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How to append contents of multiple files into one file
... should be >> right ? and also why is there a newline before all the text in my 0.txt file ?
– Steam
Aug 2 '13 at 0:00
2
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How to parse/read a YAML file into a Python object? [duplicate]
...ame: Node 2
branch2-1:
name: Node 2-1
And you've installed PyYAML like this:
pip install PyYAML
And the Python code looks like this:
import yaml
with open('tree.yaml') as f:
# use safe_load instead load
dataMap = yaml.safe_load(f)
The variable dataMap now contains...
When saving, how can you check if a field has changed?
...
Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
What are the most common naming conventions in C?
...I follow the GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_p...
What's the pythonic way to use getters and setters?
...
Try this: Python Property
The sample code is:
class C(object):
def __init__(self):
self._x = None
@property
def x(self):
"""I'm the 'x' property."""
print("getter of x called")
return self._x
@x.setter
def x(self, value):
print("sette...
How to remove files that are listed in the .gitignore but still on the repository?
...
You can remove them from the repository manually:
git rm --cached file1 file2 dir/file3
Or, if you have a lot of files:
git rm --cached `git ls-files -i --exclude-from=.gitignore`
But this doesn't seem to work in Git Bash on Windows. It produces an error messag...
What's “P=NP?”, and why is it such a famous question? [closed]
The question of whether P=NP is perhaps the most famous in all of Computer Science. What does it mean? And why is it so interesting?
...
How to display pandas DataFrame of floats using a format string for columns?
...
As of Pandas 0.17 there is now a styling system which essentially provides formatted views of a DataFrame using Python format strings:
import pandas as pd
import numpy as np
constants = pd.DataFrame([('pi',np.pi),('e',np.e)],
columns=['name','value'])
C = constants...
How do I add a placeholder on a CharField in Django?
...
Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
How can I measure the speed of code written in PHP? [closed]
How can I say which class of many (which all do the same job) execute faster? is there a software to measure that?
10 Answe...