public static Image <Rgba32> GenerateImage(CollectionBuffer cb, string type = "ACC1", string field = "AccX", string timeus = "TimeUS")
{
var bins = 10;
int N = 1 << bins;
var fft = new FFT2();
var acc1data = cb.GetEnumeratorType(type).ToArray();
log.Debug(type);
var firstsample = acc1data.Take(N);
var samplemin = double.Parse(firstsample.Min(a => a[timeus]));
var samplemax = double.Parse(firstsample.Max(a => a[timeus]));
log.Debug("samplemin " + samplemin + " samplemax " + samplemax);
var timedelta = samplemin - samplemax;
log.Debug(" timedelta " + timedelta);
double[] freqt = fft.FreqTable(N, (int)(1000 / (N / timedelta)));
// time , freq , [color] &freqcount
int totalsamples = acc1data.Count();
int count = totalsamples / N;
int done = 0;
// 50% overlap
int divisor = 2;
count *= divisor;
var img = new Image <Rgba32>(count, freqt.Length);
log.Debug("done and count ");
while (count > 1) // skip last part
{
var fftdata = acc1data.Skip((N * (done / divisor))).Take(N);
var time = fftdata.Skip(N / 2).First().time.ToString("o");
var fftanswerz = fft.rin(fftdata.Select(a => (double)(float)a.GetRaw(field)).ToArray(), (uint)bins);
//plotlydata.root.z.Add(fftanswerz.Select(a => a > 2 ? 0 : a).ToArray());
freqt.Select((y, i) => img[done, (freqt.Length - 1) - i] = GetColor(fftanswerz[i])).ToArray();
count--;
done++;
}
return(img);
}
public long GetLineNoFromTime(CollectionBuffer logdata, DateTime p1)
{
DateTime last = DateTime.MaxValue;
foreach (var dfItem in logdata.GetEnumeratorType(new string[] { "GPS", "GPS2" }))
{
// always forwards
if (dfItem.time >= p1)
{
return(dfItem.lineno);
}
last = dfItem.time;
}
if (last != DateTime.MaxValue)
{
return(long.MaxValue);
}
return(0);
}
public static void Create(string filein, string fileout, List <string> fmtList = null)
{
using (StreamReader tr = new StreamReader(filein))
using (CollectionBuffer logdata = new CollectionBuffer(tr.BaseStream))
{
List <string> colList = new List <string>();
Dictionary <string, int> colStart = new Dictionary <string, int>();
colStart.Add("GLOBAL", colList.Count);
colList.Add("GLOBAL_TimeMS");
foreach (var logformatValue in logdata.dflog.logformat.Values)
{
if (fmtList != null && !fmtList.Contains(logformatValue.Name))
{
continue;
}
colStart.Add(logformatValue.Name, colList.Count);
foreach (var field in logformatValue.FieldNames)
{
colList.Add(logformatValue.Name + "_" + field);
}
}
using (StreamWriter sr = new StreamWriter(fileout))
{
// header
foreach (var item in colList)
{
sr.Write(item + ",");
}
sr.WriteLine();
// lines
foreach (var dfitem in logdata.GetEnumeratorType(colStart.Keys.ToArray()))
{
if (dfitem.msgtype == "FMT")
{
continue;
}
var idx = 0;
StringBuilder sb = new StringBuilder();
sb.Append(dfitem.timems);
idx++;
sb.Append(',');
var start = colStart[dfitem.msgtype];
while (idx < start)
{
idx++;
sb.Append(',');
}
foreach (var item in dfitem.items.Skip(1))
{
sb.Append(item?.Trim());
idx++;
sb.Append(',');
}
sr.WriteLine(sb);
}
}
}
}
private void but_ISBH_Click(object sender, EventArgs e)
{
Utilities.FFT2 fft = new FFT2();
using (
OpenFileDialog ofd = new OpenFileDialog())
{
ofd.Filter = "*.log;*.bin|*.log;*.bin";
ofd.ShowDialog();
if (!File.Exists(ofd.FileName))
{
return;
}
var file = new CollectionBuffer(File.OpenRead(ofd.FileName));
int bins = (int)NUM_bins.Value;
