pickerView
選択内容が mainMatrix オブジェクトのプロパティに保存されないのはなぜですか?
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
[mainMatrix setM:[[self.numbers objectAtIndex:[pickerView selectedRowInComponent:0]] intValue]];
[mainMatrix setN:[[self.numbers objectAtIndex:[pickerView selectedRowInComponent:1]] intValue]];
}