예제 #1
0
 /// <summary>
 /// parse the fragment string, 
 /// "start=t1&end=t2&decimation=2" decimation is optional
 /// </summary>
 /// <param name="fragment"></param>
 /// <returns></returns>
 public static WaveFragment Parse(string fragment)
 {
     //"start=t1&end=t2&decimation=2&count=1000" decimation is optional
     if (fragment.StartsWith("#"))
     {
         fragment = fragment.Substring(1);
     }
     var sections = fragment.Split(new char[] { '&' });
     var result = new WaveFragment { DecimationFactor = 1, Start = 0, End = 0, Count = 0 };
     foreach (var sec in sections)
     {
         if (sec.Contains("start"))
         {
             result.Start = double.Parse(sec.Substring(6));
         }
         if (sec.Contains("end"))
         {
             result.End = double.Parse(sec.Substring(4));
         }
         if (sec.Contains("decimation"))
         {
             result.DecimationFactor = long.Parse(sec.Substring(11));
         }
         if (sec.Contains("count"))
         {
             result.Count = long.Parse(sec.Substring(6)) > 0 ? long.Parse(sec.Substring(6)) : 0;
         }
     }
     return result;
 }
예제 #2
0
        /// <summary>
        /// 使用Cursor读取大数据
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="signal"></param>
        /// <param name="fragment"></param>
        /// <returns></returns>
        public async Task<ICursor> GetCursorAsync<T>(Signal signal, string fragment)
        {
            //var waveSig = signal as FixedIntervalWaveSignal<T>;
            var waveSig = signal as FixedIntervalWaveSignal;
            if (waveSig == null)
            {
                throw new Exception(ErrorMessages.NotValidSignalError);
            }
            WaveFragment frag = null;
            try
            {
                frag = WaveFragment.Parse(fragment);
            }
            catch (Exception)
            {
                throw new Exception(ErrorMessages.NotValidSignalFragmentError);
            }
            //end smaller then start then read all
            if (frag.Start >= frag.End)
            {
                frag.Start = waveSig.StartTime;
                frag.End = waveSig.EndTime;
            }
            //calc the decimationfactor is count valid
            if (frag.Count > 0)
            {
                //todo can be optimized a little
                frag.DecimationFactor = (long)Math.Floor(((frag.End - frag.Start) / waveSig.SampleInterval + 1) / frag.Count);
            }
            if (frag.DecimationFactor < 1)
            {
                frag.DecimationFactor = 1;
            }

            var startIndex = (long)Math.Ceiling((frag.Start - waveSig.StartTime) / waveSig.SampleInterval);
            var count = (long)Math.Floor((frag.End - frag.Start) / waveSig.SampleInterval / frag.DecimationFactor) + 1;

            return await myStorageEngine.GetCursorAsync<T>(waveSig.Id, new List<long> { startIndex }, new List<long> { count }, new List<long> { frag.DecimationFactor });
        }
예제 #3
0
        /// <summary>
        /// format is "array"(default) or "complex" 
        /// review 这个下面很多代码和get curser重复了,可以修改
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="signal"></param>
        /// <param name="fragment">fragment: "start=t1&end=t2&decimation=2&count=1000" decimation is optional, if end is no bigger then start then return all</param>
        /// <param name="format">format is "array"(default) or "complex" </param>
        /// <returns></returns>
        public async Task<object> GetDataAsync<T>(Signal signal, string fragment, string format)
        {
            //var waveSig = signal as FixedIntervalWaveSignal<T>;
            var waveSig = signal as FixedIntervalWaveSignal;
            if (waveSig == null)
            {
                throw new Exception(ErrorMessages.NotValidSignalError);
            }
            WaveFragment frag = null;
            try
            {
                frag = WaveFragment.Parse(fragment);
            }
            catch (Exception)
            {
                throw new Exception("Fragment parse error!");
            }
            //end smaller then start then read all
            if (frag.Start >= frag.End)
            {
                frag.Start = waveSig.StartTime;
                frag.End = waveSig.EndTime;
            }
            if (frag.Start < waveSig.StartTime)
            {
                frag.Start = waveSig.StartTime;
            }
            if (frag.End > waveSig.EndTime)
            {
                frag.End = waveSig.EndTime;
            }
            //calc the decimationfactor is count valid
            if (frag.Count > 0)
            {
                //todo can be optimized a little
                frag.DecimationFactor = (long)Math.Floor(((frag.End - frag.Start) / waveSig.SampleInterval + 1) / frag.Count);
            }
            if (frag.DecimationFactor < 1)
            {
                frag.DecimationFactor = 1;
            }

            var startIndex = (long)Math.Ceiling((frag.Start - waveSig.StartTime) / waveSig.SampleInterval);
            var count = (long)Math.Floor((frag.End - frag.Start) / waveSig.SampleInterval / frag.DecimationFactor) + 1;

