How can I change linspace with another function ?

Hi

I have done a program Matlab on which the wanted result is the voltage.

The wanted obtained maximum voltage is 85V/g, however the obtained max value is 564 V/g.

The problem is the use of linspace. If I change the parameter the result change.

Please can you help me to change linspace or rectify the result.

The program must display fresont =26.6 Hz and maxV = 85 V/g.

The problem in omega = linspace (125.66 , 188.5, 1000)';

The input and main prog are attached.