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Calculate the center point of multiple latitude/longitude coordinate pairs
...ing them has weird edge cases with angles when they wrap from 359' back to 0'.
A much earlier question on SO asked about finding the average of a set of compass angles.
An expansion of the approach recommended there for spherical coordinates would be:
Convert each lat/long pair into a unit-lengt...
Sleep until a specific time/date
...bash, do the following:
current_epoch=$(date +%s)
target_epoch=$(date -d '01/01/2010 12:00' +%s)
sleep_seconds=$(( $target_epoch - $current_epoch ))
sleep $sleep_seconds
To add precision down to nanoseconds (effectively more around milliseconds) use e.g. this syntax:
current_epoch=$(date +%s.%...
Hidden Features of JavaScript? [closed]
...function's arguments array-like object.
function sum() {
var retval = 0;
for (var i = 0, len = arguments.length; i < len; ++i) {
retval += arguments[i];
}
return retval;
}
sum(1, 2, 3) // returns 6
...
Histogram using gnuplot?
...x,width)=width*floor(x/width)
plot 'datafile' using (bin($1,binwidth)):(1.0) smooth freq with boxes
check out help smooth freq to see why the above makes a histogram
to deal with ranges just set the xrange variable.
share...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
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+100
I'll consider the problem of many<->one/many casemappings first and separately from handling different Normalization forms.
Fo...
How to clear the canvas for redrawing
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const context = canvas.getContext('2d');
context.clearRect(0, 0, canvas.width, canvas.height);
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What's quicker and better to determine if an array key exists in PHP?
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10 Answers
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Why does the indexing start with zero in 'C'?
...f the array is exactly contained in the memory location that array refers (0 elements away), so it should be denoted as array[0].
For more info:
http://developeronline.blogspot.com/2008/04/why-array-index-should-start-from-0.html
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Check if character is number?
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70
You could use comparison operators to see if it is in the range of digit characters:
var c = ju...
Why is printing to stdout so slow? Can it be sped up?
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I ran your file writing test on my machine, and with buffering, it also 0.05s here for 100,000 lines.
However, with the above modifications to write unbuffered, it takes 40 seconds to write only 1,000 lines to disk. I gave up waiting for 100,000 lines to write, but extrapolating from the previou...