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What's the recommended approach to resetting migration history using Django South?
... are taking too long, this worked for me.
rm <app-dir>/migrations/*
python manage.py schemamigration <app-name> --initial
python manage.py migrate <app-name> 0001 --fake --delete-ghost-migrations
Don't forget to manually restore any dependencies on other apps by adding lines li...
When should I use @classmethod and when def method(self)?
...atic method of java or C++. ( static method is a general term I guess ;) )
Python also has @staticmethod. and difference between classmethod and staticmethod is whether you can
access to class or static variable using argument or classname itself.
class TestMethod(object):
cls_var = 1
@clas...
differentiate null=True, blank=True in django
...: CharFields can get saved as NULL in the database (translating to None in Python) if you set null=True. The docs even say to avoid setting null=True because it allows two different kinds of "blanky" values. I just tested this behaviour with Django 1.8/MySQL 5.6
– Edward D'Souz...
How to organize large R programs?
...s top-level namespace (the one that ls() shows).
I was trying to simulate Python's system, where every file is a module. That would be better to have, but this seems OK.
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App Inventor 2 列表代码块 · App Inventor 2 中文网
...以新增额外的列表项。
可以创建混合类型的列表，类似Python等其他语言中的元组（Tuple）类型，详见《创建混合类型的列表（元组/Tuple）》。
追加列表项
将给定列表项添加到列表末尾。这个代码块是一个块...
Inserting a Link to a Webpage in an IPython Notebook
...
In case it is not a markdown cell, that is with what I went:
from IPython.core.display import display, HTML
display(HTML("""<a href="https://google.at">text</a>"""))
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How can I get the sha1 hash of a string in node.js?
...S is hashing the UTF-8 representation of the string. Other languages (like Python, PHP or PERL...) are hashing the byte string.
We can add binary argument to use the byte string.
const crypto = require("crypto");
function sha1(data) {
return crypto.createHash("sha1").update(data, "binary").dig...
What is a lambda (function)?
... nice way to write closures. With that power you can do things like this.
Python
def adder(x):
return lambda y: x + y
add5 = adder(5)
add5(1)
6
As you can see from the snippet of Python, the function adder takes in an argument x, and returns an anonymous function, or lambda, that takes anoth...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...
In Python 3.6 the fastest way is still the WouterOvermeire one. Kikohs' proposal is slower than the other two options.
import timeit
setup = '''
import pandas as pd
import numpy as np
df = pd.DataFrame(np.random.randint(32, 12...
Django - how to create a file and save it to a model's FileField?
...oring to the right spot, not creating duplicate files etc).
Django 1.4.1
Python 2.7.3
#Model
class MonthEnd(models.Model):
report = models.FileField(db_index=True, upload_to='not_used')
import csv
from os.path import join
#build and store the file
def write_csv():
path = join(settings.M...