Both natural and artificial trees are used as Christmas trees. Christmas tree - Natural trees. The best species for use are species of fir (Abies), which have the major benefit of not shedding the needles when they dry out, as well as good foliage colour and scent; but species in other genera are also used. Commonly used species in northern Europe (including the UK) are: Silver Fir Abies alba (the original species) Nordmann Fir Abies nordmanniana (as in the photo) ...

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Christmas tree, Christmas tree - Types of trees used, Christmas tree - Natural trees, Christmas tree - Artificial trees, Christmas tree - Decoration and ornaments, Christmas tree - Tree mats and skirts, Christmas tree - Flocking, Christmas tree - Care and disposal of natural trees, Christmas tree - History, Christmas tree - Name controversy, Christmas tree - Usage controversy

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The basic parts of a tree are the roots, trunk(s), branches, twigs and leaves. Tree stems consist mainly of support and transport tissues (xylem and phloem). Wood consists of xylem cells, and bark is made of phloem and other tissues external to the vascular cambium. Trees may be broadly grouped into exogenous and endogenous trees according to the way in which their stem diameter increases. Exogenous trees, which comprise the great majority of modern trees (all conifers, and all broadleaf trees), grow by the ...

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Tree, Tree - Classifications, Tree - Morphology, Tree - Champion trees, Tree - Major tree genera, Tree - Flowering plants Magnoliophyta; angiosperms, Tree - Conifers Pinophyta; softwood trees, Tree - Ginkgos Ginkgophyta, Tree - Cycads Cycadophyta, Tree - Ferns Pterophyta, Tree - Life stages, Tree - Bibliography

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Trees in mythology - Trees of cosmic significance. Tree of Life (Abrahamic Mythology, Cabala/Jewish mysticism) Tree of Knowledge of Good and Evil (Abrahamic Mythology) Yggdrasil (Norse mythology) Austras Koks (Latvian mythology) Deciduous Trees Falling off or shed at a specific season or stage of growth Many trees of life are considered to be deciduous. The Norse world tree Yggdrasil is an ash tree. In Chinese mythology, t ...

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Trees in mythology, Trees in mythology - Examples, Trees in mythology - Trees of cosmic significance, Trees in mythology - Mythical creatures or deities relating to trees, Trees in mythology - Miscellaneous, Trees in mythology - Resources, Trees in mythology - Fictional trees inspired by myth

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A tree is a plant form and trees occur in many different orders and families of plants. Trees thus show a wide variety of growth form, leaf type and shape, bark characteristics, reproductive structures, etc. The earliest trees were tree ferns and horsetails, which grew in vast forests in the Carboniferous Period; tree ferns still survive, but the only surviving horsetails are not of tree form. Later, in the Triassic Period, conifers, ginkgos, cycads and other gymnosperms appeared, and subsequently flowering plants in the Cretaceous Pe ...

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Tree, Tree - Classifications, Tree - Morphology, Tree - Champion trees, Tree - Major tree genera, Tree - Flowering plants Magnoliophyta; angiosperms, Tree - Conifers Pinophyta; softwood trees, Tree - Ginkgos Ginkgophyta, Tree - Cycads Cycadophyta, Tree - Ferns Pterophyta, Tree - Life stages, Tree - Bibliography

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A binary tree is a rooted tree in which every node has at most two children. A full binary tree is a tree in which every node has zero or two children. A perfect binary tree is a complete binary tree in which leaves (vertices with zero children) are at the same depth (distance from the root, also called height). Sometimes the perfect binary tree is called the complete binary tree. Some others define a complete binary tree to be a full binary tre ...

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Binary tree, Binary tree - Definitions for rooted trees, Binary tree - Types of binary tree, Binary tree - Definition in graph theory, Binary tree - Methods for storing binary trees, Binary tree - Methods of iterating over binary trees, Binary tree - Pre-order in-order and post-order traversal, Binary tree - Depth-first order, Binary tree - Breadth-first order, Binary tree - Encodings, Binary tree - Succinct encodings, Binary tree - Encoding n-ary trees as binary trees

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There are many ways of visually representing tree structures. Almost always, these boil down to variations, or combinations, of a few basic styles: Classical node-link diagrams, that connect nodes together with line segments: encyclopedia / \ science culture / \ art craft Nested sets that use enclosure/containment to show parenthood (for an ...

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Tree structure, Tree structure - Examples of tree structures, Tree structure - Representing trees, Tree structure - Related terms

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The life cycles of trees, especially conifers, are divided into the following stages in forestry for survey and documentation purposes: Seed Seedling: the above ground part of the embryo that sprout from the seed Sapling: After the seedling reaches 1m tall, and until it reaches 7cm in stem diameter Pole: young trees from 7-30cm diameter Mature tree: over 30cm diameter, reproductive years begin Old tree: dominate old growth forest; height growth slows greatly, with majority of producti ...