int N = 1 << bins;
Color[] color = new Color[]
{ Color.Red, Color.Green, Color.Blue, Color.Black, Color.Violet, Color.Orange };
ZedGraphControl[] ctls = new ZedGraphControl[]
{
zedGraphControl1, zedGraphControl2, zedGraphControl3, zedGraphControl4, zedGraphControl5,
zedGraphControl6
};
// 3 imus * 2 sets of measurements(gyr/acc)
datastate[] alldata = new datastate[3 * 2];
for (int a = 0; a < alldata.Length; a++)
{
alldata[a] = new datastate();
}
// state cache
int Ns = 0;
int type = 0;
int instance = 0;
int sensorno = 0;
double smp_rate = 0;
foreach (var item in file.GetEnumeratorType(new string[] { "ISBH", "ISBD" }))
{
if (item.msgtype == null)
{
continue;
}
if (item.msgtype.StartsWith("ISBH"))
{
Ns = int.Parse(item.items[file.dflog.FindMessageOffset(item.msgtype, "N")],
CultureInfo.InvariantCulture);
type = int.Parse(item.items[file.dflog.FindMessageOffset(item.msgtype, "type")],
CultureInfo.InvariantCulture);
instance = int.Parse(item.items[file.dflog.FindMessageOffset(item.msgtype, "instance")],
CultureInfo.InvariantCulture);
sensorno = type * 3 + instance;
alldata[sensorno].sample_rate = double.Parse(item.items[file.dflog.FindMessageOffset(item.msgtype, "smp_rate")],
CultureInfo.InvariantCulture);
if (type == 0)
{
alldata[sensorno].type = "ACC" + instance.ToString();
}
if (type == 1)
{
alldata[sensorno].type = "GYR" + instance.ToString();
}
}
else if (item.msgtype.StartsWith("ISBD"))
{
var Nsdata = int.Parse(item.items[file.dflog.FindMessageOffset(item.msgtype, "N")],
CultureInfo.InvariantCulture);
if (Ns != Nsdata)
{
continue;
}
int offsetX = file.dflog.FindMessageOffset(item.msgtype, "x");
int offsetY = file.dflog.FindMessageOffset(item.msgtype, "y");
int offsetZ = file.dflog.FindMessageOffset(item.msgtype, "z");
int offsetTime = file.dflog.FindMessageOffset(item.msgtype, "TimeUS");
double time = double.Parse(item.items[offsetTime],
CultureInfo.InvariantCulture) / 1000.0;
if (time < alldata[sensorno].lasttime)
{
continue;
}
if (time != alldata[sensorno].lasttime)
{
alldata[sensorno].timedelta = alldata[sensorno].timedelta * 0.99 +
(time - alldata[sensorno].lasttime) * 0.01;
}
alldata[sensorno].lasttime = time;
item.items[offsetX].Split(new[] { ' ', '[', ']' }, StringSplitOptions.RemoveEmptyEntries).ForEach(aa => { alldata[sensorno].datax.Add(double.Parse(aa,
CultureInfo.InvariantCulture)); });
item.items[offsetY].Split(new[] { ' ', '[', ']' }, StringSplitOptions.RemoveEmptyEntries).ForEach(aa => { alldata[sensorno].datay.Add(double.Parse(aa,
CultureInfo.InvariantCulture)); });
item.items[offsetZ].Split(new[] { ' ', '[', ']' }, StringSplitOptions.RemoveEmptyEntries).ForEach(aa => { alldata[sensorno].dataz.Add(double.Parse(aa,
CultureInfo.InvariantCulture)); });
}
}
int controlindex = 0;
foreach (var sensordata in alldata)
{
if (sensordata.datax.Count <= N)
{
continue;
}
double samplerate = 0;
samplerate = sensordata.sample_rate;// Math.Round(1000 / sensordata.timedelta, 1);
double[] freqt = fft.FreqTable(N, (int)samplerate);
double[] avgx = new double[N / 2];
double[] avgy = new double[N / 2];
double[] avgz = new double[N / 2];
int totalsamples = sensordata.datax.Count;
int count = totalsamples / N;
int done = 0;
while (count > 1) // skip last part
{
var fftanswerx = fft.rin(sensordata.datax.Skip(N * done).Take(N).ToArray(), (uint)bins);
