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cjlin1 / libsvm

LIBSVM -- A Library for Support Vector Machines
https://www.csie.ntu.edu.tw/~cjlin/libsvm/
BSD 3-Clause "New" or "Revised" License
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When using svm-scale , missing values come out. #213

Closed Endlesswinds closed 5 months ago

Endlesswinds commented 5 months ago

The original dataset had no missing values, but once I used svm-scale , the result consists of donzons of missing values. Why?

cjlin1 commented 5 months ago

Please see the following libsvm faq:

Q: Why sometimes not all attributes of a data appear in the training/model files ?

libsvm uses the so called "sparse" format where zero values do not need to be stored. Hence a data with attributes

1 0 2 0

is represented as

1:1 3:2