How to modify the dataset to fit for the Matlab project's training data

See more:

MatLab

I have a dataset, there are both discrete and continuous data in it. some of the discrete data are not numerical data.

If I want to use some algs in stats toolbox such like decision tree or naive bayes, do I need to modify the data, like to change discrete "text" data to discrete "numerical" data?

My training data file is ".data" file, can I use fread fun in matlab to read it?~
So confused about whether or not I need to modify the data to make all values "number".

Thanks guys.

I find it can not load the data with "unknown text", thus I need to modify the data...
Is that right~?

Does anyone get a clue?