$_includeCharts : boolean
Write charts that are defined in the workbook? Identifies whether the Writer should write definitions for any charts that exist in the PHPExcel object;
setIncludeCharts(boolean $pValue = FALSE) : \PHPExcel_Writer_IWriter
Set write charts in workbook Set to true, to advise the Writer to include any charts that exist in the PHPExcel object.
Set to false (the default) to ignore charts.
getPreCalculateFormulas() : boolean
Get Pre-Calculate Formulas flag If this is true (the default), then the writer will recalculate all formulae in a workbook when saving, so that the pre-calculated values are immediately available to MS Excel or other office spreadsheet viewer when opening the file If false, then formulae are not calculated on save. This is faster for saving in PHPExcel, but slower when opening the resulting file in MS Excel, because Excel has to recalculate the formulae itself
setPreCalculateFormulas(boolean $pValue = TRUE) : \PHPExcel_Writer_IWriter
Set Pre-Calculate Formulas Set to true (the default) to advise the Writer to calculate all formulae on save Set to false to prevent precalculation of formulae on save.
setUseDiskCaching(boolean $pValue = FALSE, string $pDirectory = NULL) : \PHPExcel_Writer_Excel2007
Set use disk caching where possible?
Disk caching directory
when directory does not exist