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Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
...
How to reset sequence in postgres and fill id column with new data?
... This might cause duplicate ids. To prevent this, you can first set all to very high values: UPDATE t SET idcolumn=1000000+ nextval('seq'); then run the above script.
– tahagh
Nov 28 '13 at 13:15
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(-2147483648> 0) returns true in C++?
-2147483648 is the smallest integer for integer type with 32 bits, but it seems that it will overflow in the if(...) sentence:
...
Reading header data in Ruby on Rails
..."Cookie"]
New way:
request.headers["HTTP_COOKIE"]
To get a Hash with all headers of the request.
request.headers
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How can I programmatically determine if my app is running in the iphone simulator?
...er "Compiling source code conditionally"
The relevant definition is TARGET_OS_SIMULATOR, which is defined in /usr/include/TargetConditionals.h within the iOS framework. On earlier versions of the toolchain, you had to write:
#include "TargetConditionals.h"
but this is no longer necessary on the ...
Min/Max of dates in an array?
...
_.min and _.max work on arrays of dates; use those if you're using Lodash or Underscore, and consider using Lodash (which provides many utility functions like these) if you're not already.
For example,
_.min([
new Date(...
HTTP authentication logout via PHP
...ecification (section 15.6):
Existing HTTP clients and user agents typically retain authentication
information indefinitely. HTTP/1.1. does not provide a method for a
server to direct clients to discard these cached credentials.
On the other hand, section 10.4.2 says:
If the request...
Tool to convert Python code to be PEP8 compliant
...fficult
As an alternative (and thanks to @y-p for the idea), I wrote a small package which autopep8s only those lines which you have been working on since the last commit/branch:
Basically leaving the project a little better than you found it:
pip install pep8radius
Suppose you've done your wo...
Base 64 encode and decode example code
...Charsets:
// Sending side
byte[] data = text.getBytes(StandardCharsets.UTF_8);
String base64 = Base64.encodeToString(data, Base64.DEFAULT);
// Receiving side
byte[] data = Base64.decode(base64, Base64.DEFAULT);
String text = new String(data, StandardCharsets.UTF_8);
...
Trying to understand CMTime and CMTimeMake
...llowing code makes the concept more clear:
1)
Float64 seconds = 5;
int32_t preferredTimeScale = 600;
CMTime inTime = CMTimeMakeWithSeconds(seconds, preferredTimeScale);
CMTimeShow(inTime);
The above code gives:
{3000/600 = 5.000}
Which means a total duration of 5 seconds, with 3000 frames with...