大约有 44,000 项符合查询结果(耗时:0.0249秒) [XML]
Convert pandas dataframe to NumPy array
...early the same (actually, using rec.fromrecords is a bit faster).
df2 = pd.concat([df] * 10000)
%timeit df2.to_records()
%%timeit
v = df2.reset_index()
np.rec.fromrecords(v, names=v.columns.tolist())
11.1 ms ± 557 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
9.67 ms ± 126 µs per l...
How do I read an entire file into a std::string in C++?
...os_type fileSize = ifs.tellg();
ifs.seekg(0, ios::beg);
vector<char> bytes(fileSize);
ifs.read(bytes.data(), fileSize);
return string(bytes.data(), fileSize);
}
This solution resulted in about 20% faster execution times than the other answers presented here, when taking the...
How to convert a byte array to a hex string in Java?
...ly this answer, this is the function I currently use:
private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for (int j = 0; j < bytes.length; j++) {
int v = bytes[j] &...
Convert line-endings for whole directory tree (Git)
...laces line endings and properly handles whitespace, quotes, and shell meta chars.
find . -type f -exec dos2unix {} \;
If you're using dos2unix 6.0 binary files will be ignored.
share
|
improve thi...
Regex match everything after question mark?
... have to use the "dot all" modifier to allow the dot to match the new line character. Whether or not you have to do this, and how to do this, depends on the language you are using. It appears that you forgot to mention the programming language you are using in your question.
Another alternative tha...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...or is expected to for decades. The prime example is compiling X11, macro "Concat3" is broken, it's result is now MISNAMED C Identifier, which of course fails to build. and i'm beginning to thing build fails are their profession.
I think the answer here is "new C that breaks standards is bad C", t...
Can we make unsigned byte in Java
... for the `unsignedByte` variable,
* i.e. `short`, `int`, `long` and even `char`, but during bitwise operations
* it would get casted to `int` anyway.
*/
void printUnsignedByte(byte b) {
int unsignedByte = b & 0xFF;
System.out.println(unsignedByte); // "200"
}
...
No provider for “framework:jasmine”! (Resolving: framework:jasmine)
...ffee": "~0.7.0",
"grunt-contrib-compass": "~0.6.0",
"grunt-contrib-concat": "~0.3.0",
"grunt-contrib-connect": "~0.5.0",
"grunt-contrib-copy": "~0.4.1",
"grunt-contrib-cssmin": "~0.7.0",
"grunt-contrib-htmlmin": "~0.1.3",
"grunt-contrib-imagemin": "~0.3.0",
"grunt-con...
C# equivalent to Java's charAt()?
I know we can use the charAt() method in Java get an individual character in a string by specifying its position. Is there an equivalent method in C#?
...
Print all but the first three columns
.../,"")}1'
4 5 6
If you have an FS that's an RE you can't negate in a character set, you can convert it to a single char first (RS is ideal if it's a single char since an RS CANNOT appear within a field, otherwise consider SUBSEP), then apply the RE interval subsitution, then convert to the OFS...
