I am building a query for a report with multiple IF conditions on the SUM. I am having problems with a multiple IF conditions on the SUM.

Here is the query:

    SELECT SUM(`totalamount`) AS Total, 
	SUM(`PayPalFee`) AS Fees,
	DATE(`TransactionDate`) AS `Day`, 
	SUM(IF(PaymentType = &quot;paypal&quot;, 1,0)) AS Paypal, 
	SUM(IF(PaymentType = &quot;check&quot;, 1,0)) AS Checks, 
	SUM(IF(PaymentType = &quot;credit card&quot;, 1,0)) AS CreditCard, 
	COUNT(*) AS Entries
     FROM my_table
     WHERE TransactionDate between &#39;2011-05-05&#39; AND &#39;2012-01-30&#39;
     GROUP BY day
     ORDER BY `day` ASC

This query works just fine. 

When I try to add the below conditional SUM statement:

     SUM(&#39;TotalAmount&#39;(PaymentType = &quot;credit card&quot;, 1,0)) AS CreditCardTotal,

This conditional IF statement fails out. 

I have a column called &#39;TotalAmount&#39; and a column called &#39;PaymentType&#39; I am looking to create a SUM of the credit card transactions by each day, a SUM of the checks transactions by each day, a SUM of the paypal transactions by each day,. 
I have tried to create a subquery but this returns a value for the entire TotalAmount column, not broken down by day.

MYSQL Sum Query with IF Condition

I am playing in Python a bit again, and I found a neat book with examples. One of the examples is to plot some data. I have a .txt file with two columns and I have the data. I plotted the data just fine, but in the exercise it says: Modify your program further to calculate and plot the running average of the data, defined by:

    $Y_k=\frac{1}{2r}\sum_{m=-r}^r y_{k+m}$

where `r=5` in this case (and the `y_k` is the second column in the data file). Have the program plot both the original data and the running average on the same graph.

So far I have this:

    from pylab import plot, ylim, xlim, show, xlabel, ylabel
    from numpy import linspace, loadtxt
    
    data = loadtxt(&quot;sunspots.txt&quot;, float)
    r=5.0
    
    x = data[:,0]
    y = data[:,1]
    
    plot(x,y)
    xlim(0,1000)
    xlabel(&quot;Months since Jan 1749.&quot;)
    ylabel(&quot;No. of Sun spots&quot;)
    show()

So how do I calculate the sum? In Mathematica it&#39;s simple since it&#39;s symbolic manipulation (Sum[i, {i,0,10}] for example), but how to calculate sum in python which takes every ten points in the data and averages it, and does so until the end of points?

I looked at the book, but found nothing that would explain this :\

-----------------------------

heltonbiker&#39;s code did the trick ^^ :D


    from __future__ import division
    from pylab import plot, ylim, xlim, show, xlabel, ylabel, grid
    from numpy import linspace, loadtxt, ones, convolve
    import numpy as numpy
    
    data = loadtxt(&quot;sunspots.txt&quot;, float)
    
    def movingaverage(interval, window_size):
        window= numpy.ones(int(window_size))/float(window_size)
        return numpy.convolve(interval, window, &#39;same&#39;)
    
    x = data[:,0]
    y = data[:,1]
    
    
    plot(x,y,&quot;k.&quot;)
    y_av = movingaverage(y, 10)
    plot(x, y_av,&quot;r&quot;)
    xlim(0,1000)
    xlabel(&quot;Months since Jan 1749.&quot;)
    ylabel(&quot;No. of Sun spots&quot;)
    grid(True)
    show()

And I got this: 

![image][1]

Thank you very much ^^ :)


