import numpy as np
data4=np.load('time-seriesE4.npy')

intervals=np.diff(data4[0])
print(intervals)
print("Time interval between each individual potential recording =", intervals[0]*1000,"ms")
sampling_rate=1/intervals[0]
print("Sampling rate =",sampling_rate,"Hz")

```
[4.e-05 4.e-05 4.e-05 ... 4.e-05 4.e-05 4.e-05]
Time interval between each individual potential recording = 0.04 ms
Sampling rate = 24999.999999999996 Hz
```

mean_1=np.mean(data4[1,0:2000])
print("Mean of the first 2000 data-points=",mean_1*1000,"mV")
mean_2=np.mean(data4[1,25000:27000])
print("Mean of all data-points between the 25,000th and 27,000th element=", mean_2*1000,"mV")

```
Mean of the first 2000 data-points= -64.33576256881894 mV
Mean of all data-points between the 25,000th and 27,000th element= -93.48334108187638 mV
```