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Tree, Tree - Classifications, Tree - Morphology, Tree - Champion trees, Tree - Major tree genera, Tree - Flowering plants Magnoliophyta; angiosperms, Tree - Conifers Pinophyta; softwood trees, Tree - Ginkgos Ginkgophyta, Tree - Cycads Cycadophyta, Tree - Ferns Pterophyta, Tree - Life stages, Tree - Bibliography

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The Christmas tree is often explained as a Christianization of the ancient pagan idea that the evergreen tree represents a celebration of the renewal of life. In Roman mosaics from what is today Tunisia, showing the mythic triumphant return from India of the Greek god of wine and male fertility, Dionysus (dubbed by some modern scholars as a life-death-rebirth deity), the god carries a tapering coniferous tree. Medieval legends, nevertheless, tended to concentrate more on the miraculous "flowering" of trees at Christmas time. A branch of flowering Glastonbury thorn is still sent annually for the Quee ...

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Christmas tree, Christmas tree - Types of trees used, Christmas tree - Natural trees, Christmas tree - Artificial trees, Christmas tree - Decoration and ornaments, Christmas tree - Tree mats and skirts, Christmas tree - Flocking, Christmas tree - Care and disposal of natural trees, Christmas tree - History, Christmas tree - Name controversy, Christmas tree - Usage controversy

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A directed edge connects the parent to the child. A node that has no children is called a leaf. The depth of a node n is the length of the path from the root to the node. The set of all nodes at a given depth is sometimes called a level of the tree. The height of a node n is the length of the path from the node n to its furthest leaf. Nodes that share parents are called siblings. If a path exists from node p to node q, then p is an ancestor of q and q is a descendant of p. The size of ...

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Binary tree, Binary tree - Definitions for rooted trees, Binary tree - Types of binary tree, Binary tree - Definition in graph theory, Binary tree - Methods for storing binary trees, Binary tree - Methods of iterating over binary trees, Binary tree - Pre-order in-order and post-order traversal, Binary tree - Depth-first order, Binary tree - Breadth-first order, Binary tree - Encodings, Binary tree - Succinct encodings, Binary tree - Encoding n-ary trees as binary trees

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B-tree - Search. Search is performed in the typical manner, analogous to that in a binary search tree. Starting at the root, the tree is traversed top to bottom, choosing the child pointer whose separation values are on either side of the value that is being searched. Binary search is typically used within nodes to determine this location B-tree - Insertion. For a node to be in an illegal state, it must contain a number of elements which are outside of the acceptable range. ...

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B-tree, B-tree - Node structures, B-tree - Algorithms, B-tree - Search, B-tree - Insertion, B-tree - Deletion, B-tree - Notes

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A suffix tree for a string S of length n can be built in Θ(n) time, if the alphabet is viewed as a constant. Otherwise, the construction time depends on the implementation. Assume that a suffix tree has been built for the string S, or that a generalised suffix tree has been built for the set of strings D={S1, S2, ..., Sd} of total length n = |S1| + |S2| + ... + |Sd|. A ...

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Suffix tree, Suffix tree - Functionality, Suffix tree - Uses, Suffix tree - Description

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The Joshua Tree - Water and Desert. Numerous aspects of the album emphasize water and the desert. To begin with, the cover photograph is a black-and-white photo of the band at Joshua Tree National Park in the desert of California, taken by the band's longtime photographer Anton Corbijn. Throughout the album, there are numerous explicit lyrical references to water and desert. Specifically, there are 46 references to the words rain, raining, rainin', rainfall, flood, water, well, sea, ocean, and river. Also, there ...

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The Joshua Tree, The Joshua Tree - Themes, The Joshua Tree - Water and Desert, The Joshua Tree - America, The Joshua Tree - Loss, The Joshua Tree - Greg Carroll, The Joshua Tree - The Joshua Tree, The Joshua Tree - Summary, The Joshua Tree - Track listing, The Joshua Tree - Personnel, The Joshua Tree - Charting singles

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In machine learning, a decision tree is a predictive model; that is, a mapping of observations about an item to conclusions about the item's target value. Each inner node corresponds to variable; an arc to a child represents a possible value of that variable. A leaf represents the predicted value of target variable given the values of the variables represented by the path from the root. The machine learning technique for inducing a decision tree from data is called decision tree learning, ...