var fftanswery = fft.rin(sensordata.datay.Skip(N * done).Take(N).ToArray(), (uint)bins);
var fftanswerz = fft.rin(sensordata.dataz.Skip(N * done).Take(N).ToArray(), (uint)bins);
for (int b = 0; b < N / 2; b++)
{
if (freqt[b] < (double)NUM_startfreq.Value)
{
continue;
}
avgx[b] += fftanswerx[b] / (done + count);
avgy[b] += fftanswery[b] / (done + count);
avgz[b] += fftanswerz[b] / (done + count);
}
count--;
done++;
}
ZedGraph.PointPairList pplx = new ZedGraph.PointPairList(freqt, avgx);
ZedGraph.PointPairList pply = new ZedGraph.PointPairList(freqt, avgy);
ZedGraph.PointPairList pplz = new ZedGraph.PointPairList(freqt, avgz);
var curvex = new LineItem(sensordata.type + " x", pplx, color[0], SymbolType.None);
var curvey = new LineItem(sensordata.type + " y", pply, color[1], SymbolType.None);
var curvez = new LineItem(sensordata.type + " z", pplz, color[2], SymbolType.None);
ctls[controlindex].GraphPane.Legend.IsVisible = true;
ctls[controlindex].GraphPane.XAxis.Title.Text = "Freq Hz";
ctls[controlindex].GraphPane.YAxis.Title.Text = "Amplitude";
ctls[controlindex].GraphPane.Title.Text = "FFT " + sensordata.type + " - " +
Path.GetFileName(ofd.FileName) + " - " + samplerate +
"hz input";
ctls[controlindex].GraphPane.CurveList.Clear();
ctls[controlindex].GraphPane.CurveList.Add(curvex);
ctls[controlindex].GraphPane.CurveList.Add(curvey);
ctls[controlindex].GraphPane.CurveList.Add(curvez);
ctls[controlindex].Invalidate();
ctls[controlindex].AxisChange();
ctls[controlindex].GraphPane.XAxis.Scale.Max = samplerate / 2;
ctls[controlindex].Refresh();
controlindex++;
}
SetScale(ctls);
}
}
//FMT, 131, 43, IMU, IffffffIIf, TimeMS,GyrX,GyrY,GyrZ,AccX,AccY,AccZ,ErrG,ErrA,Temp
//FMT, 135, 43, IMU2, IffffffIIf, TimeMS,GyrX,GyrY,GyrZ,AccX,AccY,AccZ,ErrG,ErrA,Temp
//FMT, 149, 43, IMU3, IffffffIIf, TimeMS,GyrX,GyrY,GyrZ,AccX,AccY,AccZ,ErrG,ErrA,Temp
//FMT, 172, 23, ACC1, IIfff, TimeMS,TimeUS,AccX,AccY,AccZ
//FMT, 173, 23, ACC2, IIfff, TimeMS,TimeUS,AccX,AccY,AccZ
//FMT, 174, 23, ACC3, IIfff, TimeMS,TimeUS,AccX,AccY,AccZ
//FMT, 175, 23, GYR1, IIfff, TimeMS,TimeUS,GyrX,GyrY,GyrZ
//FMT, 176, 23, GYR2, IIfff, TimeMS,TimeUS,GyrX,GyrY,GyrZ
//FMT, 177, 23, GYR3, IIfff, TimeMS,TimeUS,GyrX,GyrY,GyrZ
private void myButton1_Click(object sender, EventArgs e)
{
Utilities.FFT2 fft = new FFT2();
using (OpenFileDialog ofd = new OpenFileDialog())
{
ofd.Filter = "*.log;*.bin|*.log;*.bin";
ofd.ShowDialog();
if (!File.Exists(ofd.FileName))
{
return;
}
var file = new CollectionBuffer(File.OpenRead(ofd.FileName));
int bins = (int)NUM_bins.Value;
int N = 1 << bins;
double[] datainGX = new double[N];
double[] datainGY = new double[N];
double[] datainGZ = new double[N];
double[] datainAX = new double[N];
double[] datainAY = new double[N];
double[] datainAZ = new double[N];
List <double[]> avg = new List <double[]>();
// 6
avg.Add(new double[N / 2]);
avg.Add(new double[N / 2]);
avg.Add(new double[N / 2]);
avg.Add(new double[N / 2]);
avg.Add(new double[N / 2]);
avg.Add(new double[N / 2]);
object[] datas = new object[] { datainGX, datainGY, datainGZ, datainAX, datainAY, datainAZ };
string[] datashead = new string[]
{ "GYR1-GyrX", "GYR1-GyrY", "GYR1-GyrZ", "ACC1-AccX", "ACC1-AccY", "ACC1-AccZ" };
Color[] color = new Color[]
{ Color.Red, Color.Green, Color.Black, Color.Violet, Color.Blue, Color.Orange };
