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Add legend to ggplot2 line plot
...; you are creating a mapping to this "variable".
scale_colour_manual can now map these strings to the appropriate colors. The result is
In some cases, the mapping between the levels and colors needs to be made explicit by naming the values in the manual scale (thanks to @DaveRGP for pointing thi...
“On-line” (iterator) algorithms for estimating statistical median, mode, skewness, kurtosis?
...r-moment statistics.
Median
Median is tough without sorted data. If you know, how many data points you have, in theory you only have to partially sort, e.g. by using a selection algorithm. However, that doesn't help too much with billions of values. I would suggest using frequency counts, see the ...
Are global variables in PHP considered bad practice? If so, why?
...m array ($obj, 'callbackMethod') in calls to preg_replace_callback()? (I know, I've fallen prey to this OOP pitfall...)
– grossvogel
Jul 1 '10 at 16:22
24
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Possible to make labels appear when hovering over a point in matplotlib?
...the scatter plot would be unreadable if I labeled each point. Does anyone know of a way to create labels that only appear when the cursor hovers in the vicinity of that point?
...
Why does HTML5 form-validation allow emails without a dot?
...answers the 'why', not the 'solution'. I was also curious about the why. Now I know not to "fix".
– Eleanor Zimmermann
Aug 23 '16 at 20:35
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PostgreSQL function for last inserted ID
...);
SELECT currval('persons_id_seq');
The name of the sequence must be known, it's really arbitrary; in this example we assume that the table persons has an id column created with the SERIAL pseudo-type. To avoid relying on this and to feel more clean, you can use instead pg_get_serial_sequence:
...
API vs. Webservice [closed]
... I'm OK with someone objecting to my answer but I'd be curious to know why.
– Mark Biek
Apr 30 '09 at 18:46
41
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What do I need to read to understand how git works? [closed]
...t RailsConf 2008 that covers much the same ground as the book.
Said Scott now maintains http://git-scm.com/, which includes the Git community book, which is more of a usage tutorial than a technical description, but does include both a nice conceptual overview of the git data model in the introduct...
Best approach to remove time part of datetime in SQL Server
...imple-talk.com/sql/t-sql-programming/ten-common-sql-programming-mistakes/
Now, this does have an example of later SQL Server optimiser versions managing CAST to date correctly, but generally it will be a bad idea ...
Edit, Sep 2018, for datetime2
DECLARE @datetime2value datetime2 = '02180912 11:4...
How to create REST URLs without verbs?
... - when you discuss your application with end users (those who presumably know little about programming) what are the words they themselves use repeatedly?
Those are the words you should be designing your application around.
If you haven't yet had this conversion with prospective users - stop ever...