In this article, we will discuss how to fix ValueError: setting array element with a sequence using Python.
Error which we basically encounter when we using Numpy library is ValueError: setting array element with a sequence. We face this error basically when we creating array or dealing with numpy.array.
This error occurred because of when numpy.array creating array with given value but the data-type of value is not same as data-type provided to numpy.
Steps needed to prevent this error:
- Easiest way to fix this problem is to use the data-type which support all type of data-type.
- Second way to fix this problem is to match the default data-type of array and assigning value.
Method 1: Using common data-type
Example : Program to show error code:
Python
# In this program we are demonstrating how different# Data-type can cause value errorimport numpy# Creating multi-dimension arrayarray1 = [1, 2, 4, [5, [6, 7]]]# Data type of array elementData_type = int# This cause Value errornp_array = numpy.array(array1, dtype=Data_type)print(np_array) |
Output:
File “C:\Users\computers\Downloads\he.py”, line 13, in <module>
np_array = numpy.array(array1,dtype=Data_type);
ValueError: setting an array element with a sequence.
We can fix this error if we provide the data type which support all data-type to the element of array:
Syntax:
numpy.array( Array ,dtype = Common_DataType );
Example: Fixed code
Python
# In this program we fix problem by different data-typeimport numpy# Creating multi-dimension arrayarray1 = [1, 2, 4, [5, [6, 7]]]# Object Data type is accept all data-typeData_type = object# Now we fix the errornp_array = numpy.array(array1, dtype=Data_type)print(np_array) |
Output:
[1 2 4 list([5, [6, 7]])]
Method 2: By matching default data-type of value and Array
Example: Program to show error
Python
# In this program we are demonstrating how mismatch# of data-type can cause value errorimport numpy# Creating arrayarray1 = ["Geeks", "For"]# Default Data type of ArrayData_type = strnp_array = numpy.array(array1, dtype=Data_type)# This cause errornp_array[1] = ["for", "Geeks"]print(np_array) |
Output:
File “C:\Users\computers\Downloads\he.py”, line 15, in <module>
np_array[1] = [“for”,”Geeks”];
ValueError: setting an array element with a sequence
Here we have seen that this error is cause because we are assigning array as a element to array which accept string data-type. we can fix this error by matching the data-type of value and array and then assign it as element of array.
Syntax:
if np_array.dtype == type( Variable ):
expression;
Example: Fixed code
Python
# In this program we fix error by mismatch# of data-typeimport numpy# Creating arrayarray1 = ["Geeks", "For"]# Default Data type of ArrayData_type = strnp_array = numpy.array(array1, dtype=Data_type)Variable = ["for", "Geeks"]# First we match the data-typeif np_array.dtype == type(Variable): np_array[1] = Variableelse: print("Variable value is not the type of numpy array")print(np_array) |
Output:
Variable value is not the type of numpy array ['Geeks' 'For']