            ICursor<T> cursor = await myStorageEngine.GetCursorAsync<T>(waveSig.Id, new List<long> { startIndex }, new List<long> { count }, new List<long> { frag.DecimationFactor });
            List<T> resultArray = new List<T>();
            //防止读时越界 review cursor 目前一次只能读1000个点?
            while (cursor.LeftPoint > 1000)
            {
                resultArray.AddRange(await cursor.Read(1000));
            }
            if (cursor.LeftPoint > 0)
            {
                resultArray.AddRange(await cursor.Read(cursor.LeftPoint));
            }
            if (format == "complex")
            {
                return new FixedIntervalWaveComplex<T>
                {
                    Title = waveSig.Path,
                    Start = startIndex * waveSig.SampleInterval + waveSig.StartTime,
                    End = waveSig.StartTime + ((count - 1) * frag.DecimationFactor + startIndex) * waveSig.SampleInterval,
                    Count = count,
                    Data = resultArray,
                    DecimatedSampleInterval = waveSig.SampleInterval * frag.DecimationFactor,
                    OrignalSampleInterval = waveSig.SampleInterval,
                    DecimationFactor = frag.DecimationFactor,
                    StartIndex = startIndex,
                    Unit = waveSig.Unit
                };
            }
            else if (format == "point")
            {
                var points = new List<SignalPoint<T>>();
                // 计算首尾所需取的采样间隔(一致)、点数
                //bug review 这里是不是也有点重复?,我也没看懂,我大概的理解是,不管用户请求什么数据,都把全部的数据返回给用户,不过用户请求区域以外的数据,点数更加稀疏一些(100个点?)?这个逻辑和其他的读取不一样呀,有问题!!!
                long headtailDecimationFactor = 0;
                long headtailMaxCount = 100;
                if ((frag.Start - waveSig.StartTime) > (waveSig.EndTime - frag.End))
                {
                    headtailDecimationFactor = (long)Math.Floor(((frag.Start - waveSig.StartTime) / waveSig.SampleInterval + 1) / headtailMaxCount);
                }
                else
                {
                    headtailDecimationFactor = (long)Math.Floor(((waveSig.EndTime - frag.End) / waveSig.SampleInterval + 1) / headtailMaxCount);
                }
                if (headtailDecimationFactor < 1)
                {
                    headtailDecimationFactor = 1;
                }
                var headCount = (long)Math.Floor((frag.Start - waveSig.StartTime) / waveSig.SampleInterval / headtailDecimationFactor) + 1;
                var tailCount = (long)Math.Floor((waveSig.EndTime - frag.End) / waveSig.SampleInterval / headtailDecimationFactor) + 1;
                //添加前段概略点
                double x = waveSig.StartTime;
                if (headCount > 1)
                {
                    ICursor<T> headCursor = await myStorageEngine.GetCursorAsync<T>(waveSig.Id, new List<long> { 0 }, new List<long> { headCount }, new List<long> { headtailDecimationFactor });
                    //review 这里不应该用foreach,顺序不定,而且即使用循环也不太好,效率有点低,不过好像也没什么别的办法,最好还是不要生成x序列,太浪费服务器资源了,以后,以后我们前端最好还是不要用这个point
                    foreach (var data in await headCursor.Read(headCursor.LeftPoint))
                    {
                        points.Add(new SignalPoint<T>(x, data));
                        x += waveSig.SampleInterval * headtailDecimationFactor;
                    }
                }
                //添加中间详细点
                x = frag.Start;
                foreach (var data in resultArray)
                {
                    points.Add(new SignalPoint<T>(x, data));
                    x += waveSig.SampleInterval * frag.DecimationFactor;
                }
                //添加后段概略点
                if (tailCount > 1)
                {
                    ICursor<T> tailCursor = await myStorageEngine.GetCursorAsync<T>(waveSig.Id, new List<long> { 0 }, new List<long> { tailCount }, new List<long> { headtailDecimationFactor });
                    x = frag.End;
                    foreach (var data in await tailCursor.Read(tailCursor.LeftPoint))
                    {
                        points.Add(new SignalPoint<T>(x, data));
                        x += waveSig.SampleInterval * headtailDecimationFactor;
                    }
                }
                return points;
            }
            else
            {
                return resultArray;
            }
        }