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Checking if a string can be converted to float in Python
...False
print(isfloat("12.34.56")) False Two dots not allowed.
print(isfloat("#56")) False
print(isfloat("56%")) False
print(isfloat("0E0")) True
print(isfloat("x86E0")) False
print(isfloat("86-5")) ...
How to implement an ordered, default dict? [duplicate]
...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
...
Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...;> s1 = s.decode('utf-8')
>>> print s1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-5: ordinal not in range(128)
>>>
Consult the docs for your linux variant to disc...
How to remove illegal characters from path and filenames?
...gal path into a legitimate but probably unintended one.
Edit: Or a potentially 'better' solution, using Regex's.
string illegal = "\"M\"\\a/ry/ h**ad:>> a\\/:*?\"| li*tt|le|| la\"mb.?";
string regexSearch = new string(Path.GetInvalidFileNameChars()) + new string(Path.GetInvalidPathChars());
...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...
Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardwa...
How to easily map c++ enums to strings
...xtra syntactic sugar, here's how to write a map_init class. The goal is to allow
std::map<MyEnum, const char*> MyMap;
map_init(MyMap)
(eValue1, "A")
(eValue2, "B")
(eValue3, "C")
;
The function template <typename T> map_init(T&) returns a map_init_helper<T>.
map...
Qt: can't find -lGL error
I just reinstalled QtCreator, created new project ( Qt Application ) an got this after compilation:
8 Answers
...
RE error: illegal byte sequence on Mac OS X
...t a valid UTF-8 char.
Note that, by contrast, GNU sed (Linux, but also installable on macOS) simply passes the invalid byte through, without reporting an error.
Using the formerly accepted answer is an option if you don't mind losing support for your true locale (if you're on a US system and you ne...
Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...