Hi!
I have created a program which reads a file, which is constantly updated with new entries/lines - in real time. The file gets written because of a measurement process which takes an arbitrary amount of time. So basically it is an infinite while loop which appends all entries to a list and constantly checks for new entries/lines to append to the list. You can break out of the while loop by pressing a button in a GUI.
A sketch of the code would look like this:
data = []
while True:
.........
for line in f:
data.append(float(line))
.......
if something:
break
Now in the while loop I want to fill a histogram in real time with each new datapoint. The problem is, how do I adapt the number of bins? As a rule of thumb I want my number of bins to be the square root of my number of entries. But my number of entries depends on how long I measure, that is how long my original file is being written. And as I have understood I have to define my histogram before the while loop and set a number of bins.
So it I think of something like this:
data = []
h = ROOT.TH1D("h", "Histogram", ????????? , 0, 0)
c1 = ROOT.TCanvas()
while True:
.........
for line in f:
data.append(float(line))
h.Fill(data[-1])
.......
if something:
break
h.Draw()
c1.Update()
But to set the number of bins I have to know how much entries I will have in advance. But that is not possible.
How would I go about this? Thank you.