  [1]: http://i.stack.imgur.com/4TyaF.png

Finding moving average from data points in Python

I recently answered a [question on a sister site][1] which asked for a function that counts all even digits of a number. One of the [other answers][2] contained two functions (which turned out to be the fastest, so far):

    def count_even_digits_spyr03_for(n):
        count = 0
        for c in str(n):
            if c in &quot;02468&quot;:
                count += 1
        return count
    
    def count_even_digits_spyr03_sum(n):
        return sum(c in &quot;02468&quot; for c in str(n))

In addition I looked at using a list comprehension and `list.count`:

    def count_even_digits_spyr03_list(n):
        return [c in &quot;02468&quot; for c in str(n)].count(True)


The first two functions are essentially the same, except that the first one uses an explicit counting loop, while the second one uses the built-in `sum`. I would have expected the second one to be faster (based on e.g. [this answer][3]), and it is what I would have recommended turning the former into if asked for a review. But, it turns out it is the other way around. Testing it with some random numbers with increasing number of digits (so the chance that any single digit is even is about 50%) I get the following timings:

[![enter image description here][4]][4]

**Why is the manual `for` loop so much faster?** It&#39;s almost a factor two faster than using `sum`. And since the built-in `sum` should be about five times faster than manually summing a list (as per [the linked answer][3]), it means that it is actually ten times faster! Is the saving from only having to add one to the counter for half the values, because the other half gets discarded, enough to explain this difference?


----------

Using an `if` as a filter like so:

    def count_even_digits_spyr03_sum2(n):
        return sum(1 for c in str(n) if c in &quot;02468&quot;)

Improves the timing only to the same level as the list comprehension.


----------

When extending the timings to larger numbers, and normalizing to the `for` loop timing, they asymptotically converge for very large numbers (&gt;10k digits), probably due to the time `str(n)` takes:

[![enter image description here][5]][5]


  [1]: https://codereview.stackexchange.com/q/220824/98493
  [2]: https://codereview.stackexchange.com/a/220841/98493
  [3]: https://stackoverflow.com/a/24578976/4042267
  [4]: https://i.stack.imgur.com/BbVC2.png
  [5]: https://i.stack.imgur.com/aIhuN.png

Why is a `for` loop so much faster to count True values?

I&#39;m looking for help using sum() in my SQL query:

    SELECT links.id, 
           count(DISTINCT stats.id) as clicks, 
           count(DISTINCT conversions.id) as conversions, 
           sum(conversions.value) as conversion_value 
    FROM links 
    LEFT OUTER JOIN stats ON links.id = stats.parent_id 
    LEFT OUTER JOIN conversions ON links.id = conversions.link_id 
    GROUP BY links.id 
    ORDER BY links.created desc;

I use `DISTINCT` because I&#39;m doing &quot;group by&quot; and this ensures the same row is not counted more than once.

The problem is that SUM(conversions.value) counts the &quot;value&quot; for each row more than once (due to the group by)

I basically want to do `SUM(conversions.value)` for each DISTINCT conversions.id.

Is that possible?

MYSQL sum() for distinct rows

Here I go with my basic questions again, but please bear with me.

In Matlab, is fairly simple to add a number to elements in a list:

    a = [1,1,1,1,1]
    b = a + 1

`b` then is `[2,2,2,2,2]`

In python this doesn&#39;t seem to work, at least on a list.

Is there a simple fast way to add up a single number to the entire list.

Thanks

Sum one number to every element in a list (or array) in Python

I understand that in order to sum array elements in Ruby one can use the inject method, i.e.

    array = [1,2,3,4,5];
    puts array.inject(0, &amp;:+) 

But how do I sum the properties of objects within an object array e.g.?

There&#39;s an array of objects and each object has a property &quot;cash&quot; for example. So I want to sum their cash balances into one total. Something like...

    array.cash.inject(0, &amp;:+) # (but this doesn&#39;t work)

I realise I could probably make a new array composed only of the property cash and sum this, but I&#39;m looking for a cleaner method if possible!


How to sum properties of the objects within an array in Ruby

In `numpy.sum()` there is parameter called `keepdims`. What does it do?

