Data update

Task/Morse-code/Pluto/morse-code.pluto

@@ -0,0 +1,60 @@
+local audio = require "audio"
+
+local char_to_morse = {
+    ["!"] = "---.",   ['"'] = ".-..-.",  ["$"] = "...-..-", ["'"] = ".----.",
+    ["("] = "-.--.",  [")"] = "-.--.-",  ["+"] = ".-.-.",   [","] = "--..--",
+    ["-"] = "-....-", ["."] = ".-.-.-",  ["/"] = "-..-.",
+    ["0"] = "-----",  ["1"] = ".----",   ["2"] = "..---",   ["3"] = "...--",
+    ["4"] = "....-",  ["5"] = ".....",   ["6"] = "-....",   ["7"] = "--...",
+    ["8"] = "---..",  ["9"] = "----.",
+    [":"] = "---...", [";"] = "-.-.-.",  ["="] = "-...-",   ["?"] = "..--..",
+    ["@"] = ".--.-.",
+    ["A"] = ".-",     ["B"] = "-...",    ["C"] = "-.-.",    ["D"] = "-..",
+    ["E"] = ".",      ["F"] = "..-.",    ["G"] = "--.",     ["H"] = "....",
+    ["I"] = "..",     ["J"] = ".---",    ["K"] = "-.-",     ["L"] = ".-..",
+    ["M"] = "--",     ["N"] = "-.",      ["O"] = "---",     ["P"] = ".--.",
+    ["Q"] = "--.-",   ["R"] = ".-.",     ["S"] = "...",     ["T"] = "-",
+    ["U"] = "..-",    ["V"] = "...-",    ["W"] = ".--",     ["X"] = "-..-",
+    ["Y"] = "-.--",   ["Z"] = "--..",
+    ["["] = "-.--.",  ["]"] = "-.--.-",  ["_"] = "..--.-"
+}
+
+local function text_to_morse(text)
+    text = text:upper()
+    local morse = ""
+    for i = 1, #text do
+        local c = text[i]
+        if c == " " then
+            morse ..= string.rep(" ", 7)
+        else
+            local m = char_to_morse[c]
+            if m then morse ..= m:split(""):concat(" ") .. "   " end
+        end
+    end
+    return morse:rstrip()
+end
+
+local morse = text_to_morse("Hello world!")
+print(morse) -- print to terminal
+
+-- Now create a .wav file.
+morse = morse:replace("-", "...")  -- replace 'dash' with 3 'dot's
+local data = {}
+local sample_rate = 44100
+local samples = 0.2 * sample_rate  -- number of samples assuming 'dot' takes 200 ms
+local freq = 500  -- say
+local omega = 2 * math.pi * freq
+for i = 1, #morse do
+    local c = morse[i]
+    if c == "." then
+        for s = 0, samples -1 do
+            local value = math.round(32 * math.sin(omega * s / sample_rate)) & 255
+            data:insert(value)
+        end
+    else
+        for _ = 1, samples do data:insert(0) end
+    end
+end
+local filepath = "morse_code.wav"
+audio.create(filepath, data, sample_rate)
+audio.play(filepath)