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How to access the ith column of a NumPy multidimensional array?
...,
[3, 4],
[5, 6]])
As you already know from other answers, to get it in the form of "row vector" (array of shape (3,)), you use slicing:
arr_c1_ref = arr[:, 1] # creates a reference to the 1st column of the arr
arr_c1_copy = arr[:, 1].copy() # creates a cop...
Is “Java Concurrency In Practice” still valid? [closed]
...ersions of Java than new versions of the book, so I'm focusing on that for now. Maybe after Project Loom delivers, it'll be different.
– Brian Goetz
Dec 7 '18 at 15:19
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Android Fragment no view found for ID?
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@howettl: I know it is bit old post. But I am not able fix this issue with your answer. Here is SO question: stackoverflow.com/questions/25844394/… - Can you help me with this please? Thanks!
– TheDevMan
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quick random row selection in Postgres
...e optimal solution if you want only one row selected, because you need to know the COUNT of the table to calculate the exact percentage.
To avoid a slow COUNT and use fast TABLESAMPLE for tables from 1 row to billions of rows, you can do:
SELECT * FROM my_table TABLESAMPLE SYSTEM(0.000001) LIMI...
When is the @JsonProperty property used and what is it used for?
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well for what its worth now... JsonProperty is ALSO used to specify getter and setter methods for the variable apart from usual serialization and deserialization. For example suppose you have a payload like this:
{
"check": true
}
and a Deseria...
Sqlite or MySql? How to decide? [closed]
...r an Athlon 1600. 1GB RAM. 5400RPM IDE disk. Redhat 7.3. He concludes: «I now believe that SQLite is appropriate for use as the primary database on websites that get up to 1 million hits per day.»
– Rutrus
Dec 27 '16 at 0:45
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C# '@' before a String [duplicate]
...pe it. I always hated not being able to escape " when using @. I feel dumb now. Thanks...
– Dustin Davis
Feb 2 '11 at 21:59
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What is the difference between pylab and pyplot? [duplicate]
...This wording is no longer in the documentation.
Use of the pylab import is now discouraged and the OO interface is recommended for most non-interactive usage.
From the documentation, the emphasis is mine:
Matplotlib is the whole package; pylab is a module in matplotlib that gets installed alongsid...
How to check postgres user and password? [closed]
A friend of mine done this config on my mac. But I don't know the username and password he had chosen.
2 Answers
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How to copy JavaScript object to new variable NOT by reference? [duplicate]
...ATE 2017: I should mention, since this is a popular answer, that there are now better ways to achieve this using newer versions of javascript:
In ES6 or TypeScript (2.1+):
var shallowCopy = { ...oldObject };
var shallowCopyWithExtraProp = { ...oldObject, extraProp: "abc" };
Note that if extraPr...