As you can see here in the documentation:
http://docs.scipy.org/doc/numpy/reference/generated/numpy.sum.html

    numpy.sum(a, axis=None, dtype=None, out=None, keepdims=False)[source]
    Sum of array elements over a given axis.
    
    Parameters:	
    ...
    keepdims : bool, optional
        If this is set to True, the axes which are reduced are left in the result as
        dimensions with size one. With this option, the result will broadcast
        correctly against the input array.
    ...

In numpy.sum() there is parameter called &quot;keepdims&quot;. What does it do?

I need to write a query that returns the sum of all values that meet a certain criteria, but the query needs to return 0 if no rows are found, rather than null.  For example:

    tab    
    +---------------+-----+
    | descr         | num |
    +---------------+-----+
    | hello there   | 5   |
    | hi there      | 10  |
    | hello         | 10  |
    | hi there!     | 15  |
    +---------------+-----+

This query:

    SELECT sum(num) AS val FROM tab WHERE descr LIKE &quot;%hello%&quot;;

should, and does, return `15`.  However:

    SELECT sum(num) AS val FROM tab WHERE descr LIKE &quot;%greetings%&quot;;

should return `0`, but does return `null`.

Can someone explain if this is possible?

How to select sum -or- 0 if no records exist?

I&#39;m learning Python from a book, and I came across this example:

    M = [[1,2,3],
         [4,5,6],
         [7,8,9]]
    
    G = (sum(row) for row in M) # create a generator of row sums
    next(G) # Run the iteration protocol

Since I&#39;m an absolute beginner, and the author hasn&#39;t provided any explanation of the example or the next() function, I don&#39;t understand what the code is doing.


Python: next() function

I have defined a JavaScript variables called `myData` which is a `new Array` like this:

    var myData = new Array([&#39;2013-01-22&#39;, 0], [&#39;2013-01-29&#39;, 0], [&#39;2013-02-05&#39;, 0],
                 [&#39;2013-02-12&#39;, 0], [&#39;2013-02-19&#39;, 0], [&#39;2013-02-26&#39;, 0], 
                 [&#39;2013-03-05&#39;, 0], [&#39;2013-03-12&#39;, 0], [&#39;2013-03-19&#39;, 0], 
                 [&#39;2013-03-26&#39;, 0], [&#39;2013-04-02&#39;, 21], [&#39;2013-04-09&#39;, 2]);

I am wondering if it is possible to sum the number values found in the array (ex. 0+0+21+2+0 and so on) and have probably a variable with the result that I can use outside of the script tag because I have 7 of this kind of arrays corresponding for each of the day in the week. I want to make a comparison afterwards based on that. That is the most preferred method for this kind of actions if is possible? 

Sum values from an array of key-value pairs in JavaScript

I want to get N random numbers whose sum is a value.

For example, let&#39;s suppose I want 5 random numbers that sum to 1.

Then, a valid possibility is:

    0.2 0.2 0.2 0.2 0.2

Another possibility is:

    0.8 0.1 0.03 0.03 0.04

And so on. I need this for the creation of a matrix of belongings for Fuzzy C-means.

Getting N random numbers whose sum is M

I have the following DataFrame:

    In [1]:
    df = pd.DataFrame({&#39;a&#39;: [1, 2, 3],
                       &#39;b&#39;: [2, 3, 4],
                       &#39;c&#39;: [&#39;dd&#39;, &#39;ee&#39;, &#39;ff&#39;],
                       &#39;d&#39;: [5, 9, 1]})

    df
    Out [1]:
       a  b   c  d
    0  1  2  dd  5
    1  2  3  ee  9
    2  3  4  ff  1



I would like to add a column `&#39;e&#39;` which is the sum of columns `&#39;a&#39;`, `&#39;b&#39;` and `&#39;d&#39;`.

