Eror Using * Inner matrix dimensions must agreee HELP

Hello, here is my inputs

>> t=(0:t:2*pi);
>> y=exp(-0.3*t)*(2*cos(2*t)+4*sin(2*t))

Error using  * 
Inner matrix dimensions must agree.

the two trig values must be in a parenthesis, i do not understand the error any help would be greatly appreciated.

Answer 1

[Star Strider]

Don’t you just hate it when your inner matrix dimensions argue? And over such trivial issues! I remember one time when ... But we can save that for a later time.

You need to vectorise your ‘y’ assignment:

t = pi/10;
t=(0:t:2*pi);
y=exp(-0.3*t).*(2*cos(2*t)+4*sin(2*t))

It produces:

y =

    Columns 1 through 6

       2.0000e+000     3.6122e+000     3.6625e+000     2.4015e+000   502.8544e-003    -1.2485e+000

    Columns 7 through 12

      -2.2548e+000    -2.2863e+000    -1.4991e+000  -313.8960e-003   779.3223e-003     1.4075e+000

    Columns 13 through 18

       1.4271e+000   935.7615e-003   195.9428e-003  -486.4751e-003  -878.6170e-003  -890.8659e-003

    Columns 19 through 21

    -584.1289e-003  -122.3131e-003   303.6716e-003

I created an initial value for ‘t’ that was necessary for the vector ‘t’. Choose the value you want.