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End Sub</lang>
=={{header|Vlang}}==
{{trans|Go}}
<br>
As Vlang doesn't have any audio support in its standard library, we instead build a .wav file which can then be played using a utility such as SoX.
<lang vlang>import strings
import os
import encoding.binary
import math
const (
sample_rate = 44100
duration = 8
data_length = sample_rate * duration
hdr_size = 44
file_len = data_length + hdr_size - 8
)
fn main() {
// buffers
mut buf1 := []byte{len:1}
mut buf2 := []byte{len:2}
mut buf4 := []byte{len:4}
// WAV header
mut sb := strings.new_builder(128)
sb.write_string("RIFF")
binary.little_endian_put_u32(mut &buf4, file_len)
sb.write(buf4)? // file size - 8
sb.write_string("WAVE")
sb.write_string("fmt ")
binary.little_endian_put_u32(mut &buf4, 16)
sb.write(buf4)? // length of format data (= 16)
binary.little_endian_put_u16(mut &buf2, 1)
sb.write(buf2)? // type of format (= 1 (PCM))
sb.write(buf2)? // number of channels (= 1)
binary.little_endian_put_u32(mut &buf4, sample_rate)
sb.write(buf4)? // sample rate
sb.write(buf4)? // sample rate * bps(8) * channels(1) / 8 (= sample rate)
sb.write(buf2)? // bps(8) * channels(1) / 8 (= 1)
binary.little_endian_put_u16(mut &buf2, 8)
sb.write(buf2)? // bits per sample (bps) (= 8)
sb.write_string("data")
binary.little_endian_put_u32(mut &buf4, data_length)
sb.write(buf4)? // size of data section
wavhdr := sb.str().bytes()
// write WAV header
mut f := os.create("notes.wav")?
defer {
f.close()
}
f.write(wavhdr)?
// compute and write actual data
freqs := [261.6, 293.6, 329.6, 349.2, 392.0, 440.0, 493.9, 523.3]!
for j in 0..duration {
freq := freqs[j]
omega := 2 * math.pi * freq
for i in 0..data_length/duration {
y := 32 * math.sin(omega*f64(i)/f64(sample_rate))
buf1[0] = u8(math.round(y))
f.write(buf1)?
}
}
}</lang>
=={{header|Wren}}==
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