Going across forums, I thought something like this would work:

    df[&#39;e&#39;] = df[[&#39;a&#39;, &#39;b&#39;, &#39;d&#39;]].map(sum)

But it didn&#39;t.

I would like to know the appropriate operation with the list of columns `[&#39;a&#39;, &#39;b&#39;, &#39;d&#39;]` and `df` as inputs.

Pandas: sum DataFrame rows for given columns

I have a list of objects. One property of the individual object entry is amount. How do I get the sum of amount?

If my list was of type double I may be able to do something like this:

    double total = myList.Sum();

However I want to something similar to this, yet this syntax is incorrect.

    double total = myList.amount.Sum();

How should I go about accomplishing this? I would love to use the Sum function if possible instead of looping through and calculating the value.





C# List of objects, how do I get the sum of a property

I&#39;m having a problem finding the sum of all of the integers in an array in Java. I cannot find any useful method in the `Math` class for this.

How do you find the sum of all the numbers in an array in Java?

Say I have a simple function in MySQL:

    SELECT SUM(Column_1)
    FROM Table
    WHERE Column_2 = &#39;Test&#39;

If no entries in `Column_`2 contain the text &#39;Test&#39; then this function returns `NULL`, while I would like it to return 0. 

I&#39;m aware that a similar question has been asked a few times here, but I haven&#39;t been able to adapt the answers to my purposes, so I&#39;d be grateful for some help to get this sorted.

How do I get SUM function in MySQL to return &#39;0&#39; if no values are found?

***Target***

I have a Pandas data frame, as shown below, with multiple columns and would like to get the total of column, `MyColumn`.
________________

***Data Frame*** - `df`:

*`print df`*

               X           MyColumn  Y              Z   
    0          A           84        13.0           69.0   
    1          B           76         77.0          127.0   
    2          C           28         69.0           16.0   
    3          D           28         28.0           31.0   
    4          E           19         20.0           85.0   
    5          F           84        193.0           70.0   

_____________

***My attempt***:

I have attempted to get the sum of the column using `groupby` and `.sum()`:

    Total = df.groupby[&#39;MyColumn&#39;].sum()

    print Total

This causes  the following error:

    TypeError: &#39;instancemethod&#39; object has no attribute &#39;__getitem__&#39;
_______________

***Expected Output***

I&#39;d have expected the output to be as followed:

    319

Or alternatively, I would like `df` to be edited with a new `row` entitled `TOTAL` containing the total: 

               X           MyColumn  Y              Z   
    0          A           84        13.0           69.0   
    1          B           76         77.0          127.0   
    2          C           28         69.0           16.0   
    3          D           28         28.0           31.0   
    4          E           19         20.0           85.0   
    5          F           84        193.0           70.0   
    TOTAL                  319

Get total of Pandas column

I have the following two lists:

    first = [1,2,3,4,5]
    second = [6,7,8,9,10]

Now I want to add the items from both of these lists into a new list.

output should be 

    third = [7,9,11,13,15]

Add SUM of values of two LISTS into new LIST

How can I add all the columnar values by associative key? Note that key sets are dynamic.  

Input array:

&lt;!-- language: lang-none --&gt;

    Array
    (
        [0] =&gt; Array
            (
                [gozhi] =&gt; 2
                [uzorong] =&gt; 1
                [ngangla] =&gt; 4
                [langthel] =&gt; 5
            )
    
        [1] =&gt; Array
            (
                [gozhi] =&gt; 5
                [uzorong] =&gt; 0
                [ngangla] =&gt; 3
                [langthel] =&gt; 2
            )
    
        [2] =&gt; Array
            (
                [gozhi] =&gt; 3
                [uzorong] =&gt; 0
                [ngangla] =&gt; 1
                [langthel] =&gt; 3
            )
    )

Desired result:

&lt;!-- language: lang-none --&gt;

    Array
    (
        [gozhi] =&gt; 10
        [uzorong] =&gt; 1
        [ngangla] =&gt; 8
        [langthel] =&gt; 10
    )

How to sum all column values in multi-dimensional array?

