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Convert python datetime to epoch with strftime
I have a time in UTC from which I want the number of seconds since epoch.
8 Answers
8
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Why use String.Format? [duplicate]
...nd uses less overhead. Using concat +/& has to rebuild the string each time which can be very bad in large string objects. The very definition of a string is that it should be defined once and reused many times.(Many books teach us to use concat as examples but never tell us about performance!!)...
C++ performance challenge: integer to std::string conversion
...d::string. By changing just one line of code the function runs in half the time on my machine, using GCC. And by removing the std::string people would be able to use this function inside C programs.
– user1593842
May 4 at 22:35
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Measuring execution time of a function in C++
I want to find out how much time a certain function takes in my C++ program to execute on Linux . Afterwards, I want to make a speed comparison . I saw several time function but ended up with this from boost. Chrono:
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Canvas width and height in HTML5
...st ctx = document.querySelector("#c").getContext("2d");
function render(time) {
time *= 0.001;
resizeCanvasToDisplaySize(ctx.canvas);
ctx.fillStyle = "#DDE";
ctx.fillRect(0, 0, ctx.canvas.width, ctx.canvas.height);
ctx.save();
const spacing = 64;
const size = 48;
con...
Delete files older than 10 days using shell script in Unix [duplicate]
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find is the common tool for this kind of task :
find ./my_dir -mtime +10 -type f -delete
EXPLANATIONS
./my_dir your directory (replace with your own)
-mtime +10 older than 10 days
-type f only files
-delete no surprise. Remove it to test your find filter before executing the whole com...
Regular expression to stop at first match
...ult, a quantified subpattern is "greedy", that is, it will
match as many times as possible (given a particular starting location)
while still allowing the rest of the pattern to match. If you want it
to match the minimum number of times possible, follow the quantifier
with a "?" . Note that ...
Downcasting in Java
...Downcasting is allowed when there is a possibility that it succeeds at run time:
Object o = getSomeObject(),
String s = (String) o; // this is allowed because o could reference a String
In some cases this will not succeed:
Object o = new Object();
String s = (String) o; // this will fail at runt...
How do I get the row count of a pandas DataFrame?
... len(df.index) takes 381 nanoseconds, or 0.381 microseconds, df.shape is 3 times slower, taking 1.17 microseconds. did I miss something? @root
– T.G.
May 22 '17 at 18:34
11
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Alternate output format for psql
... that selecting all columns causes a row of query results to wrap multiple times. Consequently, the output is hard to read.
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