ZedGraphControl[] ctls = new ZedGraphControl[]
{
zedGraphControl1, zedGraphControl2, zedGraphControl3, zedGraphControl4, zedGraphControl5,
zedGraphControl6
};
int samplecounta = 0;
int samplecountg = 0;
double lasttime = 0;
double timedelta = 0;
double[] freqt = null;
double samplerate = 0;
foreach (var item in file.GetEnumeratorType(new string[] { "ACC1", "GYR1" }))
{
if (item.msgtype == "ACC1")
{
int offsetAX = file.dflog.FindMessageOffset("ACC1", "AccX");
int offsetAY = file.dflog.FindMessageOffset("ACC1", "AccY");
int offsetAZ = file.dflog.FindMessageOffset("ACC1", "AccZ");
int offsetTime = file.dflog.FindMessageOffset("ACC1", "TimeUS");
double time = double.Parse(item.items[offsetTime],
CultureInfo.InvariantCulture) / 1000.0;
timedelta = timedelta * 0.99 + (time - lasttime) * 0.01;
// we missed gyro data
if (samplecounta >= N)
{
continue;
}
datainAX[samplecounta] = double.Parse(item.items[offsetAX],
CultureInfo.InvariantCulture);
datainAY[samplecounta] = double.Parse(item.items[offsetAY],
CultureInfo.InvariantCulture);
datainAZ[samplecounta] = double.Parse(item.items[offsetAZ],
CultureInfo.InvariantCulture);
samplecounta++;
lasttime = time;
}
else if (item.msgtype == "GYR1")
{
int offsetGX = file.dflog.FindMessageOffset("GYR1", "GyrX");
int offsetGY = file.dflog.FindMessageOffset("GYR1", "GyrY");
int offsetGZ = file.dflog.FindMessageOffset("GYR1", "GyrZ");
int offsetTime = file.dflog.FindMessageOffset("ACC1", "TimeUS");
double time = double.Parse(item.items[offsetTime],
CultureInfo.InvariantCulture) / 1000.0;
// we missed accel data
if (samplecountg >= N)
{
continue;
}
datainGX[samplecountg] = double.Parse(item.items[offsetGX],
CultureInfo.InvariantCulture);
datainGY[samplecountg] = double.Parse(item.items[offsetGY],
CultureInfo.InvariantCulture);
datainGZ[samplecountg] = double.Parse(item.items[offsetGZ],
CultureInfo.InvariantCulture);
samplecountg++;
}
if (samplecounta >= N && samplecountg >= N)
{
int inputdataindex = 0;
foreach (var itemlist in datas)
{
var fftanswer = fft.rin((double[])itemlist, (uint)bins);
for (int b = 0; b < N / 2; b++)
{
avg[inputdataindex][b] += fftanswer[b] * (1.0 / (N / 2.0));
}
samplecounta = 0;
samplecountg = 0;
inputdataindex++;
}
}
}
if (freqt == null)
{
samplerate = Math.Round(1000 / timedelta, 1);
freqt = fft.FreqTable(N, (int)samplerate);
}
// 0 out all data befor cutoff
for (int inputdataindex = 0; inputdataindex < 6; inputdataindex++)
{
for (int b = 0; b < N / 2; b++)
{
if (freqt[b] < (double)NUM_startfreq.Value)
{
avg[inputdataindex][b] = 0;
continue;
}
break;
}
}
int controlindex = 0;
foreach (var item in avg)
{
ZedGraph.PointPairList ppl = new ZedGraph.PointPairList(freqt, item);
//double xMin, xMax, yMin, yMax;
var curve = new LineItem(datashead[controlindex], ppl, color[controlindex], SymbolType.None);
//curve.GetRange(out xMin, out xMax, out yMin, out yMax, true, false, ctls[c].GraphPane);
ctls[controlindex].GraphPane.Legend.IsVisible = false;
ctls[controlindex].GraphPane.XAxis.Title.Text = "Freq Hz";
ctls[controlindex].GraphPane.YAxis.Title.Text = "Amplitude";
ctls[controlindex].GraphPane.Title.Text = "FFT " + datashead[controlindex] + " - " +
Path.GetFileName(ofd.FileName) + " - " + samplerate +
"hz input";
ctls[controlindex].GraphPane.CurveList.Clear();