I have an array of integers.

For example:

    array = [123,321,12389]

Is there any nice way to get the sum of them?

I know, that 

    sum = 0
    array.each { |a| sum+=a }


would work.

How to sum array of numbers in Ruby?

    time_interval = [4, 6, 12]

I want to sum up the numbers like `[4, 4+6, 4+6+12]` in order to get the list `t = [4, 10, 22]`.

I tried the following:

    t1 = time_interval[0]
    t2 = time_interval[1] + t1
    t3 = time_interval[2] + t2
    print(t1, t2, t3)  # -&gt; 4 10 22

How to find the cumulative sum of numbers in a list?

Lets say I have class `C` which has attribute `a`.

What is the best way to get the sum of `a` from a list of `C` in Python?

---

I&#39;ve tried the following code, but I know that&#39;s not the right way to do it:
```
for c in c_list:
    total += c.a
```

Sum / Average an attribute of a list of objects

If I want to find the sum of the digits of a number, i.e.:

  - Input: `932`
  - Output: `14`, which is `(9 + 3 + 2)`

What is the fastest way of doing this?

I instinctively did:

    sum(int(digit) for digit in str(number))

and I found this online:

    sum(map(int, str(number)))

Which is best to use for speed, and are there any other methods which are even faster?


Sum the digits of a number

Are there single functions in pandas to perform the equivalents of [SUMIF][1], which sums over a specific condition and [COUNTIF][2], which counts values of specific conditions from Excel?

I know that there are many multiple step functions that can be used for

for example for `sumif` I can use `(df.map(lambda x: condition), or df.size())` then use `.sum()`

and for `countif` I can use `(groupby functions` and look for my answer or use a filter and the `.count())` 

Is there simple one step process to do these functions where you enter the condition and the data frame and you get the sum or counted results?


  [1]: http://office.microsoft.com/en-us/excel-help/sumifs-function-HA010047504.aspx
  [2]: http://office.microsoft.com/en-us/excel-help/countifs-function-HA010047494.aspx

Pandas counting and summing specific conditions

I have a data frame with several columns; some numeric and some character. **How to compute the&#160;sum of a specific column?** I’ve googled for this and I see numerous functions (`sum`, `cumsum`, `rowsum`, `rowSums`, `colSums`, `aggregate`, `apply`) but I can’t make sense of it all.

For example suppose I have a data frame `people` with the following columns


    people &lt;- read(
      text = 
        &quot;Name Height Weight
        Mary 65     110
        John 70     200
        Jane 64     115&quot;, 
      header = TRUE
    )
    …

How do I get the sum of all the weights?

How to sum data.frame column values?

Here is my code, I need to sum an undefined number of elements in the list. How to do this?

    l = raw_input()
    l = l.split(&#39; &#39;)
    l.pop(0)


My input: `3 5 4 9`
After input I delete first element via `l.pop(0)`.
After `.split(&#39; &#39;)` my list is `[&#39;5&#39;, &#39;4&#39;, &#39;9&#39;]` and I need to sum all elements in this list.

In this case the sum is 18. Please notice that number of elements is not defined.

Summing elements in a list

I have a list of numbers such as `[1,2,3,4,5...]`, and I want to calculate `(1+2)/2` and for the second, `(2+3)/2` and the third,
`(3+4)/2`, and so on. How can I do that?

I would like to sum the first number with the second and divide it by 2, then sum the second with the third and divide by 2, and so on.

Also, how can I sum a list of numbers?

    a = [1, 2, 3, 4, 5, ...]

Is it:

    b = sum(a)
    print b

to get one number?

This doesn&#39;t work for me.



Sum a list of numbers in Python

I have a collection of boxes with the properties weight, volume and owner.

I want to use LINQ to get a summarized list (by owner) of the box information

e.g.

