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What does ~~ (“double tilde”) do in Javascript?
I was checking out an online game physics library today and came across the ~~ operator. I know a single ~ is a bitwise NOT, would that make ~~ a NOT of a NOT, which would give back the same value, wouldn't it?
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Check image width and height before upload with Javascript
...ke it you realize this is only supported in a few browsers. Mostly firefox and chrome, could be opera as well by now.
P.S. The URL.createObjectURL() method has been removed from the MediaStream interface. This method has been deprecated in 2013 and superseded by assigning streams to HTMLMediaElemen...
How to find out which fonts are referenced and which are embedded in a PDF document
...I'd like to inspect, which fonts are actually embedded in the pdf document and which are only referenced. Is there an easy (and cheap as in free) way to do that?
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Difference between toFixed() and toPrecision()?
I'm new to JavaScript and just discovered toFixed() and toPrecision() to round numbers. However, I can't figure out what the difference between the two is.
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How to reuse an ostringstream?
I'd like to clear out and reuse an ostringstream (and the underlying buffer) so that my app doesn't have to do as many allocations. How do I reset the object to its initial state?
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Redirecting to URL in Flask
I'm new to Python and Flask and I'm trying to do the equivalent of Response.redirect as in C# - ie: redirect to a specific URL - how do I go about this?
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How can I negate the return-value of a process?
...at negates the value a process returns. It should map 0 to some value != 0 and any value != 0 to 0, i.e. the following command should return "yes, nonexistingpath doesn't exist":
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Find the max of two or more columns with pandas
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You can get the maximum like this:
>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0...
How to use if - else structure in a batch file?
I have a question about if - else structure in a batch file. Each command runs individually, but I couldn't use "if - else" blocks safely so these parts of my programme doesn't work. How can I do make these parts run? Thank you.
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java get file size efficiently
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Well, I tried to measure it up with the code below:
For runs = 1 and iterations = 1 the URL method is fastest most times followed by channel. I run this with some pause fresh about 10 times. So for one time access, using the URL is the fastest way I can think of:
LENGTH sum: 10626, per It...