Drop: Difference between revisions
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Miraheze>Marshall (Created page with "Drop (↓) is a primitive function which removes part of each axis of an array. The removed portions are exactly those that Take would include in its result. Drop...") |
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Each axis with a matching left argument element <code>d</code> is modified to remove <code>|d</code> indices, or all of them if <code>|d</code> is larger than the length of the axis. Indices are removed starting from the beginning if <code>d</code> is positive and starting from the end if it is negative (if <code>d</code> is 0, then no indices are removed). Equivalently, for an axis of length <code>l</code>, <code>l-l⌊|d</code> axes are retained—not dropped—from the axis starting from the opposite side: the end if <code>d</code> is positive and the beginning otherwise. If <code>|d</code> is greater than or equal to <code>l</code> for any axis, then the result is [[empty]] and shares a [[prototype]] with the argument. | Each axis with a matching left argument element <code>d</code> is modified to remove <code>|d</code> indices, or all of them if <code>|d</code> is larger than the length of the axis. Indices are removed starting from the beginning if <code>d</code> is positive and starting from the end if it is negative (if <code>d</code> is 0, then no indices are removed). Equivalently, for an axis of length <code>l</code>, <code>l-l⌊|d</code> axes are retained—not dropped—from the axis starting from the opposite side: the end if <code>d</code> is positive and the beginning otherwise. If <code>|d</code> is greater than or equal to <code>l</code> for any axis, then the result is [[empty]] and shares a [[prototype]] with the argument. | ||
== APL Model == | === APL Model === | ||
Drop can be modelled using Take with a complementary length: | Drop can be modelled using Take with a complementary length: | ||