    **Owner, Boxes, Total Weight, Total Volume**  
    Jim,     5,     1430.00,      3.65  
    George,  2,     37.50,        1.22

Can someone show me how to do this with Lambda expressions?

Using GroupBy, Count and Sum in LINQ Lambda Expressions

I have two tables: Toys and Games.

    +--------------------+------------------+
    | Field              | Type             |
    +--------------------+------------------+
    | toy_id             | int(10) unsigned |
    | little_kid_id      | int(10) unsigned |
    +--------------------+------------------+

    +--------------------+------------------+
    | Field              | Type             |
    +--------------------+------------------+
    | game_id            | int(10) unsigned |
    | little_kid1        | int(10) unsigned |
    | little_kid2        | int(10) unsigned |
    | little_kid3        | int(10) unsigned |
    +--------------------+------------------+

A little kid can have multiple toys.
A little kid can be participating in multiple games at once.

I want a query that will give me the total number of toys + games that a little_kid is involved with.

Basically, I want the sum of these two queries:
&lt;pre&gt;
SELECT COUNT(*) FROM Toys WHERE little_kid_id = 900;
SELECT COUNT(*) from Games WHERE little_kid1 = 900 
                              OR little_kid2 = 900 
                              OR little_kid3 = 900;
&lt;/pre&gt;

Is it possible to get this in a single SQL query?  Obviously, I can sum them programmatically, but that&#39;s less desirable.

(I realize that the contrived example makes the schema look ineffecient.  Let&#39;s assume that we can&#39;t change the schema.)

How do I add two count(*) results together on two different tables?

I reckon this will be quite trivial but I can&#39;t work out how to do it. I have a `List&lt;int&gt;` and I want to sum a range of the numbers.

Say my list is:

    var list = new List&lt;int&gt;()
    {
        1, 2, 3, 4
    };

How would I get the sum of the first 3 objects? The result being 6. I tried using `Enumerable.Range` but couldn&#39;t get it to work, not sure if that&#39;s the best way of going about it.

Without doing:

    int sum = list[0] + list[1] + list[2];

Sum range of int&#39;s in List&lt;int&gt;

If I have a dataframe similar to this one

    Apples   Bananas   Grapes   Kiwis
    2        3         nan      1
    1        3         7        nan
    nan      nan       2        3

I would like to add a column like this

    Apples   Bananas   Grapes   Kiwis   Fruit Total
    2        3         nan      1        6
    1        3         7        nan      11
    nan      nan       2        3        5

I guess you could use `df[&#39;Apples&#39;] + df[&#39;Bananas&#39;]` and so on, but my actual dataframe is much larger than this. I was hoping a formula like `df[&#39;Fruit Total&#39;]=df[-4:-1].sum` could do the trick in one line of code. That didn&#39;t work however. Is there any way to do it without explicitly summing up all columns?

Pandas: sum up multiple columns into one column without last column

    from i in Db.Items
    select new VotedItem
    {
        ItemId = i.ItemId,
        Points = (from v in Db.Votes
                  where b.ItemId == v.ItemId
                  select v.Points).Sum()
    }

I got this query, however it fails if no votes are found with exception:

    The null value cannot be assigned to a member with type System.Int32 which is a non-nullable value type.

I assume its because sum returns an int and not a nullable int, giving sum a int? as input only give the same error, probably cause sum only workes on ints.

Any good workaround for this?

Linq query with nullable sum

Using LINQ to SQL, I have an Order class with a collection of OrderDetails.  The Order Details has a property called LineTotal which gets Qnty x ItemPrice. 

I know how to do a new LINQ query of the database to find the order total, but as I already have the collection of OrderDetails from the DB, is there a simple method to return the sum of the LineTotal directly from the collection?

I&#39;d like to add the order total as a property of my Order class. I imagine I could loop through the collection and calculate the sum with a for each Order.OrderDetail, but I&#39;m guessing there is a better way.

