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What is the best way to test for an empty string in Go?
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10 Answers
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Why does changing the sum order returns a different result?
... and then rounded to the nearest representable number. Here are two sums:
1/3 + 2/3 + 2/3 = (0.3333 + 0.6667) + 0.6667
= 1.000 + 0.6667 (no rounding needed!)
= 1.667 (where 1.6667 is rounded to 1.667)
2/3 + 2/3 + 1/3 = (0.6667 + 0.6667) + 0.3333
= 1....
SQL how to increase or decrease one for a int column in one command
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To answer the first:
UPDATE Orders SET Quantity = Quantity + 1 WHERE ...
To answer the second:
There are several ways to do this. Since you did not specify a database, I will assume MySQL.
INSERT INTO table SET x=1, y=2 ON DUPLICATE KEY UPDATE x=x+1, y=y+2
REPLACE INTO table SET ...
An error occurred while installing pg (0.17.1), and Bundler cannot continue
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How can I check the size of a collection within a Django template?
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edited May 3 '17 at 6:56
MichielB
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ans...
Run Cron job every N minutes plus offset
...-59/20 * * * *
Explanation
An * in the minute field is the same as 0-59/1 where 0-59 is the range and 1 is the step. The command will run at the first minute in the range (0), then at all successive minutes that are distant from the first by step (1), until the last (59).
Which is why */20 * * *...
Android adding simple animations while setvisibility(view.Gone)
...view.animate().alpha(0.0f);
This fades it back in:
view.animate().alpha(1.0f);
This moves a View down by its height:
view.animate().translationY(view.getHeight());
This returns the View to its starting position after it has been moved somewhere else:
view.animate().translationY(0);
You ca...
Ruby replace string with captured regex pattern
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193
Try '\1' for the replacement (single quotes are important, otherwise you need to escape the \)...
How to stop Eclipse formatter from placing all enums on one line
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The answer by @wjans worked fine for normal enums, but not for enums with arguments. To expand...
How is this fibonacci-function memoized?
...is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
That is what that trick, "going-through-a-list", is exploiting. In normal doubly-recursve Fibonacci def...