warned=False;
	if args.verbose>1: sys.stderr.write("  Iteration %i.\n"%(i));
	viterbi = {}
	noChange=0;
	viterbiCat =np.zeros(allDataCat.shape[0]);
	curTot=0;
	curNumCNVs=0;
	for chr in chrOrder:
		#3. Calculate Viterbi path given data
		if args.verbose>2: sys.stderr.write("    i=%i; Calculating Viterbi path for %s.\n"%(i,chr));
		framelogprob = model._compute_log_likelihood(allData[chr])
		#sys.stderr.write("framelogprob dim: "+str(framelogprob.shape)+"\n");
		framelogprob[:,cnvsToStateIs[args.ploidy]] = np.subtract(framelogprob[:,cnvsToStateIs[args.ploidy]], args.standardPrior); #add log(prior)
		if args.scalePDF>0:
			framelogprob = np.subtract(framelogprob,statePDFMaxima) #### This requires some explanation.  See Note 1 below. 
		logprob, viterbi[chr] = model._do_viterbi_pass(framelogprob);
		curLen = len(viterbi[chr]);
		#4. For each non-standard state, calculate the mean in that state and add a state with a mean representing that ploidy
		changeStart=-1
		viterbi[chr] = np.insert(viterbi[chr],[0,curLen],[normalState,normalState]); # add initial and terminal normalStates so that telomeres in CNV will be detected.
		for j in range(1,len(viterbi[chr])):
			if viterbi[chr][j]!=viterbi[chr][j-1]:#there was a change
				if changeStart==-1:
					if viterbi[chr][j]==normalState:
						raise Exception("new state is normal ploidy state");
					changeStart=j;
				else: #from changeStart to j-1
					#calculate the means of this region
					localMean = np.mean(allData[chr][changeStart:j,:],axis=0);
					#figure out the local CN as the local means divided by the global means, rounded to the nearest logical ploidy
					meanRatio = np.divide(localMean,meanNormal);