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Python date string to date object
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edited Aug 1 '19 at 21:52
Alan W. Smith
20.7k33 gold badges6060 silver badges8484 bronze badges
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Pandas percentage of total with groupby
...impler way -- just groupby the state_office and divide the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1...
How to convert ActiveRecord results into an array of hashes
... use as_json method which converts ActiveRecord objects to Ruby Hashes despite its name
tasks_records = TaskStoreStatus.all
tasks_records = tasks_records.as_json
# You can now add new records and return the result as json by calling `to_json`
tasks_records << TaskStoreStatus.last.as_json
ta...
How do you serialize a model instance in Django?
... object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
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Iterate over the lines of a string
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Here are three possibilities:
foo = """
this is
a multi-line string.
"""
def f1(foo=foo): return iter(foo.splitlines())
def f2(foo=foo):
retval = ''
for char in foo:
retval += char if not char == '\n' else ''
if char == ...
Rename specific column(s) in pandas
...ta.rename(columns={'gdp':'log(gdp)'}, inplace=True)
The rename show that it accepts a dict as a param for columns so you just pass a dict with a single entry.
Also see related
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How to get function parameter names/values dynamically?
.../d){}) // returns ['a','d']
getParamNames(function (){}) // returns []
Edit:
With the invent of ES6 this function can be tripped up by default parameters. Here is a quick hack which should work in most cases:
var STRIP_COMMENTS = /(\/\/.*$)|(\/\*[\s\S]*?\*\/)|(\s*=[^,\)]*(('(?:\\'|[^'\r\n])*')|...
e.printStackTrace equivalent in python
...ava's e.printStackTrace() that exactly traces the exception to what line it occurred and prints the entire trace of it.
4...
How to declare a global variable in php?
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If you have a set of functions that need some common variables, a class with properties may be a good choice instead of a global:
class MyTest
{
protected $a;
public function __construct($a)
{
$this->a = $a;
}
public function head()
{
echo $this->a;...
Understanding the map function
Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
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