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How to append rows to an R data frame
...<- function(n){
df <- data.frame(x = numeric(n), y = character(n), stringsAsFactors = FALSE)
for(i in 1:n){
df$x[i] <- i
df$y[i] <- toString(i)
}
df
}
Here's a similar approach, but one where the data.frame is created as the last step.
# Use preallocated vectors
f4 <...
Remove HTML Tags in Javascript with Regex
I am trying to remove all the html tags out of a string in Javascript.
Heres what I have... I can't figure out why its not working....any know what I am doing wrong?
...
Changing variable names in Vim
...nvar()
expand("<cword>") gets the word under the cursor. The search string uses % for file-scope, and the \(\W\) patterns look for non-word characters at the boundary of the word to replace, and save them in variables \1 and \2 so as to be re-inserted in the replacement pattern.
...
What is the advantage to using bloom filters?
... bits, for small integers, to an
arbitrary number of bits, such as for
strings (tries are an exception, since
they can share storage between
elements with equal prefixes). Linked
structures incur an additional linear
space overhead for pointers. A Bloom
filter with 1% error and an opti...
How to strip all whitespace from string
How do I strip all the spaces in a python string? For example, I want a string like strip my spaces to be turned into stripmyspaces , but I cannot seem to accomplish that with strip() :
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Replace one substring for another string in shell script
...
To replace the first occurrence of a pattern with a given string, use ${parameter/pattern/string}:
#!/bin/bash
firstString="I love Suzi and Marry"
secondString="Sara"
echo "${firstString/Suzi/$secondString}"
# prints 'I love Sara and Marry'
To replace all occurrences, use ${p...
How to handle Handler messages when activity/fragment is paused
... 1;
final static class State extends Fragment {
static final String TAG = "State";
/**
* Handler for this activity
*/
public ConcreteTestHandler handler = new ConcreteTestHandler();
@Override
public void onCreate(Bundle savedInstanceSt...
Convert a string to an enum in C#
What's the best way to convert a string to an enumeration value in C#?
25 Answers
25
...
Boolean vs boolean in Java
... Booleans, conditional operators and autoboxing):
public static void main(String[] args) throws Exception {
Boolean b = true ? returnsNull() : false; // NPE on this line.
System.out.println(b);
}
public static Boolean returnsNull() {
return null;
}
Use Boolean when you need an object, e...
Sort NSArray of date strings or objects
I have an NSArray that contains date strings (i.e. NSString) like this: "Thu, 21 May 09 19:10:09 -0700"
9 Answers
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