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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...
Javascript regex returning true.. then false.. then true.. etc [duplicate]
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/^[^-_]([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 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...
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...
Looping through array and removing items, without breaking for loop
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edited Dec 8 '17 at 17:03
community wiki
4 r...
How do I check in SQLite whether a table exists?
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1045
I missed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FR...
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
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How to align absolutely positioned element to center?
... you can center an absolutely positioned element.
position:absolute;
left:0;
right:0;
margin-left:auto;
margin-right:auto;
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Calculate last day of month in JavaScript
If you provide 0 as the dayValue in Date.setFullYear you get the last day of the previous month:
20 Answers
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How to iterate a loop with index and element in Swift
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Yes. As of Swift 3.0, if you need the index for each element along with its value, you can use the enumerated() method to iterate over the array. It returns a sequence of pairs composed of the index and the value for each item in the array. For...