BUILT-IN MATHEMATICA SYMBOL
Extract
Extract[expr, list]
extracts the part of expr at the position specified by list.
Extract[expr, {list1, list2, ...}]
extracts a list of parts of expr.
Extract[expr, list, h]
extracts parts of expr, wrapping each of them with head h before evaluation.
- Extract[expr, {i, j, ...}] is equivalent to Part[expr, i, j, ...].
- The position specifications used by Extract have the same form as those returned by Position, and used in functions such as MapAt and ReplacePart.
- You can use Extract[expr, ..., Hold] to extract parts without evaluation.
- If expr is a SparseArray object, Extract[expr, ...] extracts parts in the corresponding ordinary array.
Extract the second part from an expression:
| Out[1]= |  |
Extract a part nested in an expression:
| Out[2]= |  |
Extract parts from multiple positions:
| Out[3]= |  |
Extract the parts given by Position:
| Out[2]= |  |
| Out[3]= |  |
New in 3 | Last modified in 5
