Python Array Value Error

1. Resolve the ValueError: only 2 non-keyword arguments accepted in Python
2. Resolve the ValueError: setting an array element with a sequence
3. Matched Default Data-Type of Array and Values

A Value Error in Python happens when a function gets an argument of the right type, but the value of the type is incorrect. Another error occurs when the NumPy array has more than one element, which causes the error.

This article will discuss the syntax error and how to fix it.

Resolve the ValueError: only 2 non-keyword arguments accepted in Python

In the below example, the NumPy array is 2-dimensional, but afterward, we mixed in a single-dimensional array as well. Python recognizes this as an inhomogeneous shape, indicating that the array’s structure fluctuates, and hence Python raises a value error.

Code Example:

import numpy as np
print(np.array([1, 'English'], [2, 'Spanish'], [3, 'German'], dtype=object ))

Output:

ValueError: only 2 non-keyword arguments accepted

The array should have identical elements to solve this error by creating the array with the same dimensions.

Code Example:

import numpy as np
print(np.array([[1, 'English'], [2, 'Spanish'], [3, 'German']], dtype=object))

Output:

[[1 'English']
[2 'Spanish']
[3 'German']]

Resolve the ValueError: setting an array element with a sequence

Creating multidimensional Arrays using library NumPy sometimes encounters a ValueError. It occurs when setting an array element with a sequence error.

Code Example:

import numpy
arrayeven = [2, 4, 6, [8, [10, 12]]]
np_array = numpy.array(arrayeven, dtype=int)

Output:

ValueError: setting an array element with a sequence

We can use a data type that supports all data types(a common data type) to solve this error. In the following example we’ve used dtype=object instead of dtype=int.

Code Example:

import numpy
arrayeven = [2, 4, 6, [8, [10, 12]]]
np_array = numpy.array(arrayeven, dtype=object)
print(np_array)

Output:

[2 4 6 list([8, [10, 12]])]

Matched Default Data-Type of Array and Values

In the below example, the error occurs due to the assignment of an array as an element of an array that accepts string data.

Code Example:

import numpy
array = ["meeting", "the","is", "at", "10pm"]
newarray = numpy.array(array, dtype=str)
newarray[1] = ["the","meeting", "is", "at", "10pm"]
print(newarray)

Output:

ValueError: setting an array element with a sequence

We can solve this error by matching the data types of the value and the array. We may correct this issue and assign the value as an array element.

Code Example:

import numpy
array = ["meeting", "the","is", "at", "10pm"]
newarray = numpy.array(array, dtype=str)
Variable = ["the","meeting", "is", "at", "10pm"]
if newarray.dtype == type(Variable):
    newarray[1] = Variable
else:
    print(" Type of value and newarray is not same ")
print(newarray)

Output:

Type of value and newarray is not same
['meeting' 'the' 'is' 'at' '10pm']

Using library NumPy, we sometimes encounter Value Errors. It happens when a function might pass the right argument type, but the value of that type is incorrect.

We can fix the Array Value Error using the abovementioned methods.