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copied!<p>GPS altitude bounces around a lot, and each of these bounces looks like an ascent or descent. In my experience the barometer sensor bounces around a much narrower range.</p> <p>What you want to do is measure each climb (where a climb is defined as a constant increase in altitude), and sum the climbs to determine the total height climbed.</p> <p>With any sensor (GPS or baro) the altitude will bounce around a little and we don't want those little bounces to be registered as short descents and climbs. So when we are climbing, we want to ignore small dips in altitude.</p> <pre><code>double THRESHOLD = 10; Direction climbingOrDescending = Direction.NONE; double totalAscent = 0; double totalDescent = 0; double climbStart; double maxAltitude; double descentStart; double minAltitude; public void onSample(double sample) { if (climbingOrDescending == Direction.NONE) { // First sample climbingOrDescending = Direction.CLIMBING; // Arbitrary climbStart = sample; maxAltitude = sample; } else if (climbingOrDescending == Direction.CLIMBING) { if (sample > maxAltitude) { maxAltitude = sample; } else if (sample < (maxAltitude - THRESHOLD) ) { // bounces in sample that are smaller than THRESHOLD are ignored. If // the sample is far below maxAltitude... it is not a bounce, record // the climb and move to a descending state double altitudeGainedThisClimb = maxAltitude - climbStart; totalAscent += altitudeGainedThisClimb; // Prepare for descent. climbingOrDescending = Direction.DESCENDING; descentStart = maxAltitude; minAltitude = sample; } } else { // climbingOrDescending == DESCENDING // similar code goes here to measure descents } } public double getTotalAscent() { if (climbingOrDescending == Direction.CLIMBING) { return totalAscent + (maxAltitude - climbStart); } else { return totalAscent; } } </code></pre>

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