Determine whether the given object represents a scalar data-type in Python

To determine whether a given object represents a scalar data-type, use the numpy.issctype() method. This method returns a Boolean result indicating whether the input represents a scalar dtype. If the input is an instance of a scalar dtype, True is returned; otherwise, False is returned.

Syntax

numpy.issctype(rep)

Parameters

rep: The object to check. This can be a dtype, type, or any other object.

Example

First, import the required library −

import numpy as np

# Check various numpy data types
print("Checking NumPy data types:")
print("np.int32:", np.issctype(np.int32))
print("np.int64:", np.issctype(np.int64))
print("np.float32:", np.issctype(np.float32))
print("np.dtype('str'):", np.issctype(np.dtype('str')))

# Check Python built-in values
print("\nChecking Python values:")
print("Integer 100:", np.issctype(100))
print("Float 25.9:", np.issctype(25.9))
print("np.float32(22.3):", np.issctype(np.float32(22.3)))

Checking NumPy data types:
np.int32: True
np.int64: True
np.float32: True
np.dtype('str'): True

Checking Python values:
Integer 100: False
Float 25.9: False
np.float32(22.3): False

How It Works

The issctype() method distinguishes between:

• Scalar dtypes: NumPy data types like np.int32, np.float64, or np.dtype('str') return True
• Scalar values: Actual numeric values or instances return False

Common Use Cases

import numpy as np

# Checking different data types
data_types = [np.int8, np.int16, np.int32, np.int64, 
              np.float16, np.float32, np.float64,
              np.complex64, np.bool_]

print("Scalar data types:")
for dtype in data_types:
    print(f"{dtype.__name__}: {np.issctype(dtype)}")

Scalar data types:
int8: True
int16: True
int32: True
int64: True
float16: True
float32: True
float64: True
complex64: True
bool_: True

Conclusion

Use numpy.issctype() to check if an object represents a scalar data type rather than a scalar value. This method is useful for type validation in NumPy applications where you need to distinguish between data types and actual data instances.