PadLeft

PadLeft[list, n]
makes a list of length n by padding list with zeros on the left.

PadLeft[list, n, x]
pads by repeating the element x.

PadLeft[list, n, {x1, x2, ...}]
pads by cyclically repeating the elements .

PadLeft[list, n, padding, m]
leaves a margin of m elements of padding on the right.

PadLeft[list, {n1, n2, ...}]
makes a nested list with length at level i.

PadLeft[list]
pads a ragged array list with zeros to make it full.

DetailsDetails

  • PadLeft[list, n, ...] always returns a list of length n, except in some special cases where padding is .
  • With padding , cyclic repetitions of the are effectively laid down and then the list is superimposed on top of them, with the last element of the list lying on an occurrence of . »
  • PadLeft[list, n, padding, -m] truncates the last m elements of list.
  • A margin of Round[(n-Length[list])/2] effectively centers list.
  • PadLeft[list, n, list] effectively treats list as cyclic.
  • PadLeft[list, n, {xlist}] can be used to repeat an individual element that is itself a list.
  • PadLeft[{}, n, {x1, x2, ...}] repeats the sequence of as many times as fit in a list of length n.
  • PadLeft[list, {n1, n2, ...}] creates a full array with dimensions even if list is ragged. »
  • PadLeft[list, Automatic, x] pads with x to make a full array.
  • Negative specify to pad on the right.
  • PadLeft[list, {n1, n2}, {{x11, x12, ...}, {x21, ...}, ...}] pads by repeating the block of .
  • PadLeft[list, {n1, n2, ...}, list] effectively treats list as cyclic in every dimension.
  • PadLeft[list, {n1, n2, ...}, padding, {m1, m2, ...}] uses margin at level i.
  • The object list need not have head List.
  • PadLeft can be used on SparseArray objects.

ExamplesExamplesopen allclose all

Basic Examples (6)Basic Examples (6)

Pad with to make the list be of length 10:

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Pad with :

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Pad by repeating :

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Leave margin on the right:

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Pad to make a 3×5 array:

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Pad to make a full array:

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New in 4 | Last modified in 6
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