Handle nonexistent gnomAD DB

Author: julianhess

capy/seq.py

@@ -77,7 +77,14 @@ class _gnomad:
 	def __init__(self, gnomad_dir = "/mnt/j/db/hg19/gnomad", bin_stem = "chr1-22", ref = None):
 		self.gnomad_dir = gnomad_dir
 		self.bin_stem = bin_stem
+
+		gnomad_index = gnomad_dir + "/1bit/" + bin_stem + ".index.parquet"
+		if not _os.path.isfile(gnomad_index):
+			print("Cannot find path to gnomAD index; gnomAD functionality disabled.", file = _sys.stderr)
+			return
+
 		self.obit_idx = _pd.read_parquet(gnomad_dir + "/1bit/" + bin_stem + ".index.parquet")
+
 		self.ref = ref
 
 		self.mm_1bit = None