typo.matrix

#Since version 0.9.8alpha  foma allows attaching a confusion matrix specification to a network. The command "read cmatrix <filename>" read a confusion matrix and attaches is to the top network on the stack. Subsequent "apply med" commands will use this matrix in determining the minimum cost approximate match to a word. If no confusion matrix is specified  Levenshtein distance is used (insert = substitute = delete = 1).

#The command "print cmatrix" also prints out the confusion matrix attached to the top network in tabular format.

#The format of the confusion matrix should be clear from the following example confusion matrix file:

#--CUT HERE--
#Insert 1
#Substitute 2
#Delete 1
#Cost 1
#a:b c:d
#Cost 3
#:x x: x:y
#--CUT HERE--

#The above snippet specifies a matrix where the default insertion cost is 1 unit  the default substitution cost is 2 units  and the default deletion cost is 1 unit. Also  substituting an "a" with a "b" costs 1 unit  as does substituting a "c" for a "d". Inserting an "x" costs 3 units  as does deleting an "x" and substituting an "x" for a "y".

#All costs must be positive integer values. A cost specification that involves symbols not found in the alphabet of the top network are not included in the matrix  but are warned about.


Insert 
Substitute 1
Delete 1
Cost 1
v:w v:b h:j o:u
Cost 0
a:A e:E i:I o:O p:P 




# Quechua example: substitution of i/e and o/u at zero cost  also spellings with j/h at cost 1