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Can I query MongoDB ObjectId by date?
...Seconds + "0000000000000000");
return constructedObjectId
}
/* Find all documents created after midnight on May 25th, 1980 */
db.mycollection.find({ _id: { $gt: objectIdWithTimestamp('1980/05/25') } });
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How to avoid annoying error “declared and not used”
...s it easier to read code written by other people (you are always sure that all declared variables will be used), and avoid some possible dead code.
But, if you really want to skip this error, you can use the blank identifier (_) :
package main
import (
"fmt" // imported and not used: "fmt"
)
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How to deal with floating point number precision in JavaScript?
...at depends on what kind of
calculations you’re doing.
If you really need your results to add up exactly, especially when you
work with money: use a special decimal
datatype.
If you just don’t want to see all those extra decimal places: simply
format your result rounded to a fix...
maximum value of int
...imum value. Same goes for the C macros/constants.
– dalle
Dec 31 '09 at 11:29
4
in C99 you can al...
Pandas conditional creation of a series/dataframe column
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List comprehension is another way to create another column conditionally. If you are working with object dtypes in columns, like in your example, list comprehensions typically outperform most other methods.
Example list comprehension:
df['color'] = ['red' if x == 'Z' else 'green' for x in d...
MySQL Results as comma separated list
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The intent is fine and MySQL will allow this, but be careful (generally) with your use of GROUP BY. The items in the select list need to be valid aggregates in the context of the GROUP BY clause. In this case, p.name is not strictly valid. Any database con...
When do I use the PHP constant “PHP_EOL”?
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@Andre: How about anyone that writes apps to be installed, used and deployed by others? Are you suggesting these should all limit their "supported platforms" to *nix?
– Cylindric
Mar 4 '11 at 10:52
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git log of a single revision
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That will give you the commit log, and then you'll have full control over all the git logging options for your automation purposes. In your instance you said you wanted the change-set. The most human-readable way to accomplish that would be:
git log --name-status --diff-filter="[A|C|D|M|R|T]" -1 -...
Convert SVG image to PNG with PHP
I'm working on a web project that involves a dynamically generated map of the US coloring different states based on a set of data.
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Alternatives to gprof [closed]
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Valgrind has an instruction-count profiler with a very nice visualizer called KCacheGrind. As Mike Dunlavey recommends, Valgrind counts the fraction of instructions for which a procedure is live on the stack, although I'm sorry to say it appears to become confused in the presence of mutual recur...