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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 search file text for a pattern and replace it with a given value
...ull. This code is not fit for anything beyond a quick one-off script where all the data is backed up. For that reason, do NOT copy this code into your programs.
Here's a quick short way to do it.
file_names = ['foo.txt', 'bar.txt']
file_names.each do |file_name|
text = File.read(file_name)
ne...
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...
Python Create unix timestamp five minutes in the future
...
Now in Python >= 3.3 you can just call the timestamp() method to get the timestamp as a float.
import datetime
current_time = datetime.datetime.now(datetime.timezone.utc)
unix_timestamp = current_time.timestamp() # works if Python >= 3.3
unix_timestamp_pl...
Compiling Java 7 code via Maven
...
Check the mvn script in your maven installation to see how it's building the command. Perhaps you or someone else has hard-coded a JAVA_HOME in there and forgotten about it.
share
...
What are bitwise shift (bit-shift) operators and how do they work?
...hift operator, and meets the needs of both logical and arithmetic shifts.
All of these operators can be applied to integer values (int, long, possibly short and byte or char). In some languages, applying the shift operators to any datatype smaller than int automatically resizes the operand to be a...
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(...
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);
...
mysqli or PDO - what are the pros and cons? [closed]
...nvincing somebody works better with a killer feature. So there it is:
A really nice thing with PDO is you can fetch the data, injecting it automatically in an object. If you don't want to use an ORM (cause it's a just a quick script) but you do like object mapping, it's REALLY cool :
class Student...