How can we classify text file using libsvm?

I am using this code but it is unable to classify the excel file what steps should be taken to classify this file

clc; clf; clear all; close all;

%% Load the full text

[a, b, c] = xlsread('fulltext.xlsx');

load FeatureSelectionGroup

numFeatures = 423;

%% Define FeatureSelectionGroup

FeatureSelectionGroup = cell(numFeatures,1);

FeatureSelectionGroup(1:223) = cellstr('Course');

FeatureSelectionGroup(224:423) = cellstr('NonCourse');

%% Select features

data = [b(:,2), b(:,4)];

groups = ismember(FeatureSelectionGroup,'Course');

[train, test] = crossvalind('holdOut',groups);

cp = classperf(groups);

svmStruct = svmtrain(data(train,:),groups(train),'showplot',true,'boxconstraint',1e6);

title(sprintf('Kernel Function: %s',func2str(svmStruct.KernelFunction)),'interpreter','none');

%classes = svmclassify(svmStruct,data(test,:));%,'showplot',true);

classperf(cp,classes,test)

Thanks for your answers