I wanted to calculate the normalized cross-correlation function of two signals.
I use the command
corr = signal.correlate((s1['Strain']-s1['Strain'].mean())/s1['Strain'].std(), (s2['Strain']-s2['Strain'].mean())/s2['Strain'].std(), mode='full') / len(s1['Strain'])
Both signals have the same length, 30 seconds length and 4096 Hz sampling. s1 and s2 are the GW150914 enter link description here
Here is example data
s1: Strain 0 -1.587702e-22 1 -1.425868e-22 2 -1.174897e-22 3 -8.559119e-23 4 -4.949480e-23 . . . . . .
I didn't get the normalized cross-correlation, the maximum value is 0.04 in range $[-1;1]$. Where is mistake?