diff --git a/src/get_reads.py b/src/get_reads.py
index edb3822..4410948 100644
--- a/src/get_reads.py
+++ b/src/get_reads.py
@@ -53,7 +53,6 @@ def make_barcodeDict(chrom):
 	disc_mate_pairs = dict()
 	split_reads = collections.defaultdict(list)
 	LRs_by_pos = collections.defaultdict(list)
-	lengths = sum(reads.lengths)
 	iterator = reads.fetch(chrom)
 	starttime = time.time()
 	prevtime = starttime
diff --git a/src/global_vars.py b/src/global_vars.py
index 36f04b6..c2f9e4b 100644
--- a/src/global_vars.py
+++ b/src/global_vars.py
@@ -77,6 +77,9 @@ def estimate_lmin_lmax():
 	num = 0
 	for i,chrm in enumerate(reads.references):
 		for read in reads.fetch(chrm):
+			if read.is_unmapped or read.mate_is_unmapped:
+				continue
+
 			num += 1
 			if num > 1000000:
 				break
@@ -84,10 +87,8 @@ def estimate_lmin_lmax():
 				if read.reference_start > mate_pairs[read.query_name][0]:
 					dist = read.reference_start-mate_pairs[read.query_name][1]
 				else:
-					try:
-						dist = mate_pairs[read.query_name][0]-read.reference_end
-					except:
-						pass
+					dist = mate_pairs[read.query_name][0]-read.reference_end
+
 				if abs(dist) < 2000:
 					length.append(read.query_length)
 					ls.append(dist)