Further Examples: SparseArray

Here are some rules suitable for constructing a sparse array.

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Here is a sparse array corresponding to rules.

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This constructs the same sparse array using one rule.

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This shows the ordinary representation of ss.

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This yields a sparse array in which unspecified elements are taken to have value instead of .

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The usual commands for matrices work with sparse arrays.

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This constructs a sparse array representing a banded matrix.

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The full form of a sparse array contains the necessary data stored in an efficient form.

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Evaluating the next two commands displays the structure of bb.

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This shows the structure of another sparse array.

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This defines the function BlockDiagonalMatrix which creates a block diagonal matrix from a list of matrices. For another efficient implementation see the Further Examples for PadRight.

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Here are four matrices.

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Here is the block diagonal matrix constructed from the four matrices.

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