asubb’s gists

asubb / compressHash.kt

Last active January 22, 2020 15:35

Hash values are in fact very long number written as hex number. For using it as string it is sometimes waste of space (i.e. as identifier or something). That function kinda compresses the string by using more digits for this number. How many digits? It's up to you.

	import kotlin.math.max
	import kotlin.random.Random

	fun compressHash(hexV: String, digits: String = "0123456789abcdefghijklmnopqrstuvwxyz"): String {

	val hexDigits = "0123456789abcdef"
	val zero = hexDigits.first()

	fun dropLeadingZeros(hexV: String): String {
	var v = hexV

asubb / wave-blog:using-jupyter.Dockerfile

Last active May 20, 2020 03:16

wave-blog/using-jupyter/dockerfile

	FROM jupyter/base-notebook

	USER root

	# Install OpenJDK-8
	RUN apt-get update && \
	apt-get install -y openjdk-8-jdk && \
	apt-get install -y ant && \
	apt-get clean;

asubb / wave-blog:using-jupyter:imports.kt

Created April 10, 2020 20:31

wave-blog/using-jupyter/imports.kt

	%use lets-plot

	@file:Repository("https://dl.bintray.com/wavebeans/wavebeans")
	@file:DependsOn("io.wavebeans:lib:0.0.3")

	import io.wavebeans.lib.*
	import io.wavebeans.lib.io.*
	import io.wavebeans.lib.math.*
	import io.wavebeans.lib.stream.*
	import io.wavebeans.lib.stream.fft.*

asubb / wave-blog:using-jupyter:short.signal.kt

Created April 10, 2020 21:01

wave-blog/using-jupyter/short.signal.kt

	val o = (880.sine() + 440.sine() + 220.sine())
	.trim(1000, MILLISECONDS)

	val values = o.asSequence(44100.0f)
	.drop(500)
	.take(400)
	.map { it.asDouble() }
	.toList()

	val values2 = o.asSequence(44100.0f)

asubb / wave-blog:using-jupiter:long.imports.kt

Created April 10, 2020 21:12

wave-blog/using-jupiter/long.imports.kt

	%use lets-plot

	@file:Repository("https://dl.bintray.com/wavebeans/wavebeans")
	@file:DependsOn("io.wavebeans:lib:0.0.3")
	@file:DependsOn("io.wavebeans:exe:0.0.3")
	@file:DependsOn("io.wavebeans:http:0.0.3")

	import io.wavebeans.lib.*
	import io.wavebeans.lib.io.*
	import io.wavebeans.lib.math.*

asubb / wave-blog:using-jupyter:long.signal.kt

Created April 10, 2020 21:17

wave-blog/using-jupyter/long.signal.kt

	//Specify the parameters of future calculations:
	val windowSize = 801
	val stepSize = 256
	val fftSize = 1024

	// Define a signal, windowed sum of sinusoids:
	val signal = (880.sine() + 440.sine() + 220.sine())
	.window(windowSize, stepSize)

	// The first FFT applying the triangular window function:

asubb / wave-blog:using-jupyter:long.signal.exe.kt

Created April 10, 2020 21:19

wave-blog/using-jupyter/long.signal.exe.kt

	val overseer = LocalDistributedOverseer(
	listOf(triangularFft, hammingFft),
	threadsCount = 2,
	partitionsCount = 2
	)

	val errors = overseer.eval(44100.0f)
	.map { it.get().exception }
	.filterNotNull()
	.toList()

asubb / wave-blog:using-jupyter:long.signal.query.imports.kt

Created April 10, 2020 21:21

wave-blog/using-jupyter/long.signal.query.imports.kt

	%use klaxon
	%use lets-plot

	import java.net.*
	import jetbrains.letsPlot.scale.*

asubb / wave-blog:using-jupyter:long.signal.query.types.kt

Created April 10, 2020 21:23

wave-blog/using-jupyter/long.signal.query.types.kt

	data class FftSample(
	val index: Long,
	val binCount: Int,
	val samplesCount: Int,
	val sampleRate: Float,
	val magnitude: List<Double>,
	val phase: List<Double>,
	val frequency: List<Double>,
	val time: Long
	)

asubb / wave-blog:using-jupyter:long.signal.query.func.kt

Created April 10, 2020 21:27

wave-blog/using-jupyter/long.signal.query.func.kt

	fun fftData(table: String, freqCutOff: Pair<Int, Int>): Map<String, List<Any>> {
	val k = Klaxon()
	val server = "http://localhost:6800"

	// 1. read and deserializae the data
	val data = URL("$server/table/$table/last?interval=10s").openStream().reader().readLines()
	.map { k.parse<Result>(it)!! }

	// 2. Calculate the time value to shift values to 0 by x-axis
	val timeShift = data.asSequence().map { it.value.time }.min() ?: 0