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<H1><A href="http://www.csie.ntu.edu.tw/~cjlin/libsvm">LIBSVM</A> FAQ
</H1></B></A><B>last modified : </B>Thu, 18 Sep 2008 14:35:56 GMT
<CLASS="CATEGORIES">
<LI><A href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#_TOP">All
Questions</A>(69)
<UL><B>
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q1:_Some_sample_uses_of_libsvm">Q1:_Some_sample_uses_of_libsvm</A>(2)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q2:_Installation_and_running_the_program">Q2:_Installation_and_running_the_program</A>(9)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q3:_Data_preparation">Q3:_Data_preparation</A>(6)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q4:_Training_and_prediction">Q4:_Training_and_prediction</A>(32)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q5:_Probability_outputs">Q5:_Probability_outputs</A>(3)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q6:_Graphic_interface">Q6:_Graphic_interface</A>(3)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q7:_Java_version_of_libsvm">Q7:_Java_version_of_libsvm</A>(4)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q8:_Python_interface">Q8:_Python_interface</A>(5)
<LI><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#/Q9:_MATLAB_interface">Q9:_MATLAB_interface</A>(5)
</B></LI></UL>
<UL>
<UL class=headlines>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#faq101">Some courses
which have used libsvm as a tool</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#faq102">Some
applications which have used libsvm </A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f201">Where can I
find documents of libsvm ?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f202">Where are
change log and earlier versions?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f203">I would like
to cite libsvm. Which paper should I cite ? </A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f204">I would like
to use libsvm in my software. Is there any license problem?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f205">Is there a
repository of additional tools based on libsvm?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f206">On unix
machines, I got "error in loading shared libraries" or "cannot open shared
object file." What happened ? </A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f207">I have
modified the source and would like to build the graphic interface "svm-toy"
on MS windows. How should I do it ?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f208">I am an MS
windows user but why only one (svm-toy) of those precompiled .exe actually
runs ? </A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f209">What is the
difference beween "." and "*" outputed during training? </A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f301">Why sometimes
not all attributes of a data appear in the training/model files ?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f302">What if my
data are non-numerical ?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f303">Why do you
consider sparse format ? Will the training of dense data be much slower
?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f304">Why sometimes
the last line of my data is not read by svm-train?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f305">Is there a
program to check if my data are in the correct format?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f306">May I put
comments in data files?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f401">The output of
training C-SVM is like the following. What do they mean?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f402">Can you
explain more about the model file?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f403">Should I use
float or double to store numbers in the cache ?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f404">How do I
choose the kernel?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f405">Does libsvm
have special treatments for linear SVM?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f406">The number of
free support vectors is large. What should I do?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f407">Should I scale
training and testing data in a similar way?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f408">Does it make a
big difference if I scale each attribute to [0,1] instead of [-1,1]?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f409">The prediction
rate is low. How could I improve it?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f410">My data are
unbalanced. Could libsvm handle such problems?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f411">What is the
difference between nu-SVC and C-SVC?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f412">The program
keeps running (without showing any output). What should I do?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f413">The program
keeps running (with output, i.e. many dots). What should I do?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f414">The training
time is too long. What should I do?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f415">How do I get
the decision value(s)?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f4151">How do I get
the distance between a point and the hyperplane?</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f416">On 32-bit
machines, if I use a large cache (i.e. large -m) on a linux machine, why
sometimes I get "segmentation fault ?"</A>
<LI class=headlines_item><A
href="http://www.csie.ntu.edu.tw/~cjlin/libsvm/faq.html#f417">How do I
disable sc
