It was moved to &lt;a href=&quot;http://docs.python.org/py3k/library/functools.html#functools.reduce&quot;&gt;`functools`&lt;/a&gt;.

You can add

    from functools import reduce

before you use the reduce.

Or if you use the six library

    from six.moves import reduce

In this case I believe that the following is equivalent:

    l = sum([1,2,3,4]) % 2
The only problem with this is that it creates big numbers, but maybe that is better than repeated modulo operations?

you need to install and import reduce from `functools` python package

Reduce function is not defined in the Python built-in function.
So first, you should import the reduce function

    from functools import reduce

As the title of question says, is there a mustache/handlebars way of looping through an **object** properties?

So with 

    var o = {
      bob : &#39;For sure&#39;,
      roger: &#39;Unknown&#39;,
      donkey: &#39;What an ass&#39;
    }

Can I then do something *in the template engine* that would be equivalent to

    for(var prop in o)
    {
        // with say, prop a variable in the template and value the property value
    }

?

Handlebars/Mustache - Is there a built in way to loop through the properties of an object?

    #include &lt;iostream&gt;
    
    struct a {
      enum LOCAL_A { A1, A2 };
    };
    enum class b { B1, B2 };
    
    int foo(int input) { return input; }
    
    int main(void) {
      std::cout &lt;&lt; foo(a::A1) &lt;&lt; std::endl;
      std::cout &lt;&lt; foo(static_cast&lt;int&gt;(b::B2)) &lt;&lt; std::endl;
    }

The `a::LOCAL_A` is what the strongly typed enum is trying to achieve, but there is a small difference : normal enums can be converted into integer type, while strongly typed enums can not do it without a cast.

So, is there a way to convert a strongly typed enum value into an integer type without a cast? If yes, how?


How to automatically convert strongly typed enum into int?

I&#39;m using Python 3.2. Tried this:

    xor = lambda x,y: (x+y)%2
    l = reduce(xor, [1,2,3,4])
And got the following error:

    l = reduce(xor, [1,2,3,4])
    NameError: name &#39;reduce&#39; is not defined

Tried printing `reduce` into interactive console - got this error:

    NameError: name &#39;reduce&#39; is not defined

&lt;br&gt;
Is `reduce` really removed in Python 3.2? If that&#39;s the case, what&#39;s the alternative?

NameError: name &#39;reduce&#39; is not defined in Python

I'm using Python 3.2. Tried this:
<pre><code class="hljs language-ini">xor = lambda x,y: (x+y)%2
l = reduce(xor, [1,2,3,4])
</code></pre>
And got the following error:
<pre><code class="hljs language-perl">l = reduce(xor, [1,2,3,4])
NameError: name 'reduce' is not defined
</code></pre>
Tried printing <code>reduce</code> into interactive console - got this error:
<pre><code class="hljs language-csharp">NameError: name 'reduce' is not defined
</code></pre>
 
Is <code>reduce</code> really removed in Python 3.2? If that's the case, what's the alternative?

I&#39;m working with a .txt file. I want a string of the text from the file with no non-ASCII characters. However, I want to leave spaces and periods. At present, I&#39;m stripping those too. Here&#39;s the code:

    def onlyascii(char):
        if ord(char) &lt; 48 or ord(char) &gt; 127: return &#39;&#39;
        else: return char
    
    def get_my_string(file_path):
        f=open(file_path,&#39;r&#39;)
        data=f.read()
        f.close()
        filtered_data=filter(onlyascii, data)
        filtered_data = filtered_data.lower()
        return filtered_data

How should I modify onlyascii() to leave spaces and periods? I imagine it&#39;s not too complicated but I can&#39;t figure it out.

How can I remove non-ASCII characters but leave periods and spaces?

This &quot;underscoring&quot; seems to occur a lot, and I was wondering if this was a requirement in the Python language, or merely a matter of convention?

Also, could someone name and explain which functions tend to have the underscores, and why (`__init__`, for instance)?

Why do some functions have underscores &quot;__&quot; before and after the function name?

I wanted to know what is the pythonic function for this : 

I want to remove everything before the `wa` path.

    p = path.split(&#39;/&#39;)
    counter = 0
    while True:
        if p[counter] == &#39;wa&#39;:
            break
        counter += 1
    path = &#39;/&#39;+&#39;/&#39;.join(p[counter:])

For instance, I want `&#39;/book/html/wa/foo/bar/&#39;` to become `&#39;/wa/foo/bar/&#39;`.

How to remove a path prefix in python?

So, i have a file models.py in MyApp folder:
    
    from django.db import models
    class Model_One(models.Model):
        ...
    class Model_Two(models.Model):
        ...
    ...
It can be about 10-15 classes.
**How to find all models in the MyApp and get their names?** 

Since models are not iterable, I don&#39;t know if this is even possible.

