diff --git a/misc/finiterectlat-modes.py b/misc/finiterectlat-modes.py
index ac1692c..39b946a 100755
--- a/misc/finiterectlat-modes.py
+++ b/misc/finiterectlat-modes.py
@@ -37,7 +37,7 @@ particlestr = ("sph" if a.height is None else "cyl") + ("_r%gnm" % (a.radius*1e9
 if a.height is not None: particlestr += "_h%gnm" % (a.height * 1e9)
 defaultprefix = "%s_p%gnmx%gnm_%dx%d_m%s_B%s_L%d_c(%s±%g±%gj)eV_cn%d_%s" % (
     particlestr, px*1e9, py*1e9, Nx, Ny, str(a.material), str(a.background), a.lMax,
-    str(a.centre), a.ai, a.ar, a.N,
+    str(a.centre), a.ar, a.ai, a.N,
     thegroup,
     )
 logging.info("Default file prefix: %s" % defaultprefix)