This is my table:
![Image]()
The "A" column is my X-axis tick value, but I don't want the date, only the time.
This is the command:
$xAxisTickValues = array(
new PHPExcel_Chart_DataSeriesValues('String', 'Inverter'.$inv.'!$A$2:$A$'.count($impianti[$imp]["inverter".$inv]), ...),
);
So, I've tried to substitute with:
substr('Inverter'.$inv.'!$A$2:$A$'.count($impianti[$imp]["inverter".$inv]), 10)
but it give me this error:

The "A" column is my X-axis tick value, but I don't want the date, only the time.
This is the command:
$xAxisTickValues = array(
new PHPExcel_Chart_DataSeriesValues('String', 'Inverter'.$inv.'!$A$2:$A$'.count($impianti[$imp]["inverter".$inv]), ...),
);
So, I've tried to substitute with:
substr('Inverter'.$inv.'!$A$2:$A$'.count($impianti[$imp]["inverter".$inv]), 10)
but it give me this error:
Warning: strtoupper() expects parameter 1 to be string, array given in /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Cell.php on line 683Fatal error: Uncaught exception 'PHPExcel_Exception' with message 'Cell coordinate can not be zero-length string' in /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Cell.php:555 Stack trace: #0 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Cell.php(693): PHPExcel_Cell::coordinateFromString(NULL) #1 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Cell.php(712): PHPExcel_Cell::rangeBoundaries(Array) #2 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Chart/DataSeriesValues.php(304): PHPExcel_Cell::rangeDimension(Array) #3 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Chart/DataSeries.php(361): PHPExcel_Chart_DataSeriesValues->refresh(Object(PHPExcel_Worksheet), false) #4 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Chart/PlotArea.php(124): PHPExcel_Chart_DataSeries->refresh(Object(PHPExcel_Worksheet)) #5 /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Chart.php(523): PHPExcel_Chart_PlotArea->refresh(Object(PHPExcel in /Users/tommaso/Desktop/Tom/Web/perla/phpexcel/Classes/PHPExcel/Cell.php on line 555