Add first code experiments

1 files changed, 38 insertions, 0 deletions

diff --git a/autocorrelate.py b/autocorrelate.py
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+++ b/autocorrelate.py
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+#!/usr/bin/env python
+#
+# Do a single autocorrelation over the whole test.16.14.25.iq file
+#
+# Licence: see LICENCE file
+
+import numpy as np
+import matplotlib.pyplot as pp
+
+file_in = "test.16.14.25.iq"
+
+channel_out = np.fromfile(file_in, np.complex64)
+
+print("Autocorrelating")
+
+correlationlength = 50
+
+def autocorrelate(x, length):
+    return np.array([1] + [np.abs(np.corrcoef(x[:-i], x[i:])[0,1]) for i in range(1, length)])
+
+autocorr = autocorrelate(channel_out, correlationlength)
+
+print("Done")
+
+numpeaks = 6
+print("The first {} highest peaks are at".format(numpeaks))
+print("  index: amplitude")
+for ind in autocorr.argsort()[-numpeaks:][::-1]:
+    print("   {:4}: {}".format(ind, autocorr[ind]))
+
+fig = pp.figure()
+ax = fig.add_subplot(111)
+hi = ax.semilogy(autocorr)
+
+
+pp.show()
+
+