大约有 13,800 项符合查询结果（耗时：0.0427秒） [XML]
Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...
Upgrading PHP in XAMPP for Windows?
...e\bin with the newer versions.
Now the trick: take the files which have a '_2' in their names (for example php5apache2_2.dll or php5apache2_2_filter.dll), copy them in the apache\bin subdirectory and remove the '_2' part, overwriting the existing files. This is necessary because by XAMPP uses Apache...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...use a query like this: "start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * ...
Naming returned columns in Pandas aggregate function? [duplicate]
...l() function on the multi-level column to form new labels:
df.columns = ["_".join(x) for x in df.columns.ravel()]
For example:
import pandas as pd
import pandas.rpy.common as com
import numpy as np
data = com.load_data('Loblolly')
print(data.head())
# height age Seed
# 1 4.51 3 3...
Extracting text OpenCV
...s(cv::Mat img)
{
std::vector<cv::Rect> boundRect;
cv::Mat img_gray, img_sobel, img_threshold, element;
cvtColor(img, img_gray, CV_BGR2GRAY);
cv::Sobel(img_gray, img_sobel, CV_8U, 1, 0, 3, 1, 0, cv::BORDER_DEFAULT);
cv::threshold(img_sobel, img_threshold, 0, 255, CV_THRESH_O...
Handling an empty UITableView. Print a friendly message
...xtension:
import UIKit
extension UITableView {
func setEmptyMessage(_ message: String) {
let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.bounds.size.width, height: self.bounds.size.height))
messageLabel.text = message
messageLabel.textColor = .black
...
Installing PDO driver on MySQL Linux server
...-get install php5-mysql
There is no limitation between using PDO and mysql_ simultaneously. You will however need to create two connections to your DB, one with mysql_ and one using PDO.
share
|
im...
Where can I learn how to write C code to speed up slow R functions? [closed]
...:
SEXP foobar(){
SEXP ab;
PROTECT(ab = allocVector(STRSXP, 2));
SET_STRING_ELT( ab, 0, mkChar("foo") );
SET_STRING_ELT( ab, 1, mkChar("bar") );
UNPROTECT(1);
}
Using Rcpp, you can write the same function as:
SEXP foobar(){
return Rcpp::CharacterVector::create( "foo", "bar" ) ;
}
...
What is the difference between C# and .NET?
...ment 0x00000200
.stackreserve 0x00100000
.subsystem 0x0003 // WINDOWS_CUI
.corflags 0x00000001 // ILONLY
// Image base: 0x05DB0000
// =============== CLASS MEMBERS DECLARATION ===================
.class public auto ansi beforefieldinit Example.Class1
extends [mscorlib]System.Objec...
Thread Safety in Python's dictionary
...mic operations, there are corner cases where they aren’t atomic (e.g. if __hash__ or __eq__ are implemented as Python methods) and their atomicity should not be relied upon. Neither should you rely on atomic variable assignment (since this in turn depends on dictionaries).
Use the Queue module's Q...