考虑括号的拆分字符串 - R答案

【问题标题】：Split string considering brackets - R考虑括号的拆分字符串 - R
【发布时间】：2021-01-19 12:59:17
【问题描述】：

我想编辑R 中的字符串，同时考虑开括号和右括号。

字符向量是坐标系的WKT引用，如rgdal、sp中使用的，它们都使用PROJ库。

原始字符串由带有 [ ] 的嵌套参数构成。该方案可以总结如下：

WKT = COMPD_CS[ PROJCS[....] , VERT_CS[...] ]

WKT = "COMPD_CS[\"NAD83(2011) / California zone 2 (ftUS) + NAVD88 height - Geoid12B (ftUS)\",
PROJCS[\"NAD83(2011) / California zone 2 (ftUS)\",GEOGCS[\"NAD83(2011)\",DATUM[\"NAD83_National_Spatial_Reference_System_2011\",SPHEROID[\"GRS 1980\",6378137,298.257222101,AUTHORITY[\"EPSG\",\"7019\"]],AUTHORITY[\"EPSG\",\"1116\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9122\"]],AUTHORITY[\"EPSG\",\"6318\"]],PROJECTION[\"Lambert_Conformal_Conic_2SP\"],PARAMETER[\"standard_parallel_1\",39.83333333333334],PARAMETER[\"standard_parallel_2\",38.33333333333334],PARAMETER[\"latitude_of_origin\",37.66666666666666],PARAMETER[\"central_meridian\",-122],PARAMETER[\"false_easting\",6561666.667],PARAMETER[\"false_northing\",1640416.667],UNIT[\"US survey foot\",0.3048006096012192,AUTHORITY[\"EPSG\",\"9003\"]],AXIS[\"X\",EAST],AXIS[\"Y\",NORTH],AUTHORITY[\"EPSG\",\"6418\"]],
VERT_CS[\"NAVD88 height - Geoid12B (ftUS)\",VERT_DATUM[\"North American Vertical Datum 1988\",2005,AUTHORITY[\"EPSG\",\"5103\"]],UNIT[\"US survey foot\",0.3048006096012192,AUTHORITY[\"EPSG\",\"9003\"]],AUTHORITY[\"EPSG\",\"6360\"]]]"

我想以编程方式获得的是相同的字符串，但在 `VERT_CS.该方案与最初的方案相比是相同的，只是删除了 VERT_CS[...] 部分：

WKT = COMPD_CS[ PROJCS[....] ]

   WKT2 = "COMPD_CS[\"NAD83(2011) / California zone 2 (ftUS) + NAVD88 height - Geoid12B (ftUS)\",
PROJCS[\"NAD83(2011) / California zone 2 (ftUS)\",GEOGCS[\"NAD83(2011)\",DATUM[\"NAD83_National_Spatial_Reference_System_2011\",SPHEROID[\"GRS 1980\",6378137,298.257222101,AUTHORITY[\"EPSG\",\"7019\"]],AUTHORITY[\"EPSG\",\"1116\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9122\"]],AUTHORITY[\"EPSG\",\"6318\"]],PROJECTION[\"Lambert_Conformal_Conic_2SP\"],PARAMETER[\"standard_parallel_1\",39.83333333333334],PARAMETER[\"standard_parallel_2\",38.33333333333334],PARAMETER[\"latitude_of_origin\",37.66666666666666],PARAMETER[\"central_meridian\",-122],PARAMETER[\"false_easting\",6561666.667],PARAMETER[\"false_northing\",1640416.667],UNIT[\"US survey foot\",0.3048006096012192,AUTHORITY[\"EPSG\",\"9003\"]],AXIS[\"X\",EAST],AXIS[\"Y\",NORTH],AUTHORITY[\"EPSG\",\"6418\"]]]"

如何使用 R 以编程方式完成？

【问题讨论】：

标签： r string sp proj

【解决方案1】：

您可以使用gsub 执行此操作，指定一个匹配“VERT_CS”的正则表达式，后跟包含任何字符的方括号。您可以选择将其替换为空的 VERT_CS[] 或完全删除它。

要清空括号内容，您可以这样做：

gsub("VERT_CS\\[.*?\\]+,", "VERT_CS[],", WKT)

要完全删除条目，您可以这样做：

gsub("VERT_CS\\[.*?\\]+,", "", WKT)

使用第二个版本，我们可以看到这完全删除了VERT_CS[...]：

cat(WKT)
COMPD_CS["NAD83(2011) / California zone 2 (ftUS) + NAVD88 height - Geoid12B (ftUS)",
PROJCS["NAD83(2011) / California zone 2 (ftUS)",GEOGCS["NAD83(2011)",DATUM["NAD83_National_Spatial_Reference_System_2011",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","1116"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","6318"]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",39.83333333333334],PARAMETER["standard_parallel_2",38.33333333333334],PARAMETER["latitude_of_origin",37.66666666666666],PARAMETER["central_meridian",-122],PARAMETER["false_easting",6561666.667],PARAMETER["false_northing",1640416.667],UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","6418"]],
VERT_CS["NAVD88 height - Geoid12B (ftUS)",VERT_DATUM["North American Vertical Datum 1988",2005,AUTHORITY["EPSG","5103"]],UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],AUTHORITY["EPSG","6360"]]]

对

COMPD_CS["NAD83(2011) / California zone 2 (ftUS) + NAVD88 height - Geoid12B (ftUS)",
PROJCS["NAD83(2011) / California zone 2 (ftUS)",GEOGCS["NAD83(2011)",DATUM["NAD83_National_Spatial_Reference_System_2011",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","1116"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","6318"]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",39.83333333333334],PARAMETER["standard_parallel_2",38.33333333333334],PARAMETER["latitude_of_origin",37.66666666666666],PARAMETER["central_meridian",-122],PARAMETER["false_easting",6561666.667],PARAMETER["false_northing",1640416.667],UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","6418"]],
UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],AUTHORITY["EPSG","6360"]]]

【讨论】：