commit 20caf7be23b8f2e4d51ce152e8f29325636ea645
parent 97d8e0662db1db25083e94196732cbefa6c24a7f
Author: Matt Demanett <matt@demanett.net>
Date: Mon, 13 Jan 2020 01:04:36 -0500
Better plotting; scater plotting.
Diffstat:
6 files changed, 175 insertions(+), 3 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -38,4 +38,7 @@ testmain
releasenote.md
plot
plot.*
+scatter
+scatter.*
lldb.cmd
+!test/*
diff --git a/Makefile b/Makefile
@@ -43,8 +43,22 @@ plot: $(PLOT_OBJECTS)
plotrun: plot
./plot
plotrungp: plot
- ./plot > plot.tmp && gnuplot -e "set yrange [0:1.1]; plot 'plot.tmp' using 1:2 with lines"
+ # ./plot > plot.tmp && gnuplot -p -e "set yrange [0:1.1]; plot 'plot.tmp' using 1:2 with lines"
+ ./plot > plot.tmp && gnuplot -p test/plot.gp
plot_clean:
- rm -f plot $(PLOT_OBJECTS)
+ rm -f plot plot.tmp $(PLOT_OBJECTS)
-clean: benchmark_clean testmain_clean plot_clean
+SCATTER_SOURCES = $(wildcard test/scatter.cpp src/dsp/*cpp)
+SCATTER_OBJECTS = $(patsubst %, build/%.o, $(SCATTER_SOURCES))
+SCATTER_DEPS = $(patsubst %, build/%.d, $(SCATTER_SOURCES))
+-include $(SCATTER_DEPS)
+scatter: $(SCATTER_OBJECTS)
+ $(CXX) -o $@ $^
+scatterrun: scatter
+ ./scatter
+scatterrungp: scatter
+ ./scatter > scatter.tmp && gnuplot -p test/scatter.gp
+scatter_clean:
+ rm -f scatter scatter.tmp $(SCATTER_OBJECTS)
+
+clean: benchmark_clean testmain_clean plot_clean scatter_clean
diff --git a/test/plot.cpp b/test/plot.cpp
@@ -0,0 +1,48 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <math.h>
+#include <algorithm>
+
+#include "dsp/analyzer.hpp"
+#include "dsp/signal.hpp"
+
+using namespace bogaudio::dsp;
+
+// KaiserWindow w(1024);
+// float y(float x) {
+// return w._window[(int)x];
+// }
+
+// Chebyshev gain coefficient; x is ripple.
+// float y(float x) {
+// float e = x / 10.0;
+// e = std::pow(10.0f, e);
+// e -= 1.0f;
+// e = std::sqrt(e);
+//
+// return 1.0f / (2.0f * e);
+// }
+
+// Q https://en.wikipedia.org/wiki/Q_factor
+float y(float x) {
+ x *= 2.0f;
+ return std::pow(2.0f, x / 2.0f) / (std::pow(2.0f, x) - 1.0f);
+}
+
+int main() {
+ const float xMin = 0.1f;
+ // const float xMax = 1023.0f;
+ const float xMax = 3.0f;
+ const float samples = 1024.0f;
+
+ const float delta = (xMax - xMin) / samples;
+ float x = xMin;
+ while (x <= xMax) {
+ printf("%f, %f\n", x, y(x));
+ x += delta;
+ }
+ // printf("%f\n", y(1.0f));
+ return 0;
+}
diff --git a/test/plot.gp b/test/plot.gp
@@ -0,0 +1,7 @@
+set zeroaxis
+# r = 2
+# set xrange[-r:r]
+# set yrange[-r:r]
+set grid
+
+plot 'plot.tmp' using 1:2 with lines
diff --git a/test/scatter.cpp b/test/scatter.cpp
@@ -0,0 +1,93 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <math.h>
+#include <cmath>
+#include <algorithm>
+
+struct Scatter {
+ virtual ~Scatter() {}
+ virtual bool next(float& x, float &y) = 0;
+};
+
+struct TestScatter : Scatter {
+ int i = 0;
+
+ bool next(float& x, float &y) override {
+ x = i;
+ y = i;
+ ++i;
+ return i < 5;
+ }
+};
+
+struct ButterworthPoles : Scatter {
+ int k = 1;
+ int n;
+ bool conjugate = false;
+
+ ButterworthPoles(int n) : n(n) {}
+
+ bool next(float& x, float &y) override {
+ float a = ((float)(2 * k + n - 1)) * M_PI / (float)(2 * n);
+
+ x = std::cos(a);
+ y = std::sin(a);
+ if (conjugate) {
+ y = -y;
+ }
+ conjugate = !conjugate;
+ k += !conjugate;
+ return k <= n / 2;
+ }
+};
+
+struct ChebyshevPoles : Scatter {
+ int k = 1;
+ int n;
+ double ripple;
+ double e;
+ double ef;
+ bool conjugate = false;
+
+ ChebyshevPoles(int n, double ripple) : n(n), ripple(ripple) {
+ e = ripple / 10.0;
+ e = std::pow(10.0, e);
+ e -= 1.0f;
+ e = std::sqrt(e);
+
+ ef = std::asinh(1.0 / e) / (float)n;
+ }
+
+ bool next(float& x, float &y) override {
+ double a = ((double)(2 * k + n - 1)) * M_PI / (double)(2 * n);
+
+ x = -std::sinh(ef) * std::sin(a);
+ y = std::cosh(ef) * std::cos(a);
+ if (conjugate) {
+ y = -y;
+ }
+ conjugate = !conjugate;
+ k += !conjugate;
+ return k <= n / 2;
+ }
+};
+
+int main() {
+ // std::unique_ptr<Scatter> s(new TestScatter());
+ // std::unique_ptr<Scatter> s(new ButterworthPoles(16));
+ std::unique_ptr<Scatter> s(new ChebyshevPoles(16, 0.01));
+
+ float x = 0.0f;
+ float y = 0.0f;
+ while (true) {
+ bool c = s->next(x, y);
+ printf("%f, %f\n", x, y);
+ if (!c) {
+ break;
+ }
+ }
+
+ return 0;
+}
diff --git a/test/scatter.gp b/test/scatter.gp
@@ -0,0 +1,7 @@
+set zeroaxis
+r = 2
+set xrange[-r:r]
+set yrange[-r:r]
+set grid
+
+plot "scatter.tmp" using 1:2:(sprintf("(%0.4f, %0.4f)", $1, $2)) with labels point pt 7 offset char 1,1 notitle