ctls[controlindex].GraphPane.CurveList.Add(curve);
ctls[controlindex].Invalidate();
ctls[controlindex].AxisChange();
ctls[controlindex].Refresh();
controlindex++;
}
SetScale(ctls);
}
}
private void but_fftimu_Click(object sender, EventArgs e)
{
Utilities.FFT2 fft = new FFT2();
using (
OpenFileDialog ofd = new OpenFileDialog())
{
ofd.Filter = "*.log;*.bin|*.log;*.bin";
ofd.ShowDialog();
if (!File.Exists(ofd.FileName))
{
return;
}
var file = new CollectionBuffer(File.OpenRead(ofd.FileName));
int bins = (int)NUM_bins.Value;
int N = 1 << bins;
Color[] color = new Color[] { Color.Red, Color.Green, Color.Blue, Color.Black, Color.Violet, Color.Orange };
ZedGraphControl[] ctls = new ZedGraphControl[]
{
zedGraphControl1, zedGraphControl2, zedGraphControl3, zedGraphControl4, zedGraphControl5,
zedGraphControl6
};
// 3 imus * 2 sets of measurements(gyr/acc)
datastate[] alldata = new datastate[3 * 2];
for (int a = 0; a < alldata.Length; a++)
{
alldata[a] = new datastate();
}
Log.DFLog dflog = new Log.DFLog();
foreach (var item in file.GetEnumeratorType(new string[] { "FMT", "IMU", "IMU2", "IMU3" }))
{
if (item.msgtype == null)
{
continue;
}
if (item.msgtype == "FMT")
{
dflog.FMTLine(file[item.lineno]);
continue;
}
if (item.msgtype.StartsWith("IMU"))
{
int sensorno = 0;
if (item.msgtype == "IMU")
{
sensorno = 0;
}
if (item.msgtype == "IMU2")
{
sensorno = 1;
}
if (item.msgtype == "IMU3")
{
sensorno = 2;
}
alldata[sensorno + 3].type = item.msgtype + " A";
int offsetAX = dflog.FindMessageOffset(item.msgtype, "AccX");
int offsetAY = dflog.FindMessageOffset(item.msgtype, "AccY");
int offsetAZ = dflog.FindMessageOffset(item.msgtype, "AccZ");
int offsetTime = dflog.FindMessageOffset(item.msgtype, "TimeUS");
double time = double.Parse(item.items[offsetTime]) / 1000.0;
if (time != alldata[sensorno + 3].lasttime)
{
alldata[sensorno + 3].timedelta = alldata[sensorno + 3].timedelta * 0.99 +
(time - alldata[sensorno + 3].lasttime) * 0.01;
}
alldata[sensorno + 3].lasttime = time;
alldata[sensorno + 3].datax.Add(double.Parse(item.items[offsetAX]));
alldata[sensorno + 3].datay.Add(double.Parse(item.items[offsetAY]));
alldata[sensorno + 3].dataz.Add(double.Parse(item.items[offsetAZ]));
//gyro
alldata[sensorno].type = item.msgtype + " G";
int offsetGX = dflog.FindMessageOffset(item.msgtype, "GyrX");
int offsetGY = dflog.FindMessageOffset(item.msgtype, "GyrY");
int offsetGZ = dflog.FindMessageOffset(item.msgtype, "GyrZ");
if (time != alldata[sensorno].lasttime)
{
alldata[sensorno].timedelta = alldata[sensorno].timedelta * 0.99 +
(time - alldata[sensorno].lasttime) * 0.01;
}
alldata[sensorno].lasttime = time;
alldata[sensorno].datax.Add(double.Parse(item.items[offsetGX]));
alldata[sensorno].datay.Add(double.Parse(item.items[offsetGY]));
alldata[sensorno].dataz.Add(double.Parse(item.items[offsetGZ]));
}
}
int controlindex = 0;
foreach (var sensordata in alldata)
{
if (sensordata.datax.Count <= N)
{
continue;
}
double samplerate = 0;
samplerate = Math.Round(1000 / sensordata.timedelta, 1);
double[] freqt = fft.FreqTable(N, (int)samplerate);
double[] avgx = new double[N / 2];
double[] avgy = new double[N / 2];
double[] avgz = new double[N / 2];
int totalsamples = sensordata.datax.Count;
int count = totalsamples / N;
int done = 0;
while (count > 1) // skip last part
