Error in the coherence calculation

[thelampire]

There are three issues:

1. The first data point in the coherence can have a wrong value.

2. Coherence can have a value > 1

3. Coherence is not unity when interval_n=1

[thelampire]

Also, for cross-correlation, the [0,0] pixel has unity or higher correlation probably due to the same reason as the coherency malfunction.

[thelampire]

I found the error. There were multiple lines line the following in plot.py for error checking:

try:
    d[0,0] += 1

This actually adds 1 to the data object, but otherwise doesn't do any good. In thelampire-patch-3 I fixed it to:

try:
    d[0,0]+1