added cupy.format_float_positional

cupy/__init__.py

@@ -435,6 +435,7 @@ def result_type(*arrays_and_dtypes):
 from cupy._io.formatting import array_repr  # NOQA
 from cupy._io.formatting import array_str  # NOQA
 from cupy._io.formatting import array2string  # NOQA
+from cupy._io.formatting import format_float_positional  # NOQA
 
 from cupy._io.text import savetxt  # NOQA
 

cupy/_io/formatting.py

@@ -52,3 +52,14 @@ def array2string(a, *args, **kwargs):
 
     """
     return numpy.array2string(cupy.asnumpy(a), *args, **kwargs)
+
+
+def format_float_positional(x, *args, **kwargs):
+    """Format a floating-point scalar as a decimal string in positional notation.
+
+    See :func:`numpy.format_float_positional` for the list of arguments.
+
+    .. seealso:: :func:`numpy.format_float_positional`
+
+    """
+    return numpy.format_float_positional(cupy.asnumpy(x), *args, **kwargs)

docs/source/reference/io.rst

@@ -37,6 +37,7 @@ String formatting
    array2string
    array_repr
    array_str
+   format_float_positional
 
 
 Base-n representations

tests/cupy_tests/io_tests/test_formatting.py

@@ -23,3 +23,14 @@ def test_array2string(self):
         a = testing.shaped_arange((2, 3, 4), cupy)
         b = testing.shaped_arange((2, 3, 4), numpy)
         return cupy.array2string(a) == numpy.array2string(b)
+
+    def test_format_float_positional_python_scalar(self):
+        x = 1.0
+        assert cupy.format_float_positional(
+            x) == numpy.format_float_positional(x)
+
+    def test_format_float_positional(self):
+        a = testing.shaped_arange((1,), cupy)
+        b = testing.shaped_arange((1,), numpy)
+        assert cupy.format_float_positional(
+            a) == numpy.format_float_positional(b)