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vector::at vs. vector::operator[]
...bugs in your code. If you need to bounds-check at runtime because e.g. the index comes from user input, you're indeed best off with an if statement. So in summary, design your code with the intention that vector::at() will never throw an exception, so that if it does, and your program aborts, it's a...
How can I set the value of a DropDownList using jQuery?
...
If you working with index you can set the selected index directly with .attr():
$("#mydropdownlist").attr('selectedIndex', 0);
This will set it to the first value in the droplist.
Edit:
The way I did it above used to work. But it seems like ...
Replace all spaces in a string with '+' [duplicate]
...ll(Source, stringToFind, stringToReplace) {
var temp = Source;
var index = temp.indexOf(stringToFind);
while (index != -1) {
temp = temp.replace(stringToFind, stringToReplace);
index = temp.indexOf(stringToFind);
}
return temp;
}
String.prototype.ReplaceAll = f...
Creating a new column based on if-elif-else condition
...B'], 'C'] = 1
df.loc[df['A'] < df['B'], 'C'] = -1
Easy to solve using indexing. The first line of code reads like so, if column A is equal to column B then create and set column C equal to 0.
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...p being the effective maximum if you want to use UTF-8 and have the column indexed (because of index length limitations).
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How can I get a java.io.InputStream from a java.lang.String?
... private final Writer encoder;
private final String data;
private int index;
public StringInputStream(String sequence, Charset charset) {
data = sequence;
encoder = new OutputStreamWriter(
new OutputStreamBuffer(), charset);
}
private int buffer() throws IOException {
...
Algorithm to return all combinations of k elements from n
...hm 382: Combinations of M out of N Objects' (1970)
The algorithm in C...
Index of Combinations in Lexicographical Order (Buckles Algorithm 515)
You can also reference a combination by its index (in lexicographical order). Realizing that the index should be some amount of change from right to lef...
Using DNS to redirect to another URL with a path [closed]
... subdomains, so instead of:
www.proof.com IN CNAME www.proof-two.com/path/index.htm
You could use:
www.proof.com IN CNAME proof.proof-two.com
then go to wherever you host proof-two.com and set it to point proof.proof-two.com to www.proof-two.com/path/index.htm.
~ there's always more than one wa...
String's Maximum length in Java - calling length() method
..., which is 2^31 - 1 (or approximately 2 billion.)
In terms of lengths and indexing of arrays, (such as char[], which is probably the way the internal data representation is implemented for Strings), Chapter 10: Arrays of The Java Language Specification, Java SE 7 Edition says the following:
The...
schema builder laravel migrations unique on two columns
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The second param is to manually set the name of the unique index. Use an array as the first param to create a unique key across multiple columns.
$table->unique(array('mytext', 'user_id'));
or (a little neater)
$table->unique(['mytext', 'user_id']);
...