## Querying and totaling certian elements in a list

queries for number of distinct elements in a subarray
number of distinct elements in a range segment tree
mo's algorithm
range sum query problem
segment tree range maximum query
range update point query segment tree
fenwick tree

So I am very new to python and I have created a list of information that looks like this:

the format is Date, Store, Total income(in that day) and transactions(in that day)

```data = [[datetime.datetime(2012, 3, 1, 0), 'PizzaHut', 2839.60, 25], [datetime.datetime(2012, 12, 4, 0), 'Dominoes', 2839.60, 25], [datetime.datetime(2012, 11, 8, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 6, 4, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 8, 12, 0), 'PizzaHut', 2839.60, 25]
```

So essentially what I am trying do is to query to total income of the a certain store. so the user should enter for example 'Sals' and it will total up the income of that store based on the data in the list. There is probably a really simple solution to the problem but I have been looking around on the net and decided it was time for me to ask you guys. if I can get some explanation on how it works that would really help me aswell as it helps me to grow my knowledge! Thank you all for your contributions!

Using `sum()`

Ex:

```import datetime
data = [[datetime.datetime(2012, 3, 1, 0), 'PizzaHut', 2839.60, 25], [datetime.datetime(2012, 12, 4, 0), 'Dominoes', 2839.60, 25], [datetime.datetime(2012, 11, 8, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 6, 4, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 8, 12, 0), 'PizzaHut', 2839.60, 25]]
key = 'Sals'

print( sum(i[2] for i in data if i[1] == key) )
```

Output:

```5679.2
```

Edit as per comment

```import datetime
import collections
data = [[datetime.datetime(2012, 3, 1, 0), 'PizzaHut', 2839.60, 25], [datetime.datetime(2012, 12, 4, 0), 'Dominoes', 2839.60, 25], [datetime.datetime(2012, 11, 8, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 6, 4, 0), 'Sals', 2839.60, 25], [datetime.datetime(2012, 8, 12, 0), 'PizzaHut', 2839.60, 25]]
key = 'Sals'

d = collections.defaultdict(list)
for i in data:
d[i[1]].append(i)

print( "Sum: {0}".format(sum(i[2] for i in d[key])) )
print( "Average: {0}".format(sum(i[2] for i in d[key])/len(d[key])) )
```

Output:

```Sum: 5679.2
Average: 2839.6
```

Group-By Date

```key = datetime.datetime(2012, 12, 4, 0)

d = collections.defaultdict(list)
for i in data:
d[i[0]].append(i)
```

python - Querying and totaling certian elements in a list, So essentially what I am trying do is to query to total income of the a certain store. so the user should enter for example 'Sals' and it will total up the income of that  Querying and totaling certian elements in a list. Ask Question Asked 1 year, 9 months ago. Active 1 year, 9 months ago. Viewed 38 times 0. So I am very new to python

I would build a dictionary if searches be frequent.

```res = {}
def builddict(data):
for ele in data:
res.setdefault(ele[1], 0)
res[ele[1]] += ele[2] * ele[3]

builddict(data)
print (res['Sals'])
```

Range sum queries without updates, Given an array arr of integers of size n. We need to compute sum of elements from index i to index j. The queries consisting of i and j index values will be  To query if the array field contains at least one element with the specified value, use the filter { <field> => <value> } where <value> is the element value. To query if the array field contains at least one element with the specified value, use the filter equal( <field>, <value> ) where <value> is the element value.

```import datetime

from collections import namedtuple

dailySales = namedtuple('Data', ['day', 'store', 'income', 'transactions'])

data = [[datetime.datetime(2012, 3, 1, 0), 'PizzaHut', 2839.60, 25],
[datetime.datetime(2012, 12, 4, 0), 'Dominoes', 2839.60, 25],
[datetime.datetime(2012, 11, 8, 0), 'Sals', 2839.60, 25],
[datetime.datetime(2012, 6, 4, 0), 'Sals', 2839.60, 25],
[datetime.datetime(2012, 8, 12, 0), 'PizzaHut', 2839.60, 25]]

namedData = [dailySales(*i) for i in data]

key = 'Sals'

print(sum(j.income for j in namedData if j.store==key))
#5679.2
```

Queries for number of distinct elements in a subarray, Queries for number of distinct elements in a subarray · Calculate the Sum of GCD over all subarrays Given a array 'a[]' of size n and number of queries q. The DbSet represents a collection of entities of a specific type - the type specified by the type parameter. Queries are specified using Language Integrated Query (LINQ), a component in the .NET Framework that provides query capability against collections in C# or VB. LINQ queries can be written using query syntax or method syntax. Query syntax shares a resemblance with SQL.

Sum data by using a query - Access - Office Support, Access provides several ways to add these sample tables to a and then select a spreadsheet program from the list. The SQL keyword SELECT forms the basis for all SQL querying. Although SELECT technically specifies columns to be used in a query, it is always the first SQL keyword or command in an SQL phrase that includes at least the SQL keyword FROM and often the SQL keyword WHERE.

Count data by using a query - Access - Office Support, Understand ways to count data, count data by using a Total row or by using a totals You can count the number of items in a field (a column of values) by using the by using a totals query instead of a Total row when you need to count some or The following table lists and describes the aggregate functions that Access  LINQ: Test-Driven Learning. This project is aimed to help the user further study LINQ with a test-driven approach. Each unit contains an annotated tutorial and a platform where you can test your understanding of the topic.

List functions, Docs · Power Query M formula language · Power Query M functions; List functions; List functions overview List.NonNullCount, Returns the number of items in a list excluding null values. List. List.InsertRange, Inserts items from values at the given index in the input list. Sum, Returns the sum from a list. The number of elements that match a certain condition. The element that has the greatest or least value. The first element that matches a condition, or the sum of particular values in a specified set of elements. For example, the following query returns the number of scores greater than 80 from the scores integer array:

• @Jasotufy2 To calculate the average just do `print(sum([i[2] for i in data if i[1] == 'Sals'])/len([i for i in data if i[1] == 'Sals']))`
• Just change the key to your required date ex: `key = datetime.datetime(2012, 12, 4, 0)` and this line `d[i[1]].append(i)` to `d[i[0]].append(i)`