diff options
author | Bdale Garbee <bdale@gag.com> | 2013-01-12 10:57:22 -0700 |
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committer | Bdale Garbee <bdale@gag.com> | 2013-01-12 10:57:22 -0700 |
commit | 670034eef48d63cdaec8d271fa93da984ffe2ea9 (patch) | |
tree | 422713fba95404876049f785255942ce6d9c4afd /micropeak/MicroData.java | |
parent | 8c5ebaf88b459b09924753a8077393a7b0639133 (diff) | |
parent | d374d6be7eb040457f4df6c38b5d057f26ee741c (diff) |
Merge branch 'master' of ssh://git.gag.com/scm/git/fw/altos
Diffstat (limited to 'micropeak/MicroData.java')
-rw-r--r-- | micropeak/MicroData.java | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/micropeak/MicroData.java b/micropeak/MicroData.java new file mode 100644 index 00000000..71919ddb --- /dev/null +++ b/micropeak/MicroData.java @@ -0,0 +1,356 @@ +/* + * Copyright © 2012 Keith Packard <keithp@keithp.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +package org.altusmetrum.micropeak; + +import java.lang.*; +import java.io.*; +import java.util.*; +import org.altusmetrum.AltosLib.*; + +class MicroIterator implements Iterator<MicroDataPoint> { + int i; + MicroData data; + + public boolean hasNext() { + return i < data.pressures.length; + } + + public MicroDataPoint next() { + return new MicroDataPoint(data, i++); + } + + public MicroIterator (MicroData data) { + this.data = data; + i = 0; + } + + public void remove() { + } +} + +class MicroIterable implements Iterable<MicroDataPoint> { + + MicroData data; + + public Iterator<MicroDataPoint> iterator() { + return new MicroIterator(data); + } + + public MicroIterable(MicroData data) { + this.data = data; + } +} + +public class MicroData { + public int ground_pressure; + public int min_pressure; + public int[] pressures; + private double time_step; + private double ground_altitude; + private ArrayList<Integer> bytes; + String name; + + + class FileEndedException extends Exception { + } + + class NonHexcharException extends Exception { + } + + class InvalidCrcException extends Exception { + } + + private int getc(InputStream f) throws IOException, FileEndedException { + int c = f.read(); + + if (c == -1) + throw new FileEndedException(); + bytes.add(c); + return c; + } + + private int get_nonwhite(InputStream f) throws IOException, FileEndedException { + int c; + + for (;;) { + c = getc(f); + if (!Character.isWhitespace(c)) + return c; + } + } + + private int get_hexc(InputStream f) throws IOException, FileEndedException, NonHexcharException { + int c = get_nonwhite(f); + + if ('0' <= c && c <= '9') + return c - '0'; + if ('a' <= c && c <= 'f') + return c - 'a' + 10; + if ('A' <= c && c <= 'F') + return c - 'A' + 10; + throw new NonHexcharException(); + } + + private static final int POLY = 0x8408; + + private int log_crc(int crc, int b) { + int i; + + for (i = 0; i < 8; i++) { + if (((crc & 0x0001) ^ (b & 0x0001)) != 0) + crc = (crc >> 1) ^ POLY; + else + crc = crc >> 1; + b >>= 1; + } + return crc & 0xffff; + } + + int file_crc; + + private int get_hex(InputStream f) throws IOException, FileEndedException, NonHexcharException { + int a = get_hexc(f); + int b = get_hexc(f); + + int h = (a << 4) + b; + + file_crc = log_crc(file_crc, h); + return h; + } + + private boolean find_header(InputStream f) throws IOException { + try { + for (;;) { + if (get_nonwhite(f) == 'M' && get_nonwhite(f) == 'P') + return true; + } + } catch (FileEndedException fe) { + return false; + } + } + + private int get_32(InputStream f) throws IOException, FileEndedException, NonHexcharException { + int v = 0; + for (int i = 0; i < 4; i++) { + v += get_hex(f) << (i * 8); + } + return v; + } + + private int get_16(InputStream f) throws IOException, FileEndedException, NonHexcharException { + int v = 0; + for (int i = 0; i < 2; i++) { + v += get_hex(f) << (i * 8); + } + return v; + } + + private int swap16(int i) { + return ((i << 8) & 0xff00) | ((i >> 8) & 0xff); + } + + public boolean crc_valid; + + int mix_in (int high, int low) { + return high - (high & 0xffff) + low; + } + + boolean closer (int target, int