Undefined function or variable 'assume', is it possible that my 'assume' function has been removed?

I've encountered with error Undefined function or variable 'assume' although i have used it many times before,

i used these commands below:

restoredefaultpath
rehash toolboxcache

but nothing changed, is it possible that my 'assume' function has been removed and if yes, what should i do?

Answer 1

[Walter Roberson]

If you got through

syms

but fail on assume(), then either your installation is corrupt or you have the Maple based symbolic engine installed. The Maple symbolic engine was the symbolic engine up to R2007a (I think it was). The Maple symbolic engine can end up getting installed if you install the Maple software package (from Maplesoft) and you let the Maple installer install the "MATLAB Connector for Maple".

[saeed shekari]

I think so, but what should i do to solve the problem??

[Walter Roberson]

Are you using an old version of MATLAB, or did you install Maple? If you did install Maple, then do you also have the MATLAB Symbolic Toolbox? If you do then use pathtool to remove the Maple entries from your path.

[Guodong Liang]

Hello, I got the same problem with this function 'assume'.

I have add this line in my codes

rmpath('C:\Program Files\MATLAB\R2017a\toolbox\maple')

but then when I run this codes, it returns

Undefined function or variable 'syms'.

I have also tried

rmpath('C:\Program Files\MATLAB\R2017a\toolbox\maple') addpath('C:\Program Files\MATLAB\R2017a\toolbox\symbolic')

but it also doesn't work. Could you please tell me what should I do in this case?

[Walter Roberson]

It has been a while, but I seem to recall that if you look in C:\Program Files\MATLAB\R2017a\toolbox\maple that there should be an uninstaller executable that will remove the MATLAB Connector for Maple. You might need to (re-) install Mathworks' Symbolic Toolbox after that.

Answer 2

[Ameer Hamza]

You cannot call assume() without input arguments. Use it like this

syms x
assume(x>0);

[saeed shekari]

I have used 'assume' function as follows:

 syms b11 b12 b13 b21 b22 b23 b31 b32 b33 b41 b42 b43 h1 h2 h3
 assume([b11 b12 b13 b21 b22 b23 b31 b32 b33 b41 b42 b43 h1 h2 h3],'real')

i had used it many times before and it was working, but now it shows the error below:

   Undefined function or variable 'assume'. Error in project1 (line 4) assume([b11 b12 b13 b21 b22 b23 b31 b32 b33 b41 b42 b43 h1 h2 h3],'real')

[Ameer Hamza]

Can you show the output of

which assume

at command window