When calculating a trigonometric function using Matlab GUI, for example, if I press the $7$ button, press the sin button, press the $+$ button, press the $6$ button, and press the cos button, i want to calculate it as sin$(7)+$cos$(6),$ but It is calculated like

cos$($ sin$(7)+6).$

function btn$\_$equation$\_$Callback$($hObject$,$ eventdata, handles$)$

$\%$ hObject handle to btn$\_$eq $($see GCBO$)$

$\%$ eventdata reserved $-$ to be defined in a future version of MATLAB

$\%$ handles structure with handles and user data $($see GUIDATA$)$

v$=$get$($handles$.$etxt$\_$LCD,'String'$)$;

total$=$eval$($v$)$;

set$($handles$.$etxt$\_$LCD,'String',$[$v$,\text{'}=\text{'},$num$2$str$($total$)])$

current$\_$expression $=$ get$($handles$.$etxt$\_$LCD, 'String'$)$;

try

result $=$ eval$($replace$($current$\_$expression, 'sin', 'sind'$))$;

set$($handles$.$etxt$\_$LCD, 'String', num$2$str$($result$))$;

end

function btn$\_$sin$\_$Callback$($hObject$,$ eventdata, handles$)$

$\%$ hObject handle to btn$\_$sin $($see GCBO$)$

$\%$ eventdata reserved $-$ to be defined in a future version of MATLAB

$\%$ handles structure with handles and user data $($see GUIDATA$)$

$\%$ Hints: get$($hObject$,$'String'$)$ returns contents of btn$\_$sin as text

$\%$ str$2$double$($get$($hObject$,$'String'$))$ returns contents of btn$\_$sin as a double

current$\_$value $=$ get$($handles$.$etxt$\_$LCD, 'String'$)$;

output$\_$str $=[\text{'}$sin$(\text{'},$ current$\_$value, $\text{'})\text{'}]$;

set$($handles$.$etxt$\_$LCD, 'String', output$\_$str$)$;

guidata$($hObject$,$ handles$)$;