What is the complex() function in Python?
The complex() function is used to convert numbers or strings into a complex number. The first parameter corresponds to the real part. The second, which is optional, specifies the imaginary part of that complex number.
Signature
Complex([real[,imaginary]])
Parameters
real: It is the first argument that is a numerical parameter.imaginary(Optional): It is the second argument that is also a numerical value.
Both values are zero by default.
If the first parameter passed to this method is a string or a character array, it will be interpreted as a complex number. In that case, passing the second parameter would throw an error.
Return
The complex() method returns a complex number. It can also accept and return double-precision floating point values.
Exception Handling
If a string that is not a valid complex number is passed as an argument, it returns a ValueError exception error.
Code
Here are a few examples of complex() to get to know how to use it:
- Case #1: This one is a simple example in which we use
complex()function. We are passing only integer type arguments here. - Case #2: We are passing arguments of float type here and the output that is generated by the function is also a float type.
- Case #3: This method allows a string parameter to be passed provided it is a string representation of a numeric value. The numeric value can be either an integer or a floating-point value. It is important to note that if we are passing a string as the first argument, the function will not accept the second argument. Passing a second value would give an error.
- Case #4: It permits only one string parameter. If the first argument is a string type, then it does not allow passing the second argument. It will generate an error if we pass the second parameter.
TypeError: complex() can't take second arg if first is a string - Case #5: It allows passing a complex number as a parameter formatted like
(a+bj) where a,b ∈ ℝ. - Case #6: Although this method allows passing the first argument as a string value, it only allows strings that contain numeric values. It will generate the above error.
ValueError: complex() arg is a malformed string
Check out the following example:
# Python complex() function example# Calling functionx = complex(4) # Passing single parametery = complex(2,5) # Passing both parameters# Displaying resultprint(x)print(y)
