altoslib: Create data file open helper in AltosLib

[fw/altos] / altoslib / AltosTimeSeries.java

diff --git a/altoslib/AltosTimeSeries.java b/altoslib/AltosTimeSeries.java
index 1d3d9a6c5185878fb6400412f400c23d2a831581..db33fafa56a088c1e05910229fb7029802da13c5 100644 (file)
--- a/altoslib/AltosTimeSeries.java
+++ b/altoslib/AltosTimeSeries.java
@@ -17,9 +17,9 @@ package org.altusmetrum.altoslib_11;
 import java.util.*;
 
 public class AltosTimeSeries implements Iterable<AltosTimeValue> {
-       public String           label;
-       public AltosUnits       units;
-       List<AltosTimeValue>    values;
+       public String                   label;
+       public AltosUnits               units;
+       ArrayList<AltosTimeValue>       values;
 
        public void add(AltosTimeValue tv) {
                values.add(tv);
@@ -33,6 +33,74 @@ public class AltosTimeSeries implements Iterable<AltosTimeValue> {
                return values.get(i);
        }
 
+       private double lerp(AltosTimeValue v0, AltosTimeValue v1, double t) {
+               /* degenerate case */
+               if (v0.time == v1.time)
+                       return (v0.value + v1.value) / 2;
+
+               return (v0.value * (v1.time - t) + v1.value * (t - v0.time)) / (v1.time - v0.time);
+       }
+
+       private int after_index(double time) {
+               int     lo = 0;
+               int     hi = values.size() - 1;
+
+               while (lo <= hi) {
+                       int mid = (lo + hi) / 2;
+
+                       if (values.get(mid).time < time)
+                               lo = mid + 1;
+                       else
+                               hi = mid - 1;
+               }
+               return lo;
+       }
+
+       /* Compute a value for an arbitrary time */
+       public double value(double time) {
+               int after = after_index(time);
+               double ret;
+
+               if (after == 0)
+                       ret = values.get(0).value;
+               else if (after == values.size())
+                       ret = values.get(after - 1).value;
+               else {
+                       AltosTimeValue b = values.get(after-1);
+                       AltosTimeValue a = values.get(after);
+                       ret = lerp(b, a, time);
+               }
+               return ret;
+       }
+
+       /* Find the value just before an arbitrary time */
+       public double value_before(double time) {
+               int after = after_index(time);
+
+               if (after == 0)
+                       return values.get(0).value;
+               return values.get(after-1).value;
+       }
+
+       /* Find the value just after an arbitrary time */
+       public double value_after(double time) {
+               int after = after_index(time);
+
+               if (after == values.size())
+                       return values.get(after-1).value;
+               return values.get(after).value;
+       }
+
+       public double time_of(double value) {
+               double  last = AltosLib.MISSING;
+               for (AltosTimeValue v : values) {
+                       if (v.value >= value)
+                               return v.time;
+                       last = v.time;
+               }
+               return last;
+       }
+
        public int size() {
                return values.size();
        }
@@ -41,24 +109,69 @@ public class AltosTimeSeries implements Iterable<AltosTimeValue> {
                return values.iterator();
        }
 
-       public double max() {
-               double max = AltosLib.MISSING;
+       public AltosTimeValue max() {
+               AltosTimeValue max = null;
+               for (AltosTimeValue tv : values)
+                       if (max == null || tv.value > max.value)
+                               max = tv;
+               return max;
+       }
+
+       public AltosTimeValue max(double start_time, double end_time) {
+               AltosTimeValue max = null;
                for (AltosTimeValue tv : values) {
-                       if (max == AltosLib.MISSING || tv.value > max)
-                               max = tv.value;
+                       if (start_time <= tv.time && tv.time <= end_time)
+                               if (max == null || tv.value > max.value)
+                                       max = tv;
                }
                return max;
        }
 
-       public double min() {
-               double min = AltosLib.MISSING;
+       public AltosTimeValue min() {
+               AltosTimeValue min = null;
+               for (AltosTimeValue tv : values) {
+                       if (min == null || tv.value < min.value)
+                               min = tv;
+               }
+               return min;
+       }
+
+       public AltosTimeValue min(double start_time, double end_time) {
+               AltosTimeValue min = null;
                for (AltosTimeValue tv : values) {
-                       if (min == AltosLib.MISSING || tv.value < min)
-                               min = tv.value;
+                       if (start_time <= tv.time && tv.time <= end_time)
+                               if (min == null || tv.value < min.value)
+                                       min = tv;
                }
                return min;
        }
 
+       public double average() {
+               double total = 0;
+               int count = 0;
+               for (AltosTimeValue tv : values) {
+                       total += tv.value;
+                       count++;
+               }
+               if (count == 0)
+                       return AltosLib.MISSING;
+               return total / count;
+       }
+
+       public double average(double start_time, double end_time) {
+               double total = 0;
+               int count = 0;
+               for (AltosTimeValue tv : values) {
+                       if (start_time <= tv.time && tv.time <= end_time) {
+                               total += tv.value;
+                               count++;
+                       }
+               }
+               if (count == 0)
+                       return AltosLib.MISSING;
+               return total / count;
+       }
+
        public AltosTimeSeries integrate(AltosTimeSeries integral) {
                double  value = 0.0;
                double  pvalue = 0.0;
@@ -74,7 +187,6 @@ public class AltosTimeSeries implements Iterable<AltosTimeValue> {
                        }
                        pvalue = v.value;
                        time = v.time;
-//                     System.out.printf("%g %g %g\n", time, v.value, value);
                        integral.add(time, value);
 
                }
@@ -144,13 +256,20 @@ public class AltosTimeSeries implements Iterable<AltosTimeValue> {
 
                        int     left = find_left(i, half_width);
                        int     right = find_right(i, half_width);
+
                        for (int j = left; j <= right; j++) {
                                double  j_time = values.get(j).time;
 
                                if (left_time <= j_time && j_time <= right_time) {
-                                       double  coeff = filter_coeff(j_time - center_time, width);
+                                       double  j_left = j == left ? left_time : values.get(j-1).time;
+                                       double  j_right = j == right ? right_time : values.get(j+1).time;
+                                       double  interval = (j_right - j_left) / 2.0;
+                                       double  coeff = filter_coeff(j_time - center_time, width) * interval;
+                                       double  value = values.get(j).value;
+                                       double  partial = value * coeff;
+
                                        total_coeff += coeff;
-                                       total_value += coeff * values.get(j).value;
+                                       total_value += partial;
                                }
                        }
                        if (total_coeff != 0.0)