Error: File: Unbalanced or unexpected parenthesis or bracket

BECAUSE THE ERROR IS GENERATED IF THE PARENTHESIS ARE CORRECT

% ******* PROCESOS PREVIOS**********

%1.- Carga el registro a procesar

filename = input('Open file: ', 's');

xc = load (filename);

xc = xc; % Para sismos se pone (+), para los puentes(-)

[N,~] = size(xc);

tc_max = N/sampling_rate;

tc = (delta_t:delta_t:tc_max)'; % Esto genera un vector tiempo

??? Error: File: Untitled2.m Line: 7 Column: 5

Unbalanced or unexpected parenthesis or bracket.