Locust Proxy

Parsing math expressions correctly involves converting mathematical expressions from their human-readable form into a format that a computer can understand and evaluate. A common approach is to use a parser or library designed for mathematical expressions.

In Python, you can use the sympy library, which provides powerful symbolic mathematics capabilities, including expression parsing and evaluation. Here's an example:

from sympy import sympify, symbols

# Define symbols
x, y = symbols('x y')

# Parse math expressions
expression1 = sympify("2*x + 3*y")
expression2 = sympify("sin(x) + cos(x)")

# Evaluate expressions
result1 = expression1.subs({x: 1, y: 2})
result2 = expression2.subs(x, 0)

print("Result 1:", result1)
print("Result 2:", result2)

In this example, sympify is used to parse the mathematical expressions. You can then substitute values for variables using the subs method.

If you need a more general-purpose parser, you can use the pyparsing library. Here's a basic example:

from pyparsing import Word, nums, operatorPrecedence, opAssoc

# Define grammar for basic math expressions
integer = Word(nums).setParseAction(lambda t: int(t[0]))
variable = Word("xy")
operand = integer | variable
expr = operatorPrecedence(
    operand,
    [
        ("+", 2, opAssoc.LEFT),
        ("-", 2, opAssoc.LEFT),
        ("*", 3, opAssoc.LEFT),
        ("/", 3, opAssoc.LEFT),
    ],
)

# Parse math expressions
expression1 = expr.parseString("2*x + 3*y")
expression2 = expr.parseString("sin(x) + cos(x)")

print("Parsed Expression 1:", expression1)
print("Parsed Expression 2:", expression2)

This example uses pyparsing to define a grammar for basic math expressions with addition, subtraction, multiplication, and division. You can customize the grammar based on your specific needs.

Choose the library that best fits your requirements, whether it's for symbolic mathematics (like sympy) or general-purpose expression parsing (like pyparsing). Always consider error handling and validation when working with user-inputted expressions.

In Android, you can load and parse XML using the XmlPullParser class provided by Android's org.xmlpull.v1 package. The following example demonstrates how to load and parse XML from a string resource in Android

Assuming you have an XML file (example.xml) in the res/xml directory with the following content:

    Item 1
    Item 2
    Item 3

Now, you can load and parse this XML file in an Android activity:

import android.app.Activity;
import android.content.res.XmlResourceParser;
import android.os.Bundle;
import android.util.Log;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;

import java.io.IOException;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Load and parse XML
        parseXml();
    }

    private void parseXml() {
        try {
            // Get the XML resource parser
            XmlResourceParser parser = getResources().getXml(R.xml.example);

            int eventType = parser.getEventType();
            while (eventType != XmlPullParser.END_DOCUMENT) {
                if (eventType == XmlPullParser.START_TAG) {
                    // Check the name of the start tag
                    if ("item".equals(parser.getName())) {
                        // Get attributes
                        String id = parser.getAttributeValue(null, "id");
                        String text = parser.nextText();

                        // Process the data (in this example, print it)
                        Log.d("XML Parsing", "ID: " + id + ", Text: " + text);
                    }
                }

                eventType = parser.next();
            }
        } catch (XmlPullParserException | IOException e) {
            e.printStackTrace();
        }
    }
}

In this example:

• getResources().getXml(R.xml.example) is used to obtain an XmlResourceParser for the XML file (example.xml).
• The XmlPullParser is used to iterate through the XML content, and when a start tag is encountered (XmlPullParser.START_TAG), it checks for the tag name ("item" in this case) and retrieves attributes and text content accordingly.

Remember to replace R.xml.example with the actual resource ID for your XML file. This example assumes that the XML file is located in the res/xml directory.

Also, ensure that the XML file is well-formed and follows the XML structure.

The term "public" should be understood to mean open proxy servers. That is, they can be used by all users without exception. They can be insecure and are often quite overloaded, so the connection speed or response time when using public proxies can be very slow.

Google Chrome doesn't have a built-in function to work with a proxy server, although there is such an item in the settings. But when you click on it, you are automatically "redirected" to the standard proxy settings in Windows (or any other operating system).

It is recommended to use third-party programs that allow redirecting all traffic through a proxy server. For example, ProxyDroid, EveryProxy. It is not possible to use proxies through the regular menu. Although in phones from some manufacturers such possibility has been added.