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How to raise a ValueError?
...od named __contains__() that does something a little different, membership-testing-wise.
def contains(char_string, char):
largest_index = -1
for i, ch in enumerate(char_string):
if ch == char:
largest_index = i
if largest_index > -1: # any found?
return l...
How JavaScript closures are garbage collected
...le above the GC has no way of knowing if the variable is used or not (code tested and works in Chrome30, FF25, Opera 12 and IE10).
The memory is released if the reference to the object is broken by assigning another value to window.f_.
In my opinion this isn't a bug.
...
Does Java have something like C#'s ref and out keywords?
...ing:
void changeString( _<String> str ) {
str.s("def");
}
void testRef() {
_<String> abc = new _<String>("abc");
changeString( abc );
out.println( abc ); // prints def
}
Out
void setString( _<String> ref ) {
str.s( "def" );
}
void testOut(){
_&...
Using i and j as variables in Matlab
...mpiled version of Matlab? I have never found it to be the case (and simple tests calling a for loop 1 billion times show no statistical difference in timing). For all we know there is special code to handle exactly this and using variables other than i and j (and k?) is actually slightly slower. And...
What is the Git equivalent for revision number?
...evision for re-acquiring the code? Suppose "revision 68" is released to a testing environment, development continues, and later a developer needs to re-acquire "revision 68" from source control. How would he target the specific version to clone? Or am I missing something about Git that makes this...
Two single-column indexes vs one two-column index in MySQL?
...
"MySQL can use multiple-column indexes for queries that test all the columns in the index, or queries that test just the first column, the first two columns, the first three columns, and so on. If you specify the columns in the right order in the index definition, a single composi...
In-Place Radix Sort
...should be fast.
Edit:
I got curious whether this code actually works, so I tested/debugged it while waiting for my own bioinformatics code to run. The version above now is actually tested and works. For 10 million sequences of 5 bases each, it's about 3x faster than an optimized introsort.
...
How can you find the height of text on an HTML canvas?
...t, descent and height (which is just ascent + descent for convenience). To test it, it's worth having a function that draws a horizontal line:
var testLine = function(ctx, x, y, len, style) {
ctx.strokeStyle = style;
ctx.beginPath();
ctx.moveTo(x, y);
ctx.lineTo(x + len, y);
ctx.closePat...
Java 8 Streams - collect vs reduce
...Salary);
}
public Integer getSalary(){
return this.salary;
}
}
@Test
public void testReduceWithImmutable(){
List<Employee> list = new LinkedList<>();
list.add(new Employee("1"));
list.add(new Employee("2"));
list.add(new Employee("3"));
Integer sum = list
.stream(...
Is this a “good enough” random algorithm; why isn't it used if it's faster?
...ckage com.stackoverflow.q14491966;
import java.util.Arrays;
public class Test {
public static void main(String[] args) throws Exception {
QuickRandom qr = new QuickRandom();
int[] frequencies = new int[10];
for (int i = 0; i < 100000; i++) {
frequencies[...