F# Weekly #25 2013

“Design patterns are bug reports against your programming language”

Peter Norvig

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #24

F# Weekly #24 2013

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

Videos/Presentations

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #23

New Twitter API or “F# Weekly” v1.1

Good news for Twitter and no so good for developers:twitter_app

Today(2013-06-11), we(Twitter) are retiring API v1 and fully transitioning to API v1.1.

What does it all mean? This means that all old services are no longer available. Twitter switched to new ones with mandatory OAuth authentication. From now, to work with twitter services we must register new apps and use OAuth.

Also, it means that:

As I know, there are two alternatives available instead of Twitterizer:

  • Tweetsharp (TweetSharp is a fast, clean wrapper around the Twitter API.)
  • LINQ to Twitter (An open source 3rd party LINQ Provider for the Twitter micro-blogging service.)

I have chosen Tweetsharp because its API similar to Twitterizer. This is a new F# Weekly under the hood script:

#r "Newtonsoft.Json.dll"
#r "Hammock.ClientProfile.dll"
#r "TweetSharp.dll"

open TweetSharp
open System
open System.Net
open System.Text.RegularExpressions

let service = new TwitterService(_consumerKey, _consumerSecret)
service.AuthenticateWith(_accessToken, _accessTokenSecret)

let getTweets query =
    let rec collect maxId =
        let options = SearchOptions(Q = query, Count =Nullable(100), MaxId = Nullable(maxId),
                                    Resulttype = Nullable(TwitterSearchResultType.Recent))
        printfn "Loading %s under id %d" query maxId
        let results = service.Search(options).Statuses |> Seq.toList
        printfn "\t Loaded %d tweets" results.Length
        if (results.Length = 0)
            then List.empty
            else
                let lastTweet = results |> List.rev |> List.head
                if (lastTweet.Id < maxId)                     then results |> List.append (collect (lastTweet.Id))
                    else results
    collect (Int64.MaxValue) |> List.rev

let urlRegexp = Regex("http://([\\w+?\\.\\w+])+([a-zA-Z0-9\\~\\!\\@\\#\\$\\%\\^\\&\\*\\(\\)_\\-\\=\\+\\\\\\/\\?\\.\\:\\;\\'\\,]*)?", RegexOptions.IgnoreCase);

let filterUniqLinks (tweets: TwitterStatus list) =
    let hash = new System.Collections.Generic.HashSet();
    tweets |> List.fold
        (fun acc t ->
             let mathces = urlRegexp.Matches(t.Text)
             if (mathces.Count = 0) then acc
             else let urls =
                     [0 .. (mathces.Count-1)]
                     |> List.map (fun i -> mathces.[i].Value)
                     |> List.filter (fun url -> not(hash.Contains(url)))
                  if (List.isEmpty urls) then acc
                  else urls |> List.iter(fun url -> hash.Add(url) |> ignore)
                       t :: acc)
        [] |> List.rev

let tweets =
    ["#fsharp";"#fsharpx";"@dsyme";"#websharper";"@c4fsharp"]
    |> List.map getTweets
    |> List.concat
    |> List.sortBy (fun t -> t.CreatedDate)
    |> filterUniqLinks

let printTweetsInHtml filename (tweets: TwitterStatus list) =
    let formatTweet (text:string) =
        let matches = urlRegexp.Matches(text)
        seq {0 .. (matches.Count-1)}
            |> Seq.fold (
                fun (t:string) i ->
                    let url = matches.[i].Value
                    t.Replace(url, (sprintf "<a href="\&quot;%s\&quot;" target="\&quot;_blank\&quot;">%s</a>" url url)))
                text
    let rows =
      tweets
        |> List.mapi (fun i t ->
            let id = (tweets.Length - i)
            let text = formatTweet(t.Text)
            sprintf "</pre>
<table id="\&quot;%d\&quot;">
<tbody>
<tr>
<td rowspan="\&quot;2\&quot;" width="\&quot;30\&quot;">%d</td>
<td rowspan="\&quot;2\&quot;" width="\&quot;80\&quot;"><a href="\&quot;javascript:remove('%d')\&quot;">Remove</a></td>
<td rowspan="\&quot;2\&quot;"><a href="\&quot;https://twitter.com/%s\&quot;" target="\&quot;_blank\&quot;"><img alt="" src="\&quot;%s\&quot;/" /></a></td>
<td><b>%s</b></td>
</tr>
<tr>
<td>Created : %s</td>
</tr>
</tbody>
</table>
<pre>
"
id id id t.Author.ScreenName t.Author.ProfileImageUrl text (t.CreatedDate.ToString()))
        |> List.fold (fun s r -> s+" "+r) ""
    let html = sprintf "<script type="text/javascript">// <![CDATA[
function remove(id){return (elem=document.getElementById(id)).parentNode.removeChild(elem);}
// ]]></script>%s" rows
 System.IO.File.WriteAllText(filename, html)

printTweetsInHtml "d:\\tweets.html" tweets

F# Weekly #23 2013

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

Videos/Presentations

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #22

F# Weekly #22 2013

Welcome to F# Weekly,

So it’s summer, but F# Weekly is still with you. A roundup of F# content from this past week:

News

Videos/Presentations

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #21

15 Principles for Data Scientists

marksalen's avatarOpen Source Research

I have developed 15 principles for my daily work as a data scientist. These are the principles  that I personally follow :

1- Do not lie with data and do not bullshit: Be honest and frank about empirical evidences. And most importantly do not lie to yourself with data

2- Build everlasting tools and share them with others: Spend a portion of your daily work building tools that makes someone’s life easier. We are freaking humans, we are supposed to be tool builders!

3- Educate yourself continuously: you are a scientist for Bhudda’s sake. Read hardcore math and stats from graduate level textbooks. Never settle down for shitty explanations of a method that you receive from a coworker in the hallway. Learn fundamentals and you can do magic. Read recent papers, go to conferences, publish, and review papers. There is no shortcut for this.

4- Sharpen your skills: learn one language well…

View original post 413 more words

F# Weekly #21 2013

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

Videos/Presentations

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #20

F# Weekly #20 2013

the lhs of an F# developer’s desk

the rhs of an F# developer’s desk

Welcome to F# Weekly,

This past week was full of interesting events and happenings. If you follow F#, you must read all of this carefully. The roundup of F# content:

News

Videos/Presentations

Blogs

That’s all for now.  Have a great week.

Previous F# Weekly edition – #19
lamdbaLadies