Django get list of models in application

I already extract some information from a forum. It is the raw string I have now:

    string = &#39;i think mabe 124 + &lt;font color=&quot;black&quot;&gt;&lt;font face=&quot;Times New Roman&quot;&gt;but I don\&#39;t have a big experience it just how I see it in my eyes &lt;font color=&quot;green&quot;&gt;&lt;font face=&quot;Arial&quot;&gt;fun stuff&#39;

The thing I do not like is the sub string `&quot;&lt;font color=&quot;black&quot;&gt;&lt;font face=&quot;Times New Roman&quot;&gt;&quot;` and `&quot;&lt;font color=&quot;green&quot;&gt;&lt;font face=&quot;Arial&quot;&gt;&quot;`. I do want to keep the other part of string except this. So the result should be like this

    resultString = &quot;i think mabe 124 + but I don&#39;t have a big experience it just how I see it in my eyes fun stuff&quot;


How could I do this? Actually I used beautiful soup to extract the string above from a forum. Now I may prefer regular expression to remove the &lt;font *&gt; part.

Remove Sub String by using Python

I have to find the average of a list in Python. This is my code so far

    from functools import reduce

    l = [15, 18, 2, 36, 12, 78, 5, 6, 9]
    print(reduce(lambda x, y: x + y, l))

I&#39;ve got it so it adds together the values in the list, but I don&#39;t know how to make it divide into them?

Finding the average of a list

Trying to learn F# but got confused when trying to distinguish between [fold][1] and [reduce][2]. Fold seems to do the [same thing][3] but takes an extra parameter. Is there a legitimate reason for these two functions to exist or they are there to accommodate people with different backgrounds? (E.g.: String and string in C#)

Here is code snippet copied from sample:

    let sumAList list =
        List.reduce (fun acc elem -&gt; acc + elem) list

    let sumAFoldingList list =
        List.fold (fun acc elem -&gt; acc + elem) 0 list

    printfn &quot;Are these two the same? %A &quot; 
                 (sumAList [2; 4; 10] = sumAFoldingList [2; 4; 10])

  [1]: http://msdn.microsoft.com/en-us/library/ee353894.aspx
  [2]: http://msdn.microsoft.com/en-us/library/ee370239.aspx
  [3]: https://stackoverflow.com/questions/3682371/accumulate-vs-fold-vs-reduce-vs-compress

Difference between fold and reduce?

What is the most idiomatic way to achieve something like the following, in Haskell:

    foldl (+) 0 [1,2,3,4,5]
    --&gt; 15

Or its equivalent in Ruby:

    [1,2,3,4,5].inject(0) {|m,x| m + x}
    #&gt; 15

Obviously, Python provides the `reduce` function, which is an implementation of fold, exactly as above, however, I was told that the &#39;pythonic&#39; way of programming was to avoid `lambda` terms and higher-order functions, preferring list-comprehensions where possible. Therefore, is there a preferred way of folding a list, or list-like structure in Python that isn&#39;t the `reduce` function, or is `reduce` the idiomatic way of achieving this?



What is the &#39;pythonic&#39; equivalent to the &#39;fold&#39; function from functional programming?

In Hadoop when do reduce tasks start? Do they start after a certain percentage (threshold) of mappers complete? If so, is this threshold fixed? What kind of threshold is typically used?

When do reduce tasks start in Hadoop?

`filter`, `map`, and `reduce` work perfectly in Python 2. Here is an example:

    &gt;&gt;&gt; def f(x):
            return x % 2 != 0 and x % 3 != 0
    &gt;&gt;&gt; filter(f, range(2, 25))
    [5, 7, 11, 13, 17, 19, 23]

    &gt;&gt;&gt; def cube(x):
            return x*x*x
    &gt;&gt;&gt; map(cube, range(1, 11))
    [1, 8, 27, 64, 125, 216, 343, 512, 729, 1000]

    &gt;&gt;&gt; def add(x,y):
            return x+y
    &gt;&gt;&gt; reduce(add, range(1, 11))
    55

But in Python 3, I receive the following outputs:

    &gt;&gt;&gt; filter(f, range(2, 25))
    &lt;filter object at 0x0000000002C14908&gt;

    &gt;&gt;&gt; map(cube, range(1, 11))
    &lt;map object at 0x0000000002C82B70&gt;

    &gt;&gt;&gt; reduce(add, range(1, 11))
    Traceback (most recent call last):
      File &quot;&lt;pyshell#8&gt;&quot;, line 1, in &lt;module&gt;
        reduce(add, range(1, 11))
    NameError: name &#39;reduce&#39; is not defined

I would appreciate if someone could explain to me why this is.

Screenshot of code for further clarity:

[![IDLE sessions of Python 2 and 3 side-by-side](http://i.imgur.com/WekeD.png)](http://i.imgur.com/WekeD.png)

Content Type	Original Author	Original Content on Stackoverflow
Question	Sergey	View Question on Stackoverflow
Solution 1 - Python	Ignacio Vazquez-Abrams	View Answer on Stackoverflow
Solution 2 - Python	3heveryday	View Answer on Stackoverflow
Solution 3 - Python	Azd325	View Answer on Stackoverflow
Solution 4 - Python	David M	View Answer on Stackoverflow
Solution 5 - Python	Jesvin Vijesh S	View Answer on Stackoverflow
Solution 6 - Python	Haroon Hayat	View Answer on Stackoverflow

NameError: name 'reduce' is not defined in Python

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How to automatically convert strongly typed enum into int?

Handlebars/Mustache - Is there a built in way to loop through the properties of an object?

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