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How do I check if a string is a number (float)?
... don't think that the code is perfect (but I think it's very close): it is more usual to put only the part being "tested" in the try clause, so I would put the return True in an else clause of the try. One of the reasons is that with the code in the question, if I had to review it, I would have to ...
Get MD5 hash of big files in Python
... Since you're not reading the entire file into memory, this won't use much more than 8192 bytes of memory.
In Python 3.8+ you can do
import hashlib
with open("your_filename.txt", "rb") as f:
file_hash = hashlib.md5()
while chunk := f.read(8192):
file_hash.update(chunk)
print(file_h...
Vertically align text to top within a UILabel
...abel sizeToFit];
If you have a label with longer text that will make more than one line, set numberOfLines to 0 (zero here means an unlimited number of lines).
myLabel.numberOfLines = 0;
[myLabel sizeToFit];
Longer Version
I'll make my label in code so that you can see what's g...
What is the __del__ method, How to call it?
...might not necessary happen right after and might not happen at all.
Even more, variables can live for a long time for many reasons, e.g. a propagating exception or module introspection can keep variable reference count greater than 0. Also, variable can be a part of cycle of references — CPython...
Aren't promises just callbacks?
...ite asynchronous code in a way that resembles synchronous code and is much more easy to follow:
api().then(function(result){
return api2();
}).then(function(result2){
return api3();
}).then(function(result3){
// do work
});
Certainly, not much less code, but much more readable.
But...
Is the sizeof(some pointer) always equal to four?
...ve a normal "NEAR" pointer was 16 bits and a pointer declared as "FAR" was more, probably 24, though I'm not sure.
– rmeador
Dec 29 '08 at 23:22
19
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What requirement was the tuple designed to solve?
...oup together a bunch of otherwise unrelated data in some structure that is more lightweight than a class" is useful in many, many places, not just for formal parameter lists of methods. It's useful when a method has two things to return, or when you want to key a dictionary off of two data rather th...
Viewing full output of PS command
...> (Tab can also be used to scroll right)
Lines are always wrapped for more and pg.
When ps aux is used in a pipe, the w option is unnecessary since ps only uses screen width when output is to the terminal.
share
...
do {…} while(false)
...
It's more than a disguised goto. It is a restricted (structured) goto.
– Thomas Eding
Feb 22 '10 at 20:56
...
How to estimate how much memory a Pandas' DataFrame will need?
...y_usage(index=True).sum()
731731000
Also, passing deep=True will enable a more accurate memory usage report, that accounts for the full usage of the contained objects.
This is because memory usage does not include memory consumed by elements that are not components of the array if deep=False (defau...