PHP (Hypertext Preprocessor), SQL ( , , ), JavaScript (- ).
, PHP, . PHP . , , .
:
1. html .
2. .
3. PHP /SQL .
4. .
5. .
.
1) , , - . , html-. , , .
2) , . JavaScript AJAX( JavaScript XML -, -).
3) . - (, ).
4) . . PHP -.
5) .
. .
, , , .
, , , . TF-IDF. ( , (MSDN).
TF-IDF
Gerard Salton ( Karen Sparck Jones).TF-IDF ( . TF term frequency, IDF inverse document frequency) , , . , .
|
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TF (term frequency) . , .
TF =
, .
IDF (inverse document frequency) , . IDF .
IDF = ,
|D| ;
, ( ).
, TF-IDF : TF IDF.
TF-IDF .
100 2 , (TF) 0,02 (2/100). (DF) , . , 100 10 000 , (DF) 0,01 (100/10000). TF DF ( IDF). , TF-IDF 2 (0,02/0,01).
TF-IDF , ( ) . (VSM) , ( , , , .), . . .
1. http://wikipedia.org.
2. . PHP . .: -, 2007. 346 .
References
1. http://wikipedia.org.
2. Steven Holzner. Spiring into PHP 5.