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Python dictionary: Get list of values for list of keys
...n list-comp:
Build list and throw exception if key not found: map(mydict.__getitem__, mykeys)
Build list with None if key not found: map(mydict.get, mykeys)
Alternatively, using operator.itemgetter can return a tuple:
from operator import itemgetter
myvalues = itemgetter(*mykeys)(mydict)
# use ...
Does MongoDB's $in clause guarantee order
...ly have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
db.collection.aggregate([
// Match the selected documents by "_id"
...
Meaning of @classmethod and @staticmethod for beginner? [duplicate]
...thod can have no parameters at all.
Example
class Date(object):
def __init__(self, day=0, month=0, year=0):
self.day = day
self.month = month
self.year = year
@classmethod
def from_string(cls, date_as_string):
day, month, year = map(int, date_as_string...
Dealing with commas in a CSV file
....Read ) )
{
}
public CsvReader( Stream stream )
{
__reader = new StreamReader( stream );
}
public System.Collections.IEnumerable RowEnumerator
{
get {
if ( null == __reader )
throw new System.ApplicationException( "I can't sta...
How to pretty print nested dictionaries?
...ues in Py2, it's cause it can't handle Unicode properly without hacks like __future__ that the answer now mentions, so you have to employ those wherever needed (or update to 3 already).
– sudo
Feb 14 '18 at 18:10
...
Convert json data to a html table [closed]
...in vanilla-js, using DOM methods to prevent html injection.
Demo
var _table_ = document.createElement('table'),
_tr_ = document.createElement('tr'),
_th_ = document.createElement('th'),
_td_ = document.createElement('td');
// Builds the HTML Table out of myList json data from Ivy r...
Callback functions in C++
...ard algorithms library <algorithm> use callbacks. For example the for_each algorithm applies an unary callback to every item in a range of iterators:
template<class InputIt, class UnaryFunction>
UnaryFunction for_each(InputIt first, InputIt last, UnaryFunction f)
{
for (; first != las...
C#: Printing all properties of an object [duplicate]
...
@Best_Where_Gives - So you could extend the code to handle this, at engineforce has done. Sometimes you've got to write a bit of code yourself..!
– Sean
Feb 7 '18 at 9:14
...
Call a python function from jinja2
...
For those using Flask, put this in your __init__.py:
def clever_function():
return u'HELLO'
app.jinja_env.globals.update(clever_function=clever_function)
and in your template call it with {{ clever_function() }}
...
Get the _id of inserted document in Mongo database in NodeJS
...ection.insert that will return the doc or docs inserted, which should have _ids.
Try:
collection.insert(objectToInsert, function(err,docsInserted){
console.log(docsInserted);
});
and check the console to see what I mean.
...