Error using tf (transfer function)

Getting the following error:

>> sys = tf([1 2],[1 0 10])

Undefined function 'tf' for input arguments of type 'double'.

Using R2018b and control system toolbox is installed.

Answer 1

[Fangjun Jiang]

run "which -all tf" to find out

[James Phegley]

>> which -all tf

C:\Program Files\MATLAB\R2018b\toolbox\mpc\mpc\@mpc\tf.m % mpc method

C:\Program Files\MATLAB\R2018b\toolbox\ident\ident\@idParametric\tf.m % idParametric method

C:\Program Files\MATLAB\R2018b\toolbox\shared\controllib\engine\@StaticModel\tf.m % StaticModel method

C:\Program Files\MATLAB\R2018b\toolbox\dsp\filterdesign\@mfilt\tf.m % mfilt method

C:\Program Files\MATLAB\R2018b\toolbox\signal\signal\@dfilt\tf.m % dfilt method

[Fangjun Jiang]

while other tooltoxes have tf() for transfer function, your Control System Toolbox was not there.

Should have

\MATLAB\R2018b\toolbox\control\ctrlmodels\@tf\tf.m

check your Control System Toolbox

ver control

Answer 2

[Marco Corral Flores]

106/5000

Hi:

I have problems when using the "tf" command

Please could you help me in this regard.

link video youtube: https://youtu.be/Xr3kPGrHGSg

[Fangjun Jiang]

The error message indicates you don't have one of those needed toolboxes