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Pandas read_csv low_memory and dtype options
...ain use is for indexing. See more here
'Int8', 'Int16', 'Int32', 'Int64', 'UInt8', 'UInt16', 'UInt32', 'UInt64' are all pandas specific integers that are nullable, unlike the numpy variant.
'string' is a specific dtype for working with string data and gives access to the .str attribute on the series...
Creating a BLOB from a Base64 string in JavaScript
...his array of byte values into a real typed byte array by passing it to the Uint8Array constructor.
const byteArray = new Uint8Array(byteNumbers);
This in turn can be converted to a BLOB by wrapping it in an array and passing it to the Blob constructor.
const blob = new Blob([byteArray], {type: c...
MFC CListCtrl使用方法详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...info.pt = point;
lvinfo.flags = LVHT_ABOVE;
UINT nFlag;
int nItem = m_list.HitTest(point, &nFlag);
//判断是否点在checkbox上
if(nFlag == LVHT_ONITEMSTATEICON)
{
AfxMessageBox("点在listctrl的check...
How can I programmatically generate keypress events in C#?
..."user32.dll")]
public static extern void keybd_event(byte bVk, byte bScan, uint dwFlags, uint dwExtraInfo);
sample code is given below:
const int VK_UP = 0x26; //up key
const int VK_DOWN = 0x28; //down key
const int VK_LEFT = 0x25;
const int VK_RIGHT = 0x27;
const uint KEYEVENTF_KEYUP = 0x0002;
...
How to check file MIME type with javascript before upload?
... = new FileReader();
fileReader.onloadend = function(e) {
var arr = (new Uint8Array(e.target.result)).subarray(0, 4);
var header = "";
for(var i = 0; i < arr.length; i++) {
header += arr[i].toString(16);
}
console.log(header);
// Check the file signature against known types
};
...
Most common C# bitwise operations on enums
...umerable.Range(0, 64)
.Where(bit => ((flags.GetTypeCode() == TypeCode.UInt64 ? (long)(ulong)flags : Convert.ToInt64(flags)) & (1L << bit)) != 0)
.Select(bit => Enum.ToObject(flags.GetType(), 1L << bit))`
Enums.NET flags.GetFlags()
I'm trying to get these improvements i...
What encoding/code page is cmd.exe using?
...<stdio.h>
#include <windows.h>
int main() {
int c, n;
UINT oldCodePage;
char buf[1024];
oldCodePage = GetConsoleOutputCP();
if (!SetConsoleOutputCP(65001)) {
printf("error\n");
}
freopen("uc-test-UTF-8-nobom.txt", "rb", stdin);
n = fread(buf, si...
What is the difference between a weak reference and an unowned reference?
...(name: String) { self.name = name }
}
class CreditCard {
let number: UInt64
unowned let customer: Customer
init(number: UInt64, customer: Customer) { self.number = number; self.customer = customer }
}
In this example, a Customer may or may not have a CreditCard, but a CreditCard will ...
How do I shutdown, restart, or log off Windows via a bat file?
...ctual function signature for ExitWindowsEx is:
BOOL WINAPI ExitWindowsEx(UINT uFlags, DWORD dwReserved);
in 2011: "Throwing garbage on the sidewalk: The sad history of the rundll32 program"
And to make it crystal-clear:
in 2013 "What's the guidance on when to use rundll32? Easy: Don't use i...
reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?
...llowing
data types are atomic: bool, char,
byte, sbyte, short, ushort, uint, int,
float, and reference types."
So, you can write to the volatile reference without risk of getting a corrupted value.
You should of course be careful with how you decide which thread should fetch the new data, t...