What is significance of comma (,) in .x file - directx

I am loading and writing DirectX .x file. I am trying to follow a third party application in the way it loads the file.
If I have following mesh:
Mesh obj1 {
4;
6.500000;-3.656250;0.000000;,
-6.500000;3.656250;0.000000;,
-6.500000;-3.656250;0.000000;,
6.500000;3.656250;0.000000;;
In this, even if I remove the commas and write everything in one line, the third party tool is still able to load the file.
I couldn't find a proper documentation that describes role of comma. It is quite possible that only this tool is loading it this way. Can you please inform me about the role of comma in .x file (particularly in Mesh).
Thanks!

Commas are used to separate array members. For brief description follow the link http://paulbourke.net/dataformats/directx/#xfilefrm_Use_of_commas

Related

ID3 Parser and Editor

I'm writing an ID3 parser and editor. It does already support ID3v1, v2.1-2.3. Are there any other widely used ID3 versions or extensions? For example, I've read about Enhanced ID3v1 tag (which goes before ID3v1) and starts with "TAG+", but I've never seen it inside MP3 files. Should I implement support for it anyway?
"ID3v2.1" never existed.
Yes, Enhanced TAG identifies by TAG+, which extends IDv1.
For a list of all metadata systems to be expected in MP3 files see https://stackoverflow.com/a/62366354 - top priority should have ID3v2.4 as you will encounter those most aside from ID3v2.3. Then go for informal and/or legacy ones because those can still be encountered (just because files become old doesn't mean they cease to exist).
Keep the following things in mind when parsing files:
A file can have both: IDv1 and IDv2 tags.
A file can have multiple IDv2 tags (i.e. IDv2.3 and IDv2.4). Although it shouldn't occur it should pose no problem to your parser to also accept multiple tags of the same version.
ID3v2 is not limited to MP3 files (but IDv1 and all its informal extensions are).
Consider the following parsing order in an MP3 file:
Check for ID3v1 at the end of the file.
Check for ID3v1.2 in front of ID3v1.
Check for Enhanced TAG in front of ID3v1.
Check for multiple ID3v2 at the start of file and, as for ID3v2.4, a footer at the end of the file in front of all ID3v1-like tags.

What is the recommended way to make & load a library?

I want to make a small "library" to be used by my future maxima scripts, but I am not quite sure on how to proceed (I use wxMaxima). Maxima's documentation covers the save(), load() and loadFile() functions, yet does not provide examples. Therefore, I am not sure whether I am using the proper/best way or not. My current solution, which is based on this post, stores my library in the *.lisp format.
As a simple example, let's say that my library defines the cosSin(x) function. I open a new session and define this function as
(%i0) cosSin(x) := cos(x) * sin(x);
I then save it to a lisp file located in the /tmp/ directory.
(%i1) save("/tmp/lib.lisp");
I then open a new instance of maxima and load the library
(%i0) loadfile("/tmp/lib.lisp");
The cosSin(x) is now defined and can be called
(%i1) cosSin(%pi/4)
(%o1) 1/2
However, I noticed that a substantial number of the libraries shipped with maxima are of *.mac format: the /usr/share/maxima/5.37.2/share/ directory contains 428 *.mac files and 516 *.lisp files. Is it a better format? How would I generate such files?
More generally, what are the different ways a library can be saved and loaded? What is the recommended approach?
Usually people put the functions they need in a file name something.mac and then load("something.mac"); loads the functions into Maxima.
A file can contain any number of functions. A file can load other files, so if you have somethingA.mac and somethingB.mac, then you can have another file that just says load("somethingA.mac"); load("somethingB.mac");.
One can also create Lisp files and load them too, but it is not required to write functions in Lisp.
Unless you are specifically interested in writing Lisp functions, my advice is to write your functions in the Maxima language and put them in a file, using an ordinary text editor. Also, I recommend that you don't use save to save the functions to a file as Lisp code; just type the functions into a file, as Maxima code, with a plain text editor.
Take a look at the files in share to get a feeling for how other people have gone about it. I am looking right now at share/contrib/ggf.mac and I see it has a lengthy comment header describing its purpose -- such comments are always a good idea.
For principiants, like me,
Menu Edit:configure:Startup commands
Copy all the functions you have verified in the first box (this will write your wxmaxima-init.mac in the location indicated below)
Restart Wxmaxima.
Now you can access the functions whitout any load() command

Using signature file in script

I like using .fsi signature files to control visibility. However, if I have both Foo.fsi and Foo.fs files in my solution, and #load "Foo.fs" in a script, it doesn't seem like the corresponding signature file gets used. If I do:
#load "Foo.fsi"
#load "Foo.fs"
... then the desired visibility control happens. Is this the recommended way to achieve this, or is there a better way to do it? In a perfect world, one would like to see the signature file automatically loaded, too.
Not a final answer, but a better way.
From reading Expert F# 4.0 one can do
#load "Foo.fsi" "Foo.fs" "Foo.fsx"
All three loads are on one line.
TL;DR
The link to the book is via WolrdCat just put in a zip code and it will show you locations near there where the book can be found.

Options for MeCab Japanese tokenizer on iOS?

