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To find whether a column exists in data frame or not
...
Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
share
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How to escape a JSON string to have it in a URL?
...forum/?fromgroups=#!topic/nodejs/ivdZuGCF86Q
shows benchmarks for encoding and parsing.
Note: After testing, it looks like jsurl.js library uses ECMAScript 5 functions such as Object.keys, Array.map, and Array.filter. Therefore, it will only work on modern browsers (no ie 8 and under). However, are...
Parsing huge logfiles in Node.js - read in line-by-line
...rge files (gbs) line by line using a stream. All the third-party libraries and examples did not suit my needs since they processed the files not line by line (like 1 , 2 , 3 , 4 ..) or read the entire file to memory
The following solution can parse very large files, line by line using stream & ...
Java JTable setting Column Width
...n is null. This means that resizing has taken place "outside" the JTable
and the change - or "delta" - should be distributed to all of the columns regardless of
this JTable's automatic resize mode.
This might be why AUTO_RESIZE_LAST_COLUMN didn't help you.
Note: When a JTable makes adjust...
How might I find the largest number contained in a JavaScript array?
... edited May 22 '19 at 21:07
Andy
5,53244 gold badges3838 silver badges5252 bronze badges
answered Sep 4 '09 at 14:19
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How to connect android emulator to the internet
How can I connect my Android emulator to the internet, e.g. to use the browser? I've found lots of advice on what do to when your connected through a proxy, but that's not the case here, my machine (Windows 7) is directly connected to the router.
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Sharing src/test classes between modules in a multi-module maven project
...ensure your Data project contains all the test code that you wish to share and configure the POM to produce a test JAR:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.2</version>
<executi...
What is ModelState.IsValid valid for in ASP.NET MVC in NerdDinner?
...le if property names have been changed, migrations have not been performed and as a result the SaveChanges(); fails and cannot occur due to the change.
– Oracular Man
Feb 25 '18 at 18:46
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How to resume Fragment from BackStack if exists
...asier since it shouldn't require keeping track of a number that may change and reinforces the "unique back stack entry" logic.
Since you want only one back stack entry per Fragment, make the back state name the Fragment's class name (via getClass().getName()). Then when replacing a Fragment, use th...
Maven and adding JARs to system scope
I have a JAR in my Android project and I want it to be added to final APK.
Okay, here I go:
8 Answers
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