{
var fftanswerx = fft.rin(sensordata.datax.Skip(N * done).Take(N).ToArray(), (uint)bins);
var fftanswery = fft.rin(sensordata.datay.Skip(N * done).Take(N).ToArray(), (uint)bins);
var fftanswerz = fft.rin(sensordata.dataz.Skip(N * done).Take(N).ToArray(), (uint)bins);
for (int b = 0; b < N / 2; b++)
{
if (freqt[b] < (double)NUM_startfreq.Value)
{
continue;
}
avgx[b] += fftanswerx[b] / (N / 2);
avgy[b] += fftanswery[b] / (N / 2);
avgz[b] += fftanswerz[b] / (N / 2);
}
count--;
done++;
}
ZedGraph.PointPairList pplx = new ZedGraph.PointPairList(freqt, avgx);
ZedGraph.PointPairList pply = new ZedGraph.PointPairList(freqt, avgy);
ZedGraph.PointPairList pplz = new ZedGraph.PointPairList(freqt, avgz);
var curvex = new LineItem(sensordata.type + " x", pplx, color[0], SymbolType.None);
var curvey = new LineItem(sensordata.type + " y", pply, color[1], SymbolType.None);
var curvez = new LineItem(sensordata.type + " z", pplz, color[2], SymbolType.None);
ctls[controlindex].GraphPane.Legend.IsVisible = true;
ctls[controlindex].GraphPane.XAxis.Title.Text = "Freq Hz";
ctls[controlindex].GraphPane.YAxis.Title.Text = "Amplitude";
ctls[controlindex].GraphPane.Title.Text = "FFT " + sensordata.type + " - " +
Path.GetFileName(ofd.FileName) + " - " + samplerate +
"hz input";
ctls[controlindex].GraphPane.CurveList.Clear();
ctls[controlindex].GraphPane.CurveList.Add(curvex);
ctls[controlindex].GraphPane.CurveList.Add(curvey);
ctls[controlindex].GraphPane.CurveList.Add(curvez);
ctls[controlindex].Invalidate();
ctls[controlindex].AxisChange();
ctls[controlindex].GraphPane.XAxis.Scale.Max = samplerate / 2;
ctls[controlindex].Refresh();
controlindex++;
}
}
}
public static void getdata(string file)
{
DFLog.DFItem? IMU = null;
DFLog.DFItem? ATT = null;
List <Vector3> gaccel = new List <Vector3>();
List <Vector3> vel = new List <Vector3>();
List <DateTime> timestamps = new List <DateTime>();
List <int> accel_indexes = new List <int>();
var dtsum = 0.0;
var dtcount = 0;
var cb = new CollectionBuffer(File.OpenRead(file));
foreach (var item in cb.GetEnumeratorType(new string[] { "GPS", "GPS2", "IMU", "ATT" }))
{
switch (item.msgtype)
{
case "GPS":
case "GPS2":
if ((Byte)item.GetRaw("Status") >= 3)
{
var v = new Vector3(
(Single)item.GetRaw("Spd") * Math.Cos(radians((Single)item.GetRaw("GCrs"))),
(Single)item.GetRaw("Spd") * Math.Sin(radians((Single)item.GetRaw("GCrs"))),
(Single)item.GetRaw("VZ"));
vel.Add(v);
timestamps.Add(item.time);
accel_indexes.Add(Math.Max(gaccel.Count - 1, 0));
}
break;
case "IMU":
if (ATT.HasValue)
{
gaccel.Add(earth_accel_df(item, ATT.Value));
if (IMU.HasValue)
{
var dt = item.time - IMU.Value.time;
dtsum += dt.TotalSeconds;
dtcount += 1;
}
IMU = item;
}
break;
case "ATT":
ATT = item;
break;
}
}
var imu_dt = dtsum / dtcount;
Console.WriteLine("{0} samples at dt {1}", vel.Count, imu_dt);
var besti = -1;
var besterr = 0.0;
List <double> delays = new List <double>();
List <double> errors = new List <double>();
foreach (var i in Enumerable.Range(0, 100))
{
var err = velocity_error(timestamps, vel, gaccel, accel_indexes, imu_dt, i);
if (err == null)
{
break;
}
errors.Add(err);
delays.Add(i * imu_dt);
if (besti == -1 || err < besterr)
{
besti = i;
besterr = err;
}
}
Console.WriteLine("Best {0} ({1}s) {2}", besti, besti * imu_dt, besterr);
}