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How to find all positions of the maximum value in a list?
...iciencies pointed out by @John Machin. For (2) I attempted to optimize the tests based on guesstimated probability of occurrence of each condition and inferences allowed from predecessors. It was a little tricky figuring out the proper initialization values for max_val and max_indices which worked f...
Java LinkedHashMap get first or last entry
...import java.util.Map;
import java.util.Map.Entry;
public class PerformanceTest {
private static long startTime;
private static long endTime;
private static LinkedHashMap<Integer, String> linkedmap;
public static void main(String[] args) {
linkedmap = new LinkedHashMa...
How do I check that multiple keys are in a dict in a single pass?
... It's a good solution thanks to short-circuiting, especially if the test fails more often than not; unless you can create the set of keys of interest just once and check it many times, in which case set is superior. As usual... measure it!-)
– Alex Martelli
...
When should you use 'friend' in C++?
...
At work we use friends for testing code, extensively. It means we can provide proper encapsulation and information hiding for the main application code. But also we can have separate test code that uses friends to inspect internal state and data for te...
FFmpeg: How to split video efficiently?
...uiet -y -i input.ts -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 -sn test1.mkv
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:30:00 -t 01:00:00 -sn test2.mkv
echo "One command"
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 \
-sn...
Regular expression that matches valid IPv6 addresses
...v4-Embedded IPv6 Address)
)
I posted a script on GitHub which tests the regular expression: https://gist.github.com/syzdek/6086792
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&& (AND) and || (OR) in IF statements
...ill not be evaluated. And this is very useful. For example, if you need to test whether a String is not null or empty, you can write:
if (str != null && !str.isEmpty()) {
doSomethingWith(str.charAt(0));
}
or, the other way around
if (str == null || str.isEmpty()) {
complainAboutUnusa...
How to validate date with format “mm/dd/yyyy” in JavaScript?
...ut string is a valid date formatted as "mm/dd/yyyy"
function isValidDate(dateString)
{
// First check for the pattern
if(!/^\d{1,2}\/\d{1,2}\/\d{4}$/.test(dateString))
return false;
// Parse the date parts to integers
var parts = dateString.split("/");
var day = parseInt...
What's the difference between “Write-Host”, “Write-Output”, or “[console]::WriteLine”?
...he scenes.
Run this demonstration code and examine the result.
function Test-Output {
Write-Output "Hello World"
}
function Test-Output2 {
Write-Host "Hello World" -foreground Green
}
function Receive-Output {
process { Write-Host $_ -foreground Yellow }
}
#Output piped to another ...
Which is the preferred way to concatenate a string in Python?
...w you the timings, because it's so slow that it hasn't finished yet. These tests suddenly take minutes. Except for the append/join, which is just as fast as under later Pythons.
Yup. String concatenation was very slow in Python back in the stone age. But on 2.4 it isn't anymore (or at least Python ...