diff options
| author | Keith Packard <keithp@keithp.com> | 2013-01-10 21:48:12 -0800 | 
|---|---|---|
| committer | Keith Packard <keithp@keithp.com> | 2013-01-10 21:48:12 -0800 | 
| commit | 1ed6b13e87c1cc2d6618b6ba3a293ea6e3b5752e (patch) | |
| tree | 10adf6f3c6b6c1ed2bf7540a9972fe72253cfa81 /micropeak/MicroData.java | |
| parent | acff2f466031fd1a8533fc315411c3734a8bacc6 (diff) | |
| parent | d409417ff8e9ed9d406bf1c04542a4ecb574768b (diff) | |
Merge remote-tracking branch 'origin/micropeak-logging'
Diffstat (limited to 'micropeak/MicroData.java')
| -rw-r--r-- | micropeak/MicroData.java | 344 | 
1 files changed, 344 insertions, 0 deletions
| diff --git a/micropeak/MicroData.java b/micropeak/MicroData.java new file mode 100644 index 00000000..f1204e11 --- /dev/null +++ b/micropeak/MicroData.java @@ -0,0 +1,344 @@ +/* + * 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; +	} + +	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; +	} +	 +} | 
