I have a column name Total. 
And I'm also using the footer 
value of the jqgrid. 
Example this is the column 
Total 
100 
-98
-76
98
76
how can I get the sum of the row 
using the footer data.
here is my code. 
note: if i use 'sum' it gives me 'NaN' 
value. 
var parseTotal= grid.jqGrid('getCol', 'Total', false, 'sum');
grid.jqGrid('footerData', 'set', { Total: parseTotal});
