diff --git a/setup.py b/setup.py
index a0a66185..bc1c1893 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@
 
 setup(
 	name             = 'spm1d',
-	version          = '0.4.23',
+	version          = '0.4.24',
 	description      = 'One-Dimensional Statistical Parametric Mapping',
 	author           = 'Todd Pataky',
 	author_email     = 'spm1d.mail@gmail.com',
diff --git a/spm1d/__init__.py b/spm1d/__init__.py
index be00ee4e..061a316b 100644
--- a/spm1d/__init__.py
+++ b/spm1d/__init__.py
@@ -16,11 +16,11 @@
 probabilities in Python, Journal of Statistical Software, in press.
 
 
-Copyright (C) 2023  Todd Pataky
+Copyright (C) 2024  Todd Pataky
 '''
 
 
-__version__ = '0.4.23 (2023-12-28)'
+__version__ = '0.4.24 (2024-01-14)'
 
 
 __all__ = ['data', 'io', 'plot', 'rft1d', 'stats', 'util']
diff --git a/spm1d/rft1d/__init__.py b/spm1d/rft1d/__init__.py
index 30fb2c36..166ba7e9 100644
--- a/spm1d/rft1d/__init__.py
+++ b/spm1d/rft1d/__init__.py
@@ -10,7 +10,7 @@
 '''
 
 
-__version__  = '0.1.4 spm1d'   #(2016.10.01)
+__version__  = '0.1.5 spm1d'   #(2024.01.14)
 
 from . import data, distributions, geom, prob, random
 
diff --git a/spm1d/rft1d/prob.py b/spm1d/rft1d/prob.py
index 128ee12e..44c37fe8 100644
--- a/spm1d/rft1d/prob.py
+++ b/spm1d/rft1d/prob.py
@@ -374,7 +374,7 @@ def _as_float(x):
 def _float_if_possible(x):
 	if isinstance(x, np.ndarray):
 		if x.size==1:
-			return float(x)
+			return float( x.ravel()[0] )
 		else:
 			return x
 	else: