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How can I cast int to enum?
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@FlySwat, what if YourEnum is dynamic and will only be known at runtime, and what I want is to convert to Enum?
– Shimmy Weitzhandler
Feb 19 '12 at 9:56
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Remove NA values from a vector
I have a huge vector which has a couple of NA values, and I'm trying to find the max value in that vector (the vector is all numbers), but I can't do this because of the NA values.
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Change the default editor for files opened in the terminal? (e.g. set it to TextEdit/Coda/Textmate)
...tions/TextEdit.app/Contents/MacOS/TextEdit"
or just type the following command into your Terminal:
echo "export EDITOR=\"/Applications/TextEdit.app/Contents/MacOS/TextEdit\"" >> ~/.bashrc
If you are using zsh, use ~/.zshrc instead of ~/.bashrc.
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Most efficient way to prepend a value to an array
... Only one issue with this solution. Doesn't unshift() return its length, and not the array as in this answer? w3schools.com/jsref/jsref_unshift.asp
– iDVB
Mar 8 '15 at 5:36
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What is WebKit and how is it related to CSS?
...ring engine for Safari/Chrome. Are there such engines for IE/Opera/Firefox and what are the differences, pros and cons of using one over the other? Can I use WebKit features in Firefox for example?
Every browser is backed by a rendering engine to draw the HTML/CSS web page.
IE → Trident (disco...
Get nth character of a string in Swift programming language
...tion: Please see Leo Dabus' answer for a proper implementation for Swift 4 and Swift 5.
Swift 4 or later
The Substring type was introduced in Swift 4 to make substrings
faster and more efficient by sharing storage with the original string, so that's what the subscript functions should return.
Try...
How to append rows to an R data frame
...rs of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n)...
Intersection and union of ArrayLists in Java
...ut using any third-party library. Main advantage over retainAll, removeAll and addAll is that these methods don't modify the original lists input to the methods.
public class Test {
public static void main(String... args) throws Exception {
List<String> list1 = new ArrayList<...
Drop all tables whose names begin with a certain string
...his script several times because of foreign key constraints between master and detail tables.
– Alexander Prokofyev
Dec 26 '08 at 5:24
7
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SVN upgrade working copy
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You have to upgrade your subversion client to at least 1.7.
With the command line client, you have to manually upgrade your working copy format by issuing the command svn upgrade:
Upgrading the Working Copy
Subversion 1.7 introduces substantial changes to the working copy
format. In pre...