Odoo IndexError: list assignment index out of range - odoo

Question

I just create a module. After adding values and got the problem IndexError: list assignment index out of range. How to fix it. Re Edit code please.
Here is my code:
class calculator(osv.osv):
_name = 'calculator.calculator'
def get_total(self, cr, uid, ids, field_name, arg, context):
res = []
perfos = self.browse(cr, uid, ids, context)
for perfo in perfos:
res[perfo.id] = perfo.p + perfo.b
return res
_columns = {
'p':fields.selection(((1,'Outstanding'), (2,'Well Above Expectations'), (3,'As Expected'), (4,'Below Expectations'), (5,'VeryPoor'), (0,'N/A')),'title'),
'b':fields.selection(((1,'Outstanding'), (2,'Well Above Expectations'), (3,'As Expected'), (4,'Below Expectations'), (5,'Very Poor'), (0,'N/A')),'title'),
'total' : fields.function(get_total, method=True, string='Total Mark'),
}

Answer 1

You need to return a dictionary of dictionary for functional fields. You defined res as list and tried to assign as the dictionary. res[perfo.id] is considered as list and index value perfo.id is not found in the res list. That is what the error says. Now the code will be
class calculator(osv.osv):
_name = 'calculator.calculator'
def get_total(self, cr, uid, ids, field_name, arg, context):
res = {}
for perfos in self.browse(cr, uid, ids, context):
res[perfos.id] = perfos.p + perfos.b
return res
_columns = {
'p':fields.selection(((1,'Outstanding'), (2,'Well Above Expectations'), (3,'As Expected'), (4,'Below Expectations'), (5,'VeryPoor'), (0,'N/A')),'title'),
'b':fields.selection(((1,'Outstanding'), (2,'Well Above Expectations'), (3,'As Expected'), (4,'Below Expectations'), (5,'Very Poor'), (0,'N/A')),'title'),
'total' : fields.function(get_total, method=True, string='Total Mark'),
}
For the above code you probably get this js error Error: [_.sprintf] expecting number but found string
I don't get the point adding up two selection fields. The key will get added up like 1+1 in a unicode format.
This following code will give you the basic idea of functional fields.
class calculator(osv.osv):
_name = 'calculator.calculator'
def get_total(self, cr, uid, ids, field_name, arg, context):
res = {}
for perfos in self.browse(cr, uid, ids, context):
res[perfos.id] = perfos.p + perfos.b
return res
_columns = {
'p':fields.integer('A'),
'b':fields.integer('B'),
'total' : fields.function(get_total, method=True, string='Total Mark'),
}
You may need to look at
How to set store trigger for computed fields in Odoo 8?
Function field is not working in OpenERP