Digital filter selection for sensor I am having a LM35 sensor which gives $10\textrm{ mV}$ signal per degree rise of temperature. Now I have one question, which digital filter will be the best for this ?

This sensor will be use in very noisy industrial environment. Also digital filter have some cutoff frequency what should be the cutoff frequency set for this filter ? As signal coming from sensor is an analog signal but not a periodic frequency signal.

One I know is FIR Moving average filer. This takes the mean of previous samples. This I do not want to use as I have used it before,
$$
\frac 1N\sum_{n=0}^{N-1}x[k-n]
$$  

If I am right then DFT is not required as I am not interested in the spectrum analysis of the signal coming from LM35 sensor.

Is there any other DSP digital filter which I can use ?
It depends a lot on the kind of noise and how fast you need the sensor to track the true temperature, and how fast you need to read the temp.

If you expect large outliers, a median filter is robust to those kinds of perturbations and they can have a relatively short effective window, and a corresponding fast response.

Following the median filter with a conventional low pass is used in some applications.

As was pointed out in the comments, the better you can define your requirements, the better you can make your measurements.

The nice thing about using a median,it is a rank statistic that it is core to nonparametric statistics, where fewer assumptions are made by the underlying probability distribution and there is a large literature on how to design hypothesis tests.