Automatically calculate the number of rows that fit on the page

Sorry if this has been discussed elsewhere but I could not find the solution.

I want to calculate an appropriate iDisplayLength at runtime based on the number of rows that fit on the page. Something along the lines of:

floor((tableHeight - headerHeight - footerHeight) / rowHeight)

I've played with setting the table style to 100% but this just autofills to the end of the page with the preset iDisplayLength.

Currently, my code sets iDisplayLength in the default options:

DataTableUtils.getDefaultOptions = function() {
            var options;
            options = {
                iDisplayLength: 32,
                bAutoWidth: false,
                bJQueryUI: true,
                bSort: false,
                bFilter: false,
                bProcessing: true,
                bServerSide: true,
                sAjaxSource: 'notUsed',
                sDom: 't<"F"rip>',
                sScrollY: '900px',
                oLanguage: {
                    sLengthMenu: '_MENU_'
                },
                sPaginationType: 'full_numbers'
            };
            return options;
        };

Edit: This is for a custom GUI that renders and navigates between local htm pages. It is not available online. I ask this question more to see if this is possible and how it would be done. Please let me know if you require more details.