Beispiel #1
0
        /// <summary>
        /// Transpose <paramref name="source"/>.
        /// </summary>
        /// <typeparam name="T">Type of element of the nested <see cref="IEnumerable{T}"/>.</typeparam>
        /// <param name="source">Sequence which will be transposed.</param>
        /// <param name="mode">How non-uniform sequences are handled.</param>
        /// <returns>Transposed <paramref name="source"/>.</returns>
        public static List <T[]> Transpose <T>(this IList <IList <T> > source, TransposeMode mode = TransposeMode.ErrorOnMissing)
        {
            if (source is null)
            {
                throw new ArgumentNullException(nameof(source));
            }
            if (source.Count == 0)
            {
                return(new List <T[]>());
            }

            List <T[]> lines = new List <T[]>();

            for (int j = 0; ; j++)
            {
                T[]  line = new T[source.Count];
                bool flag = false;
                for (int i = 0; i < source.Count; i++)
                {
                    bool value = j < source[i].Count;
                    flag |= value;
                    if (value)
                    {
                        line[i] = source[i][j];
                    }
                    else
                    {
                        switch (mode)
                        {
                        case TransposeMode.StripOnMissing:
                            return(lines);

                        case TransposeMode.DefaultOnMissing:
                            line[i] = default;
                            break;
                        }
                    }
                }
                if (flag)
                {
                    if (mode == TransposeMode.ErrorOnMissing)
                    {
                        throw new ArgumentOutOfRangeException("All nested enumerators must have same count.", nameof(source));
                    }
                    lines.Add(line);
                }
                else
                {
                    break;
                }
            }

            return(lines);
        }
Beispiel #2
0
        /// <summary>
        /// Transpose <paramref name="source"/>.
        /// </summary>
        /// <typeparam name="T">Type of element of the nested <see cref="IEnumerable{T}"/>.</typeparam>
        /// <param name="source">Sequence which will be transposed.</param>
        /// <param name="mode">How non-uniform sequences are handled.</param>
        /// <returns>Transposed <paramref name="source"/>.</returns>
        public static IEnumerable <IEnumerable <T> > Transpose <T>(this IEnumerable <IEnumerable <T> > source, TransposeMode mode = TransposeMode.ErrorOnMissing)
        {
            // https://stackoverflow.com/a/10555037/7655838 from https://stackoverflow.com/questions/10554866/how-do-you-transpose-dimensions-in-a-2d-collection-using-linq
            if (source is null)
            {
                throw new ArgumentNullException(nameof(source));
            }

            return(Work());

            IEnumerable <IEnumerable <T> > Work()
            {
                if (!source.Any())
                {
                    yield break;
                }

                IEnumerator <T>[] enumerators = source.Select(t => t.GetEnumerator()).ToArray();
                try
                {
                    T[] line = new T[enumerators.Length];
                    while (true)
                    {
                        bool atLeastOneTrue = false;
                        bool allTrue        = true;
                        for (int i = 0; i < enumerators.Length; i++)
                        {
                            bool value = enumerators[i].MoveNext();
                            atLeastOneTrue |= value;
                            allTrue        &= value;
                            if (value)
                            {
                                line[i] = enumerators[i].Current;
                            }
                            else
                            {
                                switch (mode)
                                {
                                case TransposeMode.StripOnMissing:
                                    yield break;

                                case TransposeMode.DefaultOnMissing:
                                    line[i] = default;
                                    break;
                                }
                            }
                        }
                        if (atLeastOneTrue)
                        {
                            if (mode == TransposeMode.ErrorOnMissing && !allTrue)
                            {
                                throw new ArgumentOutOfRangeException("All nested enumerators must have same count.", nameof(source));
                            }
                            else
                            {
                                yield return(line);
                            }
                        }
                        else
                        {
                            break;
                        }
                    }
                }
                finally
                {
                    for (int i = 0; i < enumerators.Length; i++)
                    {
                        enumerators[i].Dispose();
                    }
                }
            }
        }