I am facing this problem in a WP theme file, as it is not developed anymore. While I am trying to find a replacement to this template, the debug of the site gives me this: Notice: Undefined offset: 1 in /home/***/public_html/wp-content/themes/vip-restaurant/templates/header-footer-sidebars.php on line 18 Warning: A non-numeric value encountered in /home/***/public_html/wp-content/themes/vip-restaurant/templates/header-footer-sidebars.php on line 18 Warning: Division by zero in /home/***/public_html/wp-content/themes/vip-restaurant/templates/header-footer-sidebars.php on line 18 Where at line 18 I find: $width_num = $width_num[0] / $width_num[1]; The entire loop is as follows: $width_num = explode( '-', str_replace( 'cell-', '', $width ) ); $width_num = $width_num[0] / $width_num[1]; $row_width += $width_num; The website looks broken actually, so I am investigating using the debug mode. The php version is 7.4 (there is no way to upgrade the version actually). Can you please help me to face this problem, even if a temporary solution? debug and ad an array, but I am unable to code clearly UPDATE <?php $width = rd_vamtam_get_option( "$area-sidebars-$i-width" ); $fit = ( $width != 'full' ) ? 'fit' : ''; $width_num = explode( '-', str_replace( 'cell-', '', $width ) ); $width_num = $width_num[0] / $width_num[1]; $row_width += $width_num; if ( $row_width > 1 ) { echo '</div><div class="row">'; $row_width = $width_num; } ?>