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Why does ~True result in -2?
...is not surprising if True means 1 and ~ means bitwise inversion...
...provided that
True can be treated as an integer and
integers are represented in Two's complement
Edits:
fixed the mixing between integer representation and bitwise inversion operator
applied another polishing (the shorte...
How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
...
Is HTML5 localStorage asynchronous?
...you may not have the latest elements you stored. I've tested that in a hybrid app in Android, and it makes the usage of localStorage inapropriate in some cases.
– user276648
Apr 23 '15 at 13:38
...
What is the difference between ndarray and array in numpy?
...
Still have no clue why should avoid using ndarray? Coz it's low-level?
– GabrielChu
Sep 9 '18 at 11:18
...
Read and overwrite a file in Python
...
If you don't want to close and reopen the file, to avoid race conditions, you could truncate it:
f = open(filename, 'r+')
text = f.read()
text = re.sub('foobar', 'bar', text)
f.seek(0)
f.write(text)
f.truncate()
f.close()
The functionality will likely also be cleaner and safer ...
Is it a good idea to use Google Guava library for Android development?
I am involved in the development of Android application which is a rather "thick" mobile client for a Web service. It heavily communicates with the server but also has a lot of inner logic too. So, I decided to use some features of Google Guava library to simplify development process. Here is a li...
Nested classes' scope?
...they are in a module or in a class. In the first case, a function goes outside to find the object binded to a free identifier. In the second case, a function, that is to say a method, doesn't go outside its body. Functions in a module and methods in a class are in reality two kinds of objects. Metho...
How to style the with only CSS?
...value on a combobox now remove the
dropdown button
So now in order to hide the default styling, it's as easy as adding the following rules on our select element:
select {
-webkit-appearance: none;
-moz-appearance: none;
appearance: none;
}
For IE 11 support, you can use [::-ms-expand...
Relative frequencies / proportions with dplyr
...
This seems an invalid answer on dplyr 0.7.1. It does the frequency calculation overall on "gear", instead of within each level of "am".
– Edwin
Jul 19 '17 at 14:16
...
Given an RGB value, how do I create a tint (or shade)?
... RGB. However, RGB colors specified in documents or encoded in images and video are not likely to be in linear RGB, in which case a so-called inverse transfer function needs to be applied to each of the RGB color's components. This function varies with the RGB color space. For example, in the sRGB c...