address)
> /usr/lib/libc-2.33.so(__open64+0x5b) [0xefeab]
> /usr/lib/libc-2.33.so(_IO_file_open+0x26) [0x816f6]
> /usr/lib/libc-2.33.so(_IO_file_fopen+0x10a) [0x818ca]
> /usr/lib/libc-2.33.so(__fopen_internal+0x7d) [0x7527d]
> /mnt/r/build/tests/main(main+0x90) [0x1330]
> /usr/lib/libc-2.33.so(__libc_start_main+0xd5) [0x27b25]
> /mnt/r/build/tests/main(_start+0x2e) [0x114e]
The address of each function call are displayed at the end of each line, and you can paste it to addr2line to retrieve the file and line. For example, we want to locate the call in main() (fifth line of the stack trace).
addr2line -e tests/main 0x1330
It will show something like this:
/mnt/r/main.c:55
I was searching online for something to help me do assembly line profiling. I searched and found something on http://www.webservertalk.com/message897404.html
There are two parts of to this problem; finding all instructions of a particular type (inc, add, shl, etc) to determine groupings and then figuring out which are getting executed and summing correcty. The first bit is tricky unless grouping by disassembler is sufficient. For figuring which instructions are being executed, Dtrace is of course your friend here( at least in userland).
The nicest way of doing this would be instrument only the begining of each basic block; finding these would be a manual process right now... however, instrumenting each instruction is feasible for small applications. Here's an example:
First, our quite trivial C program under test:
main()
{
int i;
for (i = 0; i < 100; i++)
getpid();
}
Now, our slightly tricky D script:
#pragma D option quiet
pid$target:a.out::entry
/address[probefunc] == 0/
{
address[probefunc]=uregs[R_PC];
}
pid$target:a.out::
/address[probefunc] != 0/
{
#a[probefunc,(uregs[R_PC]-address[probefunc]), uregs[R_PC]]=count();
}
END
{
printa("%s+%#x:\t%d\t%#d\n", #a);
}
main+0x1: 1
main+0x3: 1
main+0x6: 1
main+0x9: 1
main+0xe: 1
main+0x11: 1
main+0x14: 1
main+0x17: 1
main+0x1a: 1
main+0x1c: 1
main+0x23: 101
main+0x27: 101
main+0x29: 100
main+0x2e: 100
main+0x31: 100
main+0x33: 100
main+0x35: 1
main+0x36: 1
main+0x37: 1
From the example given, this is exactly what i need. However I have no idea what it is doing, how to save the DTrace program, how to execute with the code that i want to get the results of. So i opened this hoping some people with good DTrace background could help me understand the code, save it, run it and hopefully get the results shown.
If all you want to do is run this particular DTrace script, simply save it to a .d script file and use a command like the following to run it against your compiled executable:
sudo dtrace -s dtracescript.d -c [Path to executable]
where you replace dtracescript.d with your script file name.
This assumes that you have DTrace as part of your system (I'm running Mac OS X, which has had it since Leopard).
If you're curious about how this works, I wrote a two-part tutorial on using DTrace for MacResearch a while ago, which can be found here and here.