Linear phase FIR filter design using Window function

In this experiment we implemented FIR filter using Windowing method for LPF and BPF. In this method, the impulse response is multiplied to window function w(n) to get h(n) which after Z-transform results in the  transfer function H(z). The various inputs for designing are given such as pass band and stop band attenuation, passband and stopband frequencies and sampling frequency. We have to select an appropriate window function w(n) wrt the inputted values.The types of window function are [1] Rectangular [2] Bartlett [3] Hanning [4] Hamming [5] Blackman. We select the window function if its stopband attenuation is more than that of the given filter. The length of the signal i.e. N should always be odd. We selected the Hamming window function and the order of filter came to be 10 and length was 11 for LPF and 14 and 15 for BPF respectively.

code:

https://drive.google.com/open?id=0BxpSA0zcKUVjeEc1azVzZFFINExVYzRTeWtoM2daX1R0dVNr

https://drive.google.com/open?id=0BxpSA0zcKUVjM05FYnU4alJmMlhQYVhFNnlsX0VOdmR3eDg4