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Decision tree, Decision tree - General, Decision tree - Types, Decision tree - Practical example, Decision tree - Formulas, Decision tree - Gini impurity, Decision tree - Entropy, Decision tree - Decision tree advantages, Decision tree - Extending decision trees with decision graphs, Decision tree - External sources

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Decision tree has two other names: Regression tree approximate real-valued functions instead of being used for classification tasks. (e.g. estimate the price of a house or a patient’s length of stay in a hospital) Classification tree, if the Y is a categorical variable like: sex (male or female), the result of a game (lose or win). ...

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Decision tree, Decision tree - General, Decision tree - Types, Decision tree - Practical example, Decision tree - Formulas, Decision tree - Gini impurity, Decision tree - Entropy, Decision tree - Decision tree advantages, Decision tree - Extending decision trees with decision graphs, Decision tree - External sources

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These tips will ensure the tree will stay fresh for several weeks. When transporting the tree, protect it from wind and road salts by covering it with plastic. If decoration is not planned immediately, store the tree in a cool environment protected from the sun and wind. If possible, the night before decorating, bring the tree into a partially heated area to allow it to adjust gradually to temperature changes. Before taking your tree inside, gently bang the tree on its stump several times to dislodge any loose ...

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Christmas tree, Christmas tree - Types of trees used, Christmas tree - Natural trees, Christmas tree - Artificial trees, Christmas tree - Decoration and ornaments, Christmas tree - Tree mats and skirts, Christmas tree - Flocking, Christmas tree - Care and disposal of natural trees, Christmas tree - History, Christmas tree - Name controversy, Christmas tree - Usage controversy

Read more here: » Christmas tree: Encyclopedia II - Christmas tree - Care and disposal of natural trees

B-tree - Search. Search is performed in the typical manner, analogous to that in a binary search tree. Starting at the root, the tree is traversed top to bottom, choosing the child pointer whose separation values are on either side of the value that is being searched. Binary search is typically used within nodes to determine this location. B-tree - Insertion. For a node to be in an illegal state, it must contain a number of elements which are outside of the acceptable range.

B-tree, B-tree - Node structures, B-tree - Algorithms, B-tree - Search, B-tree - Insertion, B-tree - Deletion, B-tree - Notes

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Suppose L is the least number of children a node is allowed to have, while U is the greatest number. Then each node will always have between L and U children, inclusively, with one exception: the root node may have anywhere from 2 to U children inclusively. In other words, the root is exempt from the lower bound restriction, having a lower bound, 2, of its own. This allows the tree to hold small numbers of elements. The root having one child makes no sense, since the subtree attached to that c ...

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B-tree, B-tree - Node structures, B-tree - Algorithms, B-tree - Search, B-tree - Insertion, B-tree - Deletion, B-tree - Notes

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By the Tree was founded in Weatherford, Texas in 1997 by Chuck Dennie and Kevin Rhoads. As with most aspiring musical groups, By the Tree got their start playing a series of small venues — predominantly churches — throughout the southern and southwestern United States. Their near-constant touring cultivated a sizeable fan base. In 1999 they released two independent, self-produced CDs, which they sold at their concerts. By 2001, these two CDs had sold a combined 30,000 units, which more than recouped their production costs, and additionally brought them to the ...

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By the Tree, By the Tree - Overview, By the Tree - Current members, By the Tree - Former members, By the Tree - Discography, By the Tree - External link

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List of famous trees - Africa. Arbre du Ténéré, a very isolated tree in the Sahara region. List of famous trees - Asia. The Bodhi tree, a Sacred Fig tree under which Buddha is supposed to have been enlightened, at Bodh Gaya, India. The Sri Maha Bodhi tree, propagated from the Bodhi tree, planted in 288 BC at Anuradhapura, Sri Lanka. The 450 year-old giant banyan tree at Adyar in Chennai, Tamilnadu, India in the grounds of the Theosophical ...

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List of famous trees, List of famous trees - Real individual trees, List of famous trees - Africa, List of famous trees - Asia, List of famous trees - Europe, List of famous trees - North America, List of famous trees - Oceania, List of famous trees - Mythological and religious, List of famous trees - Fictional

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With a complete game tree, it is possible to "solve" the game-- that is to say, find a sequence of moves that either the first or second player can follow that will guarantee either a win or tie. The algorithm can be described recursively as follows. Color the final ply of the game tree so that all wins for player 1 are colored one way, all wins for player 2 are colored another way, and all ties are colored a third way. Look at the next ply up. If there exists a node colored opposite as the current player, col ...

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Game tree, Game tree - Solving Game Trees

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The Tiger tree hash is probably the most widely used form of hash tree. It uses a binary hash tree (two child nodes under each node), usually has a data block size of 1024-bytes and uses the cryptographically secure Tiger hash. Tiger tree hashes are used in the Gnutella2 p2p file sharing protocol and in file sharing applications like Direct Connect, BearShare, Shareaza and DC++. ...

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Hash tree, Hash tree - Tiger tree hash

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