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PadRight

Usage

PadRight[list, n]通过在右边用零填充list构造一个长度为 n的列表。
PadRight[list, n, x]通过重复元素 x 填充。
PadRight[list, n,   ,  , ...  ] 通过循环重复元素  填充
PadRight[list, n, padding, m] 留下一个放在右边的m个元素的边距。
PadRight[list,   ,  , ...  ]构成在层 i一个长度为  的嵌套列表。


Notes

PadRight[list, n, ... ]总是返回一个长度为 n的列表。
• 例如: PadRight[ a,b,c , 7]LongRightArrow . • 通过填充   ,  , ...  ,有效的规定循环重复  , 然后在它们顶部强加列表,列表的最后一个元素放在  的位置。
• Examples: PadRight[ a,b , 7,  x,y,z ]LongRightArrow .
PadRight[ a,b , 7,  x,y,z , 2]LongRightArrow .
• 参见 PadLeft的附加注解。
• 参见 Mathematica 全书: 1.8.6.
Further Examples

Padding a list

This makes a list of length  by padding to the right with x's.

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Using  gives padding on the left.

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Using an empty list you can see how a cyclic padding ends on the first element of the padding.

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Now the nonempty list is superimposed on the padding.

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Here the list is padded on the left by  elements.

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And here the first  elements of the list are dropped.

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This treats the list as cyclic.

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This has the same effect.

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Padding a matrix

This pads a  x  matrix to give  rows and  columns.

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This does the same thing, but uses a  x  block to provide the padding.

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This shifts the matrix down  row and to the right  columns.

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Padding graphics

Here is a nested list.

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This represents the list using Raster. (Raster starts from the lower-left corner so the picture seems upside-down.)

Evaluate the cell to see the graphic.

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Here the list is padded.

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Evaluate the cell to see the graphic.

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Here are two different paddings.

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Evaluate the cell to see the graphic.

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Evaluate the cell to see the graphic.

In[19]:=