Sum of items in a collection

let&#39;s say that I have a table called
Items (ID int, Done int, Total int)

I can do it by two queries:

    int total = m.Items.Sum(p=&gt;p.Total)
    int done = m.Items.Sum(p=&gt;p.Done)

But I&#39;d like to do it in one query, something like this:

    var x = from p in m.Items select new { Sum(p.Total), Sum(p.Done)};
Surely there is a way to call aggregate functions from LINQ syntax...? 


Get sum of two columns in one LINQ query

I have a query that counts the price of all items between two dates. Here is the select statement:

    SELECT SUM(Price) AS TotalPrice 
    FROM Inventory
    WHERE (DateAdded BETWEEN @StartDate AND @EndDate)

You can assume all of the tables have been set up properly.

If I do a select between two dates and there are no items within that date range, the function returns NULL as the TotalPrice rather than 0.

How can I make sure that if no records are found, 0 gets returned rather than NULL?



How can I change NULL to 0 when getting a single value from a SQL function?

Python has a built in function `sum`, which is effectively equivalent to:

    def sum2(iterable, start=0):
        return start + reduce(operator.add, iterable)

for all types of parameters except strings. It works for numbers and lists, for example:

     sum([1,2,3], 0) = sum2([1,2,3],0) = 6    #Note: 0 is the default value for start, but I include it for clarity
     sum({888:1}, 0) = sum2({888:1},0) = 888

Why were strings specially left out?

     sum( [&#39;foo&#39;,&#39;bar&#39;], &#39;&#39;) # TypeError: sum() can&#39;t sum strings [use &#39;&#39;.join(seq) instead]
     sum2([&#39;foo&#39;,&#39;bar&#39;], &#39;&#39;) = &#39;foobar&#39;


I seem to remember discussions in the Python list for the reason, so an explanation or a link to a thread explaining it would be fine.

**Edit**: I am aware that the standard way is to do `&quot;&quot;.join`. My question is why the option of using sum for strings was banned, and no banning was there for, say, lists.

**Edit 2**: Although I believe this is not needed given all the good answers I got, the question is: *Why does sum work on an iterable containing numbers or an iterable containing lists but not an iterable containing strings?*

Python sum, why not strings?

I have a table:

    ref,type
    1,red
    2,red
    3,green
    4,blue
    5,black
    6,black

I want the result of a sqlite query to be:

    red,2
    green,1
    blue,1
    black,2

I think the hardest thing to do is find a question to match my problem?  Then I am sure the answer is around the corner....

:)

How can I count how many duplicates there are for each distinct value in sqlite?

Let&#39;s say I have a dictionary in which the keys map to integers like:

    d = {&#39;key1&#39;: 1,&#39;key2&#39;: 14,&#39;key3&#39;: 47}

Is there a syntactically minimalistic way to return the sum of the values in `d`—i.e. `62` in this case?


How to sum all the values in a dictionary?

I&#39;m trying to update a field in the database to the sum of its joined values:

    UPDATE P
    SET extrasPrice = SUM(E.price)
    FROM dbo.BookingPitchExtras AS E
    INNER JOIN dbo.BookingPitches AS P ON E.pitchID = P.ID
        AND P.bookingID = 1
    WHERE E.[required] = 1

When I run this I get the following error:

    &quot;An aggregate may not appear in the set list of an UPDATE statement.&quot;

Any ideas?

SQL Update to the SUM of its joined values

I have a list of integers and I need to count how many of them are &gt; 0.  
I&#39;m currently doing it with a list comprehension that looks like this:

    sum([1 for x in frequencies if x &gt; 0])

It seems like a decent comprehension but I don&#39;t really like the &quot;1&quot;; it seems like a bit of a magic number.  Is there a more Pythonish way to do this?  

All Sum Solutions on Gang of Coders

Total of 39 Sum Solutions