I'm using the iPhone library for MeCab found at https://github.com/FLCLjp/iPhone-libmecab . I'm having some trouble getting it to tokenize all possible words. Specifically, I cannot tokenize "吉本興業" into two pieces "吉本" and "興業". Are there any options that I could use to fix this? The iPhone library does not expose anything, but it uses C++ underneath the objective-c wrapper. I assume there must be some sort of setting I could change to give more fine-grained control, but I have no idea where to start.
By the way, if anyone wants to tag this 'mecab' that would probably be appropriate. I'm not allowed to create new tags yet.
UPDATE: The iOS library is calling mecab_sparse_tonode2() defined in libmecab.cpp. If anyone could point me to some English documentation on that file it might be enough.
There is nothing iOS-specific in this. The dictionary you are using with mecab (probably ipadic) contains an entry for the company name 吉本興業. Although both parts of the name are listed as separate nouns as well, mecab has a strong preference to tag the compound name as one word.
Mecab lacks a feature that allows the user to choose whether or not compounds should be split into parts. Note that such a feature is generally hard to implement because not everyone agrees on which compounds can be split and which ones can't. E.g. is 容疑者 a compound made up of 容疑 and 者? From a purely morphological point of view perhaps yes, but for most practical applications probably no.
If you have a list of compounds you'd like to get segmented, a quick fix is to create a user dictionary for the parts they consist of, and make mecab use this in addition to the main dictionary.
There is Japanese documentation on how to do this here. For your particular example, it would involve the steps below.
Make a user dictionary with two entries, one for 吉本 and one for 興業:
吉本,,,100,名詞,固有名詞,人名,名,*,*,よしもと,ヨシモト,ヨシモト
興業,,,100,名詞,一般,*,*,*,*,こうぎょう,コウギョウ,コウギョウ
I suspect that both entries exist in the default dictionary already, but by adding them to a user dictionary and specifying a relatively low specificness indicator (I've used 100 for both -- the lower, the more likely to be split), you can get mecab to tend to prefer the parts over the whole.
Compile the user dictionary:
$> $MECAB/libexec/mecab/mecab-dict-index -d /usr/lib64/mecab/dic/ipadic -u mydic.dic -f utf-8 -t utf-8 ./mydic
You may have to adjust the command. The above assumes:
Mecab was installed from source in $MECAB. If you use mecab installed by a package manager, you might have difficulties finding the mecab-dict-index tool. Best install from source.
The default dictionary is in /usr/lib64/mecab/dict/ipadic. This is not part of the mecab package; it comes as a separate package (e.g. this) and you may have difficulties finding this, too.
mydic is the name of the user dictionary created in step 1. mydic.dic is the name of the compiled dictionary you'll get as output (needs not exist).
Both the system dictionary (-t option) and the user dictionary (-f option) are encoded in UTF-8. This may be wrong, in which case you'll get an error message later when you use mecab.
Modify the mecab configuration. In a system-wide installation, this is a file named /usr/lib64/mecab/dic/ipadic/dicrc or similar. In your case it may be located somewhere else. Add the following line to the end of the configuration file:
userdic = home/myhome/mydic.dic
Make sure the absolute path to the dictionary compiled above is correct.
If you then run mecab against your input, it will split the compound into its parts (I tested it, using mecab 0.994 on a Linux system).
A more thorough fix would be to get the source of the default dictionary and manually remove all compoun nouns you want to get split, then recompile the dictionary. As a general remark, using a CJK tokenizer for a serious application in production mode over a longer period of time usually involves a certain amount of dictionary maintenance (adding/removing entries) regularly.

What are the rules for file extensions in Windows and Unix?

i'm currently using File::Basename fileparse to separate out a file's directory, base file name and it's extension using something like this:
my($myfile_name,$mydirectory, $file_extension) = fileparse($$rhash_params{'storage_full_path_location'},'\..{1,4}');
But see that there's a variation where you can actually provide a array of suffixes to the function, the array would contains all the known file extension.
So i'm trying to find a safe way to do this as i've seen that i've got some strange file names to process, i.e. file.0f1.htm, etc.
Question:
Is there a list of commonly used
extension for Windows and Unix
systems? But in my case it's mainly
for Windows.
And is it safe to
assume that all file names in
Windows should have an extension
ending with three letter characters?
And if there's an even better way to do this, please share.
Thanks.
Updates:
So obviously i must be drunk to forgot about those other extension. :)
Thus i've updated the current regex to allow from 1-4chars.
In this case, how should i change my regex line to properly match it?
Or is it an even better idea to look for all those commonly used extension from google and put them into an array to be passed to the function instead? My users are usually either students or teachers.
1. Is there a list of commonly used extension for Windows and Unix
systems? But in my case it's mainly
for Windows.
Yes, loads, all over the internet: http://www.google.com/search?q=common+file+extensions
2. And is it safe to assume that all file names in Windows should have
an extension ending with three letter
characters?
No, it's perfectly possible to use '.c', '.java', etc in Windows.
There are several fault assumptions in your code:
files need not have extensions. For example most binary executables on Unix/Linux/... don't have an extension at all. They are simply calls "bash", "wget", "sed", "Xorg", ...
extensions need not be three characters long, as #Alnitak already told you: ".c", ".java", ".mpeg", ".jpeg", ".html" are all perfectly fine and rather wide-spread extensions
cutting at the last "." is probably saver, but can still fail for files with no extensions or with multiple (or multi-part) extensions such as ".tar.gz", "tar.bz2", which occur rather often in the Unix/Linux/...-World

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