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What is the difference between & and && in Java?
...the first operand evaluates to false since the result will be false
(x != 0) & (1/x > 1) <-- this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an exception.
(x != 0) && (1/x > 1) <-- this means evaluate (x...
How to create a density plot in matplotlib?
... [4.5]*3 + [5.5]*1 + [6.5]*8
density = gaussian_kde(data)
xs = np.linspace(0,8,200)
density.covariance_factor = lambda : .25
density._compute_covariance()
plt.plot(xs,density(xs))
plt.show()
I get
which is pretty close to what you are getting from R. What have I done? gaussian_kde uses a changa...
Why does the C# compiler go mad on this nested LINQ query?
...machine) and very long time to compile (actually I get IO exception after 10 minutes).
1 Answer
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NumPy or Pandas: Keeping array type as integer while having a NaN value
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This capability has been added to pandas (beginning with version 0.24):
https://pandas.pydata.org/pandas-docs/version/0.24/whatsnew/v0.24.0.html#optional-integer-na-support
At this point, it requires the use of extension dtype Int64 (capitalized), rather than the default dtype int64 (lowe...
Performant Entity Serialization: BSON vs MessagePack (vs JSON)
...:2} is stored in a file and you want to update the value of "a" from 1 to 2000.
With MessagePack, 1 uses only 1 byte but 2000 uses 3 bytes. So "b" must be moved backward by 2 bytes, while "b" is not modified.
With BSON, both 1 and 2000 use 5 bytes. Because of this verbosity, you don't have to move...
Looping through array and removing items, without breaking for loop
... |
edited Dec 8 '17 at 17:03
community wiki
4 r...
Javascript regex returning true.. then false.. then true.. etc [duplicate]
...
/^[^-_]([a-z0-9-_]{4,20})[^-_]$/gi;
You're using a g (global) RegExp. In JavaScript, global regexen have state: you call them (with exec, test etc.) the first time, you get the first match in a given string. Call them again and you get...
How do I check in SQLite whether a table exists?
...
1045
I missed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FR...
Positioning a div near bottom side of another div
...Chrome 1, and IE 6, 7 and 8:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html><body>
<div style='background-color: yellow; width: 70%;
height: 100px; position: relative;'>
Outer
<div...
Gradient borders
...webkit-border-image: -webkit-gradient(linear, left top, left bottom, from(#00abeb), to(#fff), color-stop(0.5, #fff), color-stop(0.5, #66cc00)) 21 30 30 21 repeat repeat;
Prooflink -- http://www.webkit.org/blog/1424/css3-gradients/
Browser support: http://caniuse.com/#search=border-image
...