I've been memorising digits of pi off and on for years now. Not really sure why other than it is a fun challenge to be able to recite a long string of numbers.

A while back I had found a program that helped me memorise more digits by having a little box to enter the numbers into which would validate each digit as you typed it. The main thing I didn't like about it was that it would erase the entire field of digits if you got one wrong. This was fine up until I got over about 150 digits or so and it just became too painstaking to retype the first hundred or so digits each time to get to the ones I was stuck at.

I decided to use a few days at the end of this summer vacation to put together this web based pi memorisation tool with Javascript. View the source here.

I've added such features as a digit counter to show what place you are at, tips for what the next digits would have been if you make a mistake, and the ability to go back variable amounts when you get one wrong.

I'm totally up for ideas on how to add to this more or make it more useful. I've tested it on multiple browsers but would be very curious to know if its still having bugs with anyone's particular setup.

<brag> And with the added encouragement of making and testing this tool I'm now up over 200 digits. </brag>

Case in point:

def fahrenheit(celsius):
    fahr = (9.0/5.0)*celsius + 32
    return fahr
for temp_c in range (0, 41):
    temp_f = fahrenheit(temp_c)
    print temp_c,"C" , "| %.1f F" % temp_f

Its almost like too-perfect of a language. I feel like I avoid using it because it is just too nice. Its like some sort of super perl that transforms everything into awesomesauce.

For the last couple of days I have been working the chat server and client that I made last semester. Adding additional features to it has been slow but satisfying work.

A weather function has been at the top of my list for things I wanted to see myself implement, so last night I decided to get to working on making something to retrieve the weather.

I've been using the bash script below to get weather information for months now:

#!/bin/bash

var_url="http://www.google.com/ig/api?weather=72959&hl=en"

var_weather_wget=`wget -q $var_url -O -`
var_weather_xml=`echo "$var_weather_wget" | sed 's/<forecast_conditions>.*//'`
var_weather=`echo "$var_weather_xml" | sed 's/></>\n</g'`
var_date=`echo "$var_weather" | grep -e '<forecast_date' | \
sed -e 's/<forecast_date data="//' -e 's/"\/>//'`
var_city=`echo "$var_weather" | grep -e '<city' | \
sed -e 's/<city data="//' -e 's/"\/>//'`
var_condition=`echo "$var_weather" | grep -e '<condition' | \
sed -e 's/<condition data="//' -e 's/"\/>//'`
var_temp_f=`echo "$var_weather" | grep -e '<temp_f' | \
sed -e 's/<temp_f data="//' -e 's/"\/>//'`
var_temp_c=`echo "$var_weather" | grep -e '<temp_c' | \
sed -e 's/<temp_c data="//' -e 's/"\/>//'`
var_humidity=`echo "$var_weather" | grep -e '<humidity' | \
sed -e 's/<humidity data="//' -e 's/"\/>//'`
var_wind=`echo "$var_weather" | grep -e '<wind' | \
sed -e 's/<wind_condition data="//' -e 's/"\/>//'`

echo "Date: $var_date - City: $var_city"
echo "Condition: $var_condition"
echo "Temp: $var_temp_c C"
echo "$var_humidity"
echo "$var_wind"

This has been working well, but I wanted to make something more extensible with Java that I could add to my chatserver and run with any zipcode instead of just having it set to one location.

After finagling around a little I was able to come up with something I'm liking pretty well that fit great into the server I'm putting together:

This has been working well, but I wanted to make something more extensible with Java that I could add to my chatserver and run with any zipcode instead of just having it set to one location.

After finagling around a little I was able to come up with something I'm liking pretty well that fit great into the server I'm putting together:

/*   < <  Current Weather > >      |
    Forecast from Google's API     |
           Spike  Snell            |
               2011                |
----------------------------------*/

import java.io.*;
import java.net.URL;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class weather {

	public static void main(String[] args) throws Exception {

		if (args.length > 0)
			System.out.println(toString(args[0]));
		else
			System.out.println("Please enter a valid 5 digit zipcode. Example: java weather 72701");

	}

	public static BufferedReader read(String url) throws Exception {
		return new BufferedReader(new InputStreamReader(new URL(url).openStream()));
	}

	public static String toString(String zip) throws Exception {
		
		// variables to hold the weather
		String date = null;
		String city = null;
		String condition = null;
		String tempC = null;
		String humidity = null;
		String wind = null;
		
		// declare the pattern and matcher
		Pattern p;
		Matcher m;
		
		// check to make sure the string is the right number of characters
		if (zip.length() != 5) 
			return "Please enter the correct number of digits.";
		
                // and make sure all 5 of the characters are numbers
		p = Pattern.compile("\\d{5}");
		m = p.matcher(zip);
		if (m.find() == false)
			return "Please enter a valid 5 digit zipcode.";

		// open up a connection to google's weather API
		BufferedReader reader = read("http://www.google.com/ig/api?weather="+ zip);
		String page = reader.readLine();

		// get the date
		p = Pattern.compile("<forecast_date data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			date = m.group(1);

		// get the city
		p = Pattern.compile("<city data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			city = m.group(1);

		// get the condition
		p = Pattern.compile("<condition data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			condition = m.group(1);

		// get the temperature in C
		p = Pattern.compile("<temp_c data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			tempC = m.group(1);

		// get the humidity
		p = Pattern.compile("<humidity data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			humidity = m.group(1);

		// get the humidity
		p = Pattern.compile("<wind_condition data=\"(.*?)\"/>");
		m = p.matcher(page);
		if (m.find() == true)
			wind = m.group(1);

		// if the date is still null there was a problem
		if (date == null) {
			return "There was a problem retrieving the weather.";
		}

		else {
			// return the forecast
			return city + " - " + date + 
			       "\nCondition: " + 
			       condition+ "\nTemp: " + 
			       tempC + " *C\n" + 
			       humidity + "\n" + 
			       wind;
		}
	}
}

What it does is taken in a command line argument for the zipcode and after a bit of error checking (Making sure the zipcode is actually 5 numbers) it grabs the data from google's weather API, runs it through some regexes to grab the data I want and then returns everything as a string.

Here is an example of it in use:

nrg@AKIRA ~/Desktop $ java weather 72701
Fayetteville, AR - 2011-07-04
Condition: Mostly Cloudy
Temp: 27 *C
Humidity: 74%
Wind: S at 5 mph

Any feedback on improving this code or any other comments about it would be much appreciated.