easy.Let's take a step at it. The financial industry actually involves the data content is not thousands, cannot statistic, on the contrary, is relatively few. We can count in the bottom of our hearts, such as the type of transaction, account number, account type, password, transaction amount, transaction fee, date and time, merchant code, 2 Magnetic 3 magnetic data, transaction serial number, etc., summed up all can be summed up only about 100 data. Then we can first simple design ISO8583, def
It is found that the negative code is used to calculate and subtract, and the true value of the result is correct. the only problem actually occurs in the special value "0. although we understand that + 0 is the same as-0, 0 is meaningless. in addition, there will be two encoding formats: [0000 0000] original and [1000 0000] original, indicating 0.
The occurrence of the complement solves the problem of the zero symbol and two encodings:
1-1 = 1 + (-1) = [0000 0001] original + [10
This article is a PHP ASCII code conversion class for a detailed analysis of the introduction, the need for friends to refer to the
copy code code as follows:
class ASCII { function decode ($STR) { Preg_match_all ("/(d{2,5})/", $str, $a); $a = $a [0]; foreach ($a as $dec) { if ($dec { $utf. = Chr ($DEC); } else if ($dec { $utf. = Chr (($dec-($dec% 64))/64); $utf. = chr (128 + ($dec% 64)); } Else { $utf. = Chr (224 + ($dec-
After searching for a long time on the Internet, I found various versions. Now I will summarize them to help people check them. By the way, I can give some comments to see which one is the one and which one is the one ····
The first statement:
[R g B]-> [y CB Cr] Conversion-------------------------(R, G, and B are all 8bit unsigned)Y = 0.299 * r + 0.587 * g + 0.114 * B (brightness)CB =-0.1687 * r-0.3313 * g + 0.5 * B + 128Cr = 0.5 * r-0.4187 * g-0.0813 * B +
Yuy2 is often used in TV systems and output formats of many cameras. during processing, we often need to convert it to RGB for processing. Here we will briefly introduce the Conversion Relationship Between yuy2 (YUV) and RGB:
Http://msdn2.microsoft.com/en-us/library/ms893078.aspx
Yuy2 (YUV) to RGB:
C = Y-16
D = u-128
E = V-128
R = clip(( 298 * C + 409 * E + 1
short ) { return value = = (short) obj. Shortvalue (); } return false ; }therefore, regardless of the value of the different types of equality is false; @Test publicvoid testequals () { = 1; = 1; = 1L; System.out.println (Num1.equals (num2)); // false System.out.println (Num2.equals (num3)); // false }
When you assign a value directly, the ValueOf method is called. So be aware of its source code.
differen
When you use HTTPS to access a Web site, ie reminds you that the page must use a more secure Web browser to see that the resource you are accessing uses a 128-bit version of Secure Sockets Layer (SSL) security. To view this resource, you need to use an SSL browser that supports that version. Such as:This problem occurs because the server requires the use of 128 for encryption, the client's browser version i
Numbers in Java appear in the form of a complementThe conversion of byte in Java to a number is also in the form of a complement=================================================The complement of the negative number = the symbol bit of the original code is unchanged the remaining bits are reversed and added a=================================================Special numbers.The complement of two numbers equals itself: one is 0, the other is the maximum negative number in the binary form that can be
to all login users [root @ localhost ~] # Wall Happy New Year Broadcast message from root@localhost.localdomain (pts/0) (Thu Nov 22 05:27:49 2012): Happy New Year [root @ localhost ~] # Login users can receive www.2cto.com [luxh @ localhost ~] $ Broadcast message from root@localhost.localdomain (pts/0) (Thu Nov 22 05:27:49 2012): Happy New Year 3, Command Name: ping run permission: root function description: test network connectivity syntax: ping [option] directly ping the IP address in Linux a
This article provides a detailed analysis of the php ascii code conversion class. For more information, see
The code is as follows:
Class ascii{Function decode ($ str){Preg_match_all ("/(d {2, 5})/", $ str, $ );$ A = $ a [0];Foreach ($ a as $ dec){If ($ dec {$ Utf. = chr ($ dec );}Else if ($ dec {$ Utf. = chr (192 + ($ dec-($ dec % 64)/64 ));$ Utf. = chr (128 + ($ dec % 64 ));}Else{$ Utf. = chr (224 + ($ dec-($ dec % 4096)/4096 ));$ Utf. = chr (
Nodejs Crypto module MD5 and HMAC encryption
In Nodejs, you can use the Crypto module to implement a variety of encryption and decryption processing, in the Crypto module contains similar MD5 or SHA-1 these hashing algorithms, we can implement the HMAC by the Crypto module.
What is an HMAC operation?
The Chinese meaning of the HMAC is: hash operation message authentication code; The operation uses the hashing algorithm to generate a message digest as output with a key and a message as
This article provides a detailed analysis of the php ascii code conversion class. For more information, see
The code is as follows:
Class ascii
{
Function decode ($ str)
{
Preg_match_all ("/(d {2, 5})/", $ str, $ );
$ A = $ a [0];
Foreach ($ a as $ dec)
{
If ($ dec {
$ Utf. = chr ($ dec );
}
Else if ($ dec {
$ Utf. = chr (192 + ($ dec-($ dec % 64)/64 ));
$ Utf. = chr (128 + ($ dec % 64 ));
}
Else
{
$ Utf. = chr (224 + ($ dec-($ dec % 4096)/4096 ));
$
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.