Juliaでワードクラウドを作る WordCloud.jl

JuliaのパッケージWordCloud.jlを使用してワードクラウドを作ってみます。パッケージのgithubは↓

https://github.com/guo-yong-zhi/WordCloud.jl

Julia Discourseは↓

https://discourse.julialang.org/t/ann-wordcloud-jl-a-word-cloud-generator-in-julia/53587

基本のチュートリアル

githubのReadmeのまま以下のように実行してみますと、簡単にワードクラウドが出力されました。

using WordCloud
using Random
words = [randstring(rand(1:8)) for i in 1:300]
weights = randexp(length(words))
wc1 = wordcloud(words, weights)
generate!(wc1)
paint(wc1, "random.svg")

次にもうひとつのチュートリアルaliceを実行してみます。

## ImageIO とImageMagickが必要
## メモ:'stopwords'は除外語のリスト
using WordCloud
stopwords = WordCloud.stopwords_en ∪ ["said"]
textfile = pkgdir(WordCloud)*"/res/alice.txt"
maskfile = pkgdir(WordCloud)*"/res/alice_mask.png"
wc = wordcloud(
    processtext(open(textfile), stopwords=stopwords, maxnum=500), 
    mask = maskfile,
    maskcolor="#faeef8",
    outline = 4,
    linecolor = "purple",
    colors = :Set1_5,
    angles = (0, 90),
    fonts = "Tahoma",
    density = 0.5) |> generate!
paint(wc, "alice.png", ratio=0.5)

結果として不思議の国のアリスの形にマスクされたワードクラウドが出来上がりました。

比較的短いコードでワードクラウドが作れますね。ちなみに先程の不思議の国のアリスのワードクラウドで参照していたalice.txtは以下のようなテキストファイルでした（本物は長いため一部のみ表示）。おそらく不思議の国のアリスの全文だと思います

Project Gutenberg's Alice's Adventures in Wonderland, by Lewis Carroll

This eBook is for the use of anyone anywhere at no cost and with
almost no restrictions whatsoever.  You may copy it, give it away or
re-use it under the terms of the Project Gutenberg License included
with this eBook or online at www.gutenberg.org


Title: Alice's Adventures in Wonderland

Author: Lewis Carroll

Posting Date: June 25, 2008 [EBook #11]
Release Date: March, 1994
[Last updated: December 20, 2011]

Language: English


*** START OF THIS PROJECT GUTENBERG EBOOK ALICE'S ADVENTURES IN WONDERLAND ***


ALICE'S ADVENTURES IN WONDERLAND

Lewis Carroll

THE MILLENNIUM FULCRUM EDITION 3.0

CHAPTER I. Down the Rabbit-Hole

Alice was beginning to get very tired of sitting by her sister on the
bank, and of having nothing to do: once or twice she had peeped into the
book her sister was reading, but it had no pictures or conversations in
it, 'and what is the use of a book,' thought Alice 'without pictures or
conversation?'

So she was considering in her own mind (as well as she could, for the
hot day made her feel very sleepy and stupid), whether the pleasure
of making a daisy-chain would be worth the trouble of getting up and
picking the daisies, when suddenly a White Rabbit with pink eyes ran
close by her.

There was nothing so VERY remarkable in that; nor did Alice think it so
VERY much out of the way to hear the Rabbit say to itself, 'Oh dear!
Oh dear! I shall be late!' (when she thought it over afterwards, it
occurred to her that she ought to have wondered at this, but at the time
it all seemed quite natural); but when the Rabbit actually TOOK A WATCH
OUT OF ITS WAISTCOAT-POCKET, and looked at it, and then hurried on,
Alice started to her feet, for it flashed across her mind that she had
never before seen a rabbit with either a waistcoat-pocket, or a watch
to take out of it, and burning with curiosity, she ran across the field
after it, and fortunately was just in time to see it pop down a large
rabbit-hole under the hedge.

In another moment down went Alice after it, never once considering how
in the world she was to get out again.

The rabbit-hole went straight on like a tunnel for some way, and then
dipped suddenly down, so suddenly that Alice had not a moment to think
about stopping herself before she found herself falling down a very deep
well.

Either the well was very deep, or she fell very slowly, for she had
plenty of time as she went down to look about her and to wonder what was
going to happen next. First, she tried to look down and make out what
she was coming to, but it was too dark to see anything; then she
looked at the sides of the well, and noticed that they were filled with
cupboards and book-shelves; here and there she saw maps and pictures
hung upon pegs. She took down a jar from one of the shelves as
she passed; it was labelled 'ORANGE MARMALADE', but to her great
disappointment it was empty: she did not like to drop the jar for fear
of killing somebody, so managed to put it into one of the cupboards as
she fell past it.

