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Referring to the null object in Python
...Empty()
>>> empty==None
True
But then it also works on the empty string
>>> empty==''
True
And yet
>>> ''==None
False
>>> empty is None
False
Case 2: Using None as a boolean
The following two tests
if value:
# Do something
if not value:
# Do something
...
What are the benefits of using C# vs F# or F# vs C#? [closed]
...tter to do a UI with lots of mutable fields. Maybe he was referring to the extra overhead of having to write "mutable" and using <- instead of =.
Also depends on the library/designer used. We love using ASP.NET MVC with F# for all the controllers, then a C# web project to get the ASPX designers....
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...ta.frame(x=runif(10),y=runif(10),
grp = rep(LETTERS[1:5],each = 2),stringsAsFactors = TRUE)
#Create a custom color scale
library(RColorBrewer)
myColors <- brewer.pal(5,"Set1")
names(myColors) <- levels(dat$grp)
colScale <- scale_colour_manual(name = "grp",values = myColors)
and t...
Multiple aggregations of the same column using pandas GroupBy.agg()
...what the arguments are. As
usual, the aggregation can be a callable or a string alias.
You can now pass a tuple via keyword arguments. The tuples follow the format of (<colName>, <aggFunc>).
import pandas as pd
pd.__version__ ...
wget/curl large file from google drive
... https://drive.google.com/open?id=0B7_OwkDsUIgFWXA1B2FPQfV5S8H. Obtain the string behind the ?id= and copy it to your clipboard. That's the file's ID.
Download the file. Of course, use your file's ID instead in the following command.
gdrive download 0B7_OwkDsUIgFWXA1B2FPQfV5S8H
At first usage, t...
How can I reconcile detached HEAD with master/origin?
...nally implemented as symbolic links, but later changed to plain files with extra interpretation so that they could be used on platforms that do not have symlinks.)
We have HEAD → refs/heads/master → 17a02998078923f2d62811326d130de991d1a95a
When HEAD is detached, it points directly to a commit...
What is the meaning and difference between subject, user and principal?
...at is the benefit of breaking things down to Subject, Principal, User, its extra complexity what benefit do we get from this extra complexity?
– ams
Feb 17 '11 at 6:20
...
[精华]VC++对话框程序打印及打印预览的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ew.h”
#include “MyFrame.h”
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE［］=__FILE__;
#define new DEBUG_NEW
#endif
//////////////////////////////////////////
IMPLEMENT_DYNCREATE(CMyPreviewView, CPreviewView)
CMyPreviewView::CMyPreviewView()
{
}
CMyPreviewView::~CMyPreview...
Add centered text to the middle of a -like line
... be specified in em units. To get hr width, use (.divider width minus # of chars) / 2 .
– Kelvin
Jan 31 '13 at 22:38
13
...
How to “git show” a merge commit with combined diff output even when every changed file agrees with
...ng this on the git repository on a8e4a59 shows a combined diff (plus/minus chars in one of 2 columns). As the git-show manual mentions, it pretty much delegates to 'git diff-tree' so those options look useful.
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