a, int b) { + return Math.abs (target - a) < Math.abs(target - b); + } + + public double altitude(int i) { + return AltosConvert.pressure_to_altitude(pressures[i]); + } + + public Iterable<MicroDataPoint> points() { + return new MicroIterable(this); + } + + int fact(int n) { + if (n == 0) + return 1; + return n * fact(n-1); + } + + int choose(int n, int k) { + return fact(n) / (fact(k) * fact(n-k)); + } + + + public double avg_altitude(int center, int dist) { + int start = center - dist; + int stop = center + dist; + + if (start < 0) + start = 0; + if (stop >= pressures.length) + stop = pressures.length - 1; + + double sum = 0; + double div = 0; + + int n = dist * 2; + + for (int i = start; i <= stop; i++) { + int k = i - (center - dist); + int c = choose (n, k); + + sum += c * pressures[i]; + div += c; + } + + double pres = sum / div; + + double alt = AltosConvert.pressure_to_altitude(pres); + return alt; + } + + public double pressure(int i) { + return pressures[i]; + } + + public double height(int i) { + return altitude(i) - ground_altitude; + } + + public double apogee_pressure() { + return min_pressure; + } + + public double apogee_altitude() { + return AltosConvert.pressure_to_altitude(apogee_pressure()); + } + + public double apogee_height() { + return apogee_altitude() - ground_altitude; + } + + static final int speed_avg = 3; + static final int accel_avg = 5; + + private double avg_speed(int center, int dist) { + if (center == 0) + return 0; + + double ai = avg_altitude(center, dist); + double aj = avg_altitude(center - 1, dist); + double s = (ai - aj) / time_step; + + return s; + } + + public double speed(int i) { + return avg_speed(i, speed_avg); + } + + public double acceleration(int i) { + if (i == 0) + return 0; + return (avg_speed(i, accel_avg) - avg_speed(i-1, accel_avg)) / time_step; + } + + public double time(int i) { + return i * time_step; + } + + public void save (OutputStream f) throws IOException { + for (int c : bytes) + f.write(c); + f.write('\n'); + } + + public void export (Writer f) throws IOException { + PrintWriter pw = new PrintWriter(f); + pw.printf(" Time, Press(Pa), Height(m), Height(f), Speed(m/s), Speed(mph), Speed(mach), Accel(m/s²), Accel(ft/s²), Accel(g)\n"); + for (MicroDataPoint point : points()) { + pw.printf("%6.3f,%10.0f,%10.1f,%10.1f,%11.2f,%11.2f,%12.4f,%12.2f,%13.2f,%10.4f\n", + point.time, + point.pressure, + point.height, + AltosConvert.meters_to_feet(point.height), + point.speed, + AltosConvert.meters_to_mph(point.speed), + AltosConvert.meters_to_mach(point.speed), + point.accel, + AltosConvert.meters_to_feet(point.accel), + AltosConvert.meters_to_g(point.accel)); + } + } + + public void set_name(String name) { + this.name = name; + } + + public MicroData (InputStream f, String name) throws IOException, InterruptedException { + this.name = name; + bytes = new ArrayList<Integer>(); + if (!find_header(f)) + throw new IOException("No MicroPeak data header found"); + try { + file_crc = 0xffff; + ground_pressure = get_32(f); + min_pressure = get_32(f); + int nsamples = get_16(f); + pressures = new int[nsamples + 1]; + + ground_altitude = AltosConvert.pressure_to_altitude(ground_pressure); + int cur = ground_pressure; + pressures[0] = cur; + for (int i = 0; i < nsamples; i++) { + int k = get_16(f); + int same = mix_in(cur, k); + int up = mix_in(cur + 0x10000, k); + int down = mix_in(cur - 0x10000, k); + + if (closer (cur, same, up)) { + if (closer (cur, same, down)) + cur = same; + else + cur = down; + } else { + if (closer (cur, up, down)) + cur = up; + else + cur = down; + } + + pressures[i+1] = cur; + } + + int current_crc = swap16(~file_crc & 0xffff); + int crc = get_16(f); + + crc_valid = crc == current_crc; + + time_step = 0.192; + } catch (FileEndedException fe) { + throw new IOException("File Ended Unexpectedly"); + } catch (NonHexcharException ne) { + throw new IOException("Non hexadecimal character found"); + } + } + + public MicroData() { + ground_pressure = 101000; + min_pressure = 101000; + pressures = new int[1]; + pressures[0] = 101000; + } + +} |