弄ってみる　『I have a dream』のワードクラウド

今回、練習でキング牧師の名演説『I have a dream』をワードクラウド化してみます。原文は以下から拝借しました。

https://www.americanrhetoric.com/speeches/mlkihaveadream.htm

テキストファイルの作成

カレントディレクトリに演説原文をコピーしたIhaveaDream.txtを作成します。

以下のような感じです（冒頭のみ紹介）

I am happy to join with you today in what will go down in history as the greatest demonstration for freedom in the history of our nation.

Five score years ago, a great American, in whose symbolic shadow we stand today, signed the Emancipation Proclamation. This momentous decree came as a great beacon light of hope to millions of Negro slaves who had been seared in the flames of withering injustice. It came as a joyous daybreak to end the long night of their captivity.

But one hundred years later, the Negro still is not free. One hundred years later, the life of the Negro is still sadly crippled by the manacles of segregation and the chains of discrimination. One hundred years later, the Negro lives on a lonely island of poverty in the midst of a vast ocean of material prosperity. One hundred years later, the Negro is still languished in the corners of American society and finds himself an exile in his own land. And so we've come here today to dramatize a shameful condition.

In a sense we've come to our nation's capital to cash a check. When the architects of our republic wrote the magnificent words of the Constitution and the Declaration of Independence, they were signing a promissory note to which every American was to fall heir. This note was a promise that all men, yes, black men as well as white men, would be guaranteed the "unalienable Rights" of "Life, Liberty and the pursuit of Happiness." It is obvious today that America has defaulted on this promissory note, insofar as her citizens of color are concerned. Instead of honoring this sacred obligation, America has given the Negro people a bad check, a check which has come back marked "insufficient funds."

But we refuse to believe that the bank of justice is bankrupt. We refuse to believe that there are insufficient funds in the great vaults of opportunity of this nation. And so, we've come to cash this check, a check that will give us upon demand the riches of freedom and the security of justice.

We have also come to this hallowed spot to remind America of the fierce urgency of Now. This is no time to engage in the luxury of cooling off or to take the tranquilizing drug of gradualism. Now is the time to make real the promises of democracy. Now is the time to rise from the dark and desolate valley of segregation to the sunlit path of racial justice. Now is the time to lift our nation from the quicksands of racial injustice to the solid rock of brotherhood. Now is the time to make justice a reality for all of God's children.

It would be fatal for the nation to overlook the urgency of the moment. This sweltering summer of the Negro's legitimate discontent will not pass until there is an invigorating autumn of freedom and equality. Nineteen sixty-three is not an end, but a beginning. And those who hope that the Negro needed to blow off steam and will now be content will have a rude awakening if the nation returns to business as usual. And there will be neither rest nor tranquility in America until the Negro is granted his citizenship rights. The whirlwinds of revolt will continue to shake the foundations of our nation until the bright day of justice emerges.

But there is something that I must say to my people, who stand on the warm threshold which leads into the palace of justice: In the process of gaining our rightful place, we must not be guilty of wrongful deeds. Let us not seek to satisfy our thirst for freedom by drinking from the cup of bitterness and hatred. We must forever conduct our struggle on the high plane of dignity and discipline. We must not allow our creative protest to degenerate into physical violence. Again and again, we must rise to the majestic heights of meeting physical force with soul force.

The marvelous new militancy which has engulfed the Negro community must not lead us to a distrust of all white people, for many of our white brothers, as evidenced by their presence here today, have come to realize that their destiny is tied up with our destiny. And they have come to realize that their freedom is inextricably bound to our freedom.

We cannot walk alone.

And as we walk, we must make the pledge that we shall always march ahead.

We cannot turn back.

プログラムの作成

下記のようにプログラムを作成してみます。すると、問題なくワードクラウドが作成されました。

using WordCloud
textfile = "IhaveaDream.txt"
wc3 = wordcloud(
    processtext(open(textfile), maxnum=500), 
    outline = 4,
    linecolor = "purple",
    colors = :Set1_5,
    angles = (0, 90),
    fonts = "Tahoma",
    density = 0.5) |> generate!
paint(wc3, "IhaveDream.png", ratio=0.5)

マスクの作成と適用

続いて、マスクを作成してみます。カレントディレクトリにペイントで適当に絵を描いて、mask.pngで保存します。 ↓のように描いてみました。

その後、下記のようにプログラムを作成し実行すると以下のようにうまくマスクすることができました。

using WordCloud
textfile = "IhaveaDream.txt"
maskfile = "mask.png"
wc3 = wordcloud(
    processtext(open(textfile), maxnum=500), 
    mask = maskfile,
    maskcolor="#faeef8",
    outline = 4,
    linecolor = "purple",
    colors = :Set1_5,
    angles = (0, 90),
    fonts = "Tahoma",
    density = 0.5) |> generate!
paint(wc3, "IhaveDream2.png", ratio=0.5)