Is this a bug of MATLAB?

% Here is my code
[vpa(str2sym('asin(1)*2'),100);vpa(str2sym('pi'),100)] 

The output is:

3.1415926535897932384626433832795

3.1415926535897932384626433832795

I think the correct answer should be longer. Is it a bug or an expected behavior?

Answer 1

[Stephen23]

"I think the correct answer should be longer. Is it a bug or an expected behavior?"

It is not a bug: the default number of digits is 32:

https://www.mathworks.com/help/symbolic/digits.html

When you create a new symbolic array it will be displayed using the default number of digits:

d = digits

d = 32

a = vpa(str2sym('asin(1)*2'),100)

a = 

3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117068

b = vpa(str2sym('pi'),100)

b = 

3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117068

c = [a,b] % uses the default number of digits

c = 

d = digits(100) % returns the PREVIOUS default digits, set NEW default digits

d = 32

c = [a,b]

c = 

[Image Analyst]

@M. Wang, pi has an infinite number of digits. Obviously not all of them can be displayed. How many digits did you expect to be installed, and how many do you want or need to be displayed?