Is possible to change the type of an attribute from an arff with pyweka?-CodePudding

I have an arff like that :

@relation 'Base de datos modelos 1 y 2'

@attribute BMI numeric
@attribute ROM-PADF-KE_D numeric
@attribute Asym-ROM-PHIR(≥8)_discr {No_Bilateral_Asymmetry,Bilateral_Asymmetry}
@attribute Asym_SLCMJLanding-pVGRF(10percent)_discr {No_Bilateral_Asymmetry,Bilateral_Asymmetry}
@attribute Asym_TJ_Valgus_FPPA(10percent)_discr {No_Bilateral_Asymmetry,Bilateral_Asymmetry}
@attribute DVJ_Valgus_KneeMedialDisplacement_D_discr numeric
@attribute Soft-Tissue_injury_≥4days {No,Yes}

@data
18.716444,33,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,0,No
22.182267,41,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,2,No
25.352783,35,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,1,No
21.332873,33,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,0,No
23.085619,25,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,3,Yes
21.428649,42,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,No_Bilateral_Asymmetry,1,No

and i want to change the numeric type of "@attribute DVJ_Valgus_KneeMedialDisplacement_D_discr" to {0,1,2,3}

Is it possible?

CodePudding user response：

You can use the NumericToNominal filter for that purpose.

The attribute that you want to convert is the 6th one, so you need to do something like this:

import weka.core.jvm as jvm
from weka.core.converters import load_any_file, save_any_file
from weka.filters import Filter

jvm.start()
data = load_any_file("/some/where/data_in.arff", class_index="last")

f = Filter(classname="weka.filters.unsupervised.attribute.NumericToNominal", options=["-R", "6"])
f.inputformat(data)
filtered = f.filter(data)

save_any_file(filtered, "/some/where/data_out.arff")

jvm.stop()