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Deleting array elements in JavaScript - delete vs splice
... myArray = ['a', 'b', 'c', 'd']
["a", "b", "c", "d"]
> delete myArray[0]
true
> myArray[0]
undefined
Note that it is not in fact set to the value undefined, rather the property is removed from the array, making it appear undefined. The Chrome dev tools make this distinction clear by pr...
Pandas aggregate count distinct
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How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id...
enum - getting value of enum on string conversion
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edited Jun 30 '14 at 10:16
answered Jun 30 '14 at 10:01
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How to increment a pointer address and pointer's value?
...else?
– felipemaia
Nov 21 '11 at 15:03
@Lundin Hi, is the answer above corrected now? Thanks.
– ...
Update multiple rows in same query using PostgreSQL
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+50
You can also use update ... from syntax and use a mapping table. If you want to update more than one column, it's much more generaliza...
Python OpenCV2 (cv2) wrapper to get image size?
... width, channels = img.shape
>>> print height, width, channels
600 800 3
In case you were working with binary images, img will have two dimensions, and therefore you must change the code to: height, width = img.shape
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Stubbing a class method with Sinon.js
...ensor.prototype.
sinon.stub(Sensor, "sample_pressure", function() {return 0})
is essentially the same as this:
Sensor["sample_pressure"] = function() {return 0};
but it is smart enough to see that Sensor["sample_pressure"] doesn't exist.
So what you would want to do is something like these:
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How to loop backwards in python? [duplicate]
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302
range() and xrange() take a third parameter that specifies a step. So you can do the following....
Aligning a float:left div to center?
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clairesuzyclairesuzy
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Convert Linq Query Result to Dictionary
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edited Mar 18 '19 at 19:50
community wiki
3 re...