You can find an example for classifying a data using Matlab in the following link
http://www.igi.tugraz.at/lehre/EW/tutorials/nnt_intro/index.html
In the file 'nnt_intro_classification.m' it creates NN with 5 hidden units, 3 output units, logsig activation function for each layer. You need to change the configuration to improve the performance and refer to the pdf file in the downloaded zipped file.