The cell formula is undefined after call sheet.update method.

[huangbo74]

Hi,
Please check cell.fx.recyncFormula function. the code below
this.formula = this.el.attr('data-formula');
will set this.formula as undefined if the element doesn't contain data-formula.

 However the undefined value is not able to clear the cell processed flag. 

in sheet.fx.clearProcessFlag function, only the formula properties is false of cell
will be marked as processed and and not affected:

Thanks,
Bo