Function to show weather forecast in the terminal

[GrouchyGaijin]

Hi Guys,

I found this function that works for the most part.

weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<LOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "%s: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}

See the page:http://www.commandlinefu.com/command...your-location.

My questions are:

1. Does anyone know how I can get rid of the &dein the output: See below

October 5, 2013: Overcast. High 10°C (50°F). Winds 14 kph SSW

2. How I can get the name of the city to show at the top of the forecast like in their example. (See sample output on the link above.)

[Vaphell]

1. s/°/°/g; at the beginning of the perl code
2. in that xml there is no info about the location other than the timezone

[GrouchyGaijin]

Thanks - I figured you would know right off the bat how to sed that stuff out.
I don't follow on #2. I thought the place called /<title> was supposed to show the name of the city if it were /location

[Vaphell]

no, <title> stores date.
relevant parts of the xml look like this:

<title>October 5, 2013</title>
<fcttext>Chance of Rain. High 19&deg;C (66&deg;F). Winds 25 kph SW</fcttext>

the only thing that you can do is to print out the provided parameter or the default value hardcoded in the function, eg

weather()
{
  (( $# )) || set -- "London,UK"
  echo "Location: ${1//,/, }"
  curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=$1" | perl -ne 's/°/°/g;
                                                                                                s/ \(\d+°F\)//g;
                                                                                                /<title>([^<]+)/ && printf "%s: ",$1;
                                                                                                /<fcttext>([^<]+)/ && print $1,"\n"';
}

(oneliners are overrated )
2nd line of the perl block strips Fahrenheits because we don't use them here. If you live in a Fahrenheit country, modify to strip °C with s/\d+°C \((\d+°F)\)/$1/g; but i don't think Sweden is one

$ weather
Location: London, UK
October 5, 2013: Chance of Rain. High 19°C. Winds 25 kph SW
October 6, 2013: Chance of Rain. High 19°C. Winds 10 kph WNW
October 7, 2013: Clear. High 20°C. Winds 10 kph WSW
October 8, 2013: Clear. High 20°C. Winds 10 kph SW
October 9, 2013: Clear. High 19°C. Winds 10 kph West
October 10, 2013: Scattered Clouds. High 19°C. Winds 10 kph NNE
$ weather Washington,DC
Location: Washington, DC
Today: Mostly sunny. Hot with highs in the upper 80s. Northwest winds around 5 mph. 
Tonight: Mostly cloudy. Lows in the upper 60s. Southeast winds around 5 mph. 
Sunday: Partly sunny. Hot with highs in the upper 80s. Southeast winds 5 to 10 mph. 
Sunday Night: Partly cloudy in the evening...then becoming mostly cloudy. Lows in the mid 60s. South winds 5 to 10 mph. 
Monday: Mostly cloudy. Showers...mainly in the afternoon. Highs in the upper 70s. South winds 10 to 15 mph. Chance of rain 80 percent.

[GrouchyGaijin]

Thanks man!

Location: Falun, Sweden
October 5, 2013: Overcast. High 10°C. Winds 14 kph SSW
October 6, 2013: Chance of Rain. High 12°C. Winds 14 kph SSW
October 7, 2013: Overcast. High 13°C. Winds 14 kph SW
October 8, 2013: Partly Cloudy. High 16°C. Winds 14 kph WSW
October 9, 2013: Overcast. High 15°C. Winds 25 kph WSW
October 10, 2013: Scattered Clouds. High 14°C. Winds 21 kph NNW

[GrouchyGaijin]

but i don't think Sweden is one

We use it only if the month has 32 days.

[GrouchyGaijin]

@Vaphell

OK Boss, I need some more guidance

Can you explain why when I run this script:

#!/bin/bash
echo
{  curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=$1" | perl -ne 's/°/°/g;
                                                                                                s/ \(\d+°F\)//g;
                                                                                                /<title>([^<]+)/ && printf "%s: ",$1;
                                                                                                /<fcttext>([^<]+)/ && print $1,"\n"';
}

weather Las Vegas

I'll get a forecast (although in F)

but more often than not particularly if the name of the city has Grand in it. Example: Grand Cayman,Cayman Islands
the script returns nothing. In that case I need to add the %20 between the words.

Is this because of the way the website is coded or something in the command I am issuing?

[Vaphell]

forecast for USian locations seems to be in a different format, it's more verbose. Probably a different data provider so these s/// related to degrees won't work. You'd have to extract the numbers and convert them by hand, but there is another pain - there are no indicators of degrees so you'd have to recognize which numbers are related to temperatures and which to winds.

Either way when you have http://something/something/index.xml?query=something something,something something, the url will obviously end at the first space (as evidenced by the forum software ). In other words space is not a valid url char and has to be replaced with %20. Sure, you can type url with spaces into the webbrowser and it will work but it's a convenience for nublet webusers. Standards are there for a reason
replace $1 with ${1// /%20}.

You need to type the location as a single parameter, eg quoted because $1. weather Las Vegas will return 'Location: Las' because Vegas is $2 and doesn't matter.
If you want your script/function more tolerant you'd have to code around the cases where you can feed multiple params
something like

(( $# )) || set -- "Falun, Sweden"
loc=$*
echo "Location: $loc"
url="http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${loc// /%20}"
  
curl -s "$url" | perl -ne 's/°/°/g;
                           s/ \(\d+°F\)//g;
                           /<title>([^<]+)/ && printf "%s: ",$1;
                           /<fcttext>([^<]+)/ && print $1,"\n";'

difference between $@ and $* is this

$ set -- a b c d e
$ printf "[%s]\n" "$*"
[a b c d e]
$ printf "[%s]\n" "$@"
[a]
[b]
[c]
[d]
[e]

$* glues all parameters into a single string using first char of IFS as a glue (obviously space by default).

$ IFS=:; printf "[%s]\n" "$*"
[a:b:c:d:e]

[ian-weisser]

http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?

That service seems to be deprecated.
Wunderground.com has moved to a purchased-key model for api access. See http://www.wunderground.com/weather/api/

For US locations, I use data from the National Weather Service. No api key required. For how I do it, see http://cheesehead-techblog.blogspot....nfo-feeds.html

The Ubuntu Phone weather app gets worldwide data from OpenWeatherMap.org. It also uses an api key for access, but the price is $0. See http://openweathermap.org/API#forecast

[GrouchyGaijin]

Man, you are a WIZARD