feature('setprecision') in matlab 2022

Hello, currently I have matlab 2022a. It seems the command

feature('setprecision')

does not work in it. The function feature itself works but does can not find setprecision. It shows the following error message:

Error using feature
Feature precision not found

Is there a way around this?

Thank you.

Answer 1

[Venkat Siddarth]

Hi Elsiddig

I understand that you are facing issues in using feature function with setprecison parameter.

The feature('setprecision') command is used to set the precision of the numeric calculations in MATLAB. However, it is an undocumented command and shouldn't be used.

One possible workaround, is to use the vpa() function to perform calculations with a higher precision. vpa() stands for variable precision arithmetic and allows you to specify the desired number of digits for your calculations.

For example, you can use the following code to perform a calculation with 100 digits of precision:

digits(100) %Digits function is used to set the precison used by vpa, by default it is 32 bits

a = vpa(pi)

a = 

3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117068

%But if you want to explicitly change the precison of  specific variables you can
%do it as follows and it wont effect the value of "digits".
b = vpa(exp(1),10)

b = 

2.718281828

%Note: Arithmetic operation happen according to the value of digits
c=a*b

c = 

8.539734222673566611300185395393428880590006981651537285035011588320340680535960171405242699594003394

I hope this resolves the issue

Venkat Siddarth V.

[EDIT: Updated text to clarify about feature function]

[Stephen23]

"The feature('setprecision') command is used to set the precision of the numeric calculations in MATLAB. "

The FEATURE function has never been documented. But now we have an official statement from TMW staff, what it is used for. Can you also provide a link to some documentation for this function?

[Oliver Jaehrig]

@Stephen23 As you mentioned, this is an undocumented command and should not be used by end users.

Since it is not documented, there is no link existing for a published documentation.

In this thread the solution is to use a documented command (vpa).