loop through each row of data and insert data back & how to preallocate

I am returning about 13000 records from the db and then looping through each row to apply the bndprice and accrbond function. Then I am inserting back the 13000 rows. Question:

1) How do I preallocate the monthlyTotals cell array? w/o preallocating, it's taking about 10mins to calculate.

2) Is this the most efficient way of doing this (looping through record set and inserting results back?)

curs = fetch(curs);
[rows,cols]=size(curs.Data);
for i = 1:rows
    price = bndprice( [curs.Data{i,2}],  [curs.Data{i,3}],  [curs.Data{i,5}], [curs.Data{i,6}], 'Basis', 1, 'DiscountBasis',1);
    acc = acrubond([curs.Data{i,4}],  [curs.Data{i,5}], [curs.Data{i,4}], 100, [curs.Data{i,3}], 2, 1);
    trans = [curs.Data{i,1}];
    % adds rows to monthlyTotals
    monthlyTotals(i,:)=num2cell([price,acc,trans]);   
end
colNames{1,1} = 'AmortizedCost';
colNames{1,2} = 'AccruedInterest';
colNames{1,3} = 'TransactionsId';
insert(conn,'DailyAccruedIncome',colNames,monthlyTotals)

Answer 1

[Fangjun Jiang]

To pre-allocate, do this after you get the size:

monthlyTotals=cell(rows,1)

Then to do the assignment,

monthlyTotals(i)={[price,acc,trans]}

All the other places where you have [curs.Data{i,2}], [curs.Data{i,3}], you don't need the square bracket. That might save you some time too.