Question

我想用相同长度的字符串向量的相应元素替换逻辑向量中的TRUE的任何实例。

例如，我想结合一下：

my_logical <- c(TRUE, FALSE, TRUE)
my_string <- c("A", "B", "C")

产生：

c("A", "", "C")

我知道：

my_string[my_logical]

给予：

"A" "C"

，但似乎无法弄清楚如何返回相同长度的向量。我的第一个想法是将向量简单地相乘，但这会引起错误“二进制运算符的非数字参数”。

Answer 1

带有replace

的另一个选项

replace(my_string, !my_logical, "")
#[1] "A" ""  "C"

Answer 2

那又怎么样：

my_logical <- c(TRUE, FALSE, TRUE)
my_string <- c("A", "B", "C")
my_replace <- ifelse(my_logical==TRUE,my_string,'')
my_replace
[1] "A" ""  "C"

编辑，谢谢@www：

ifelse(my_logical, my_string, "")

Answer 3

当ifelse等于NA时使用my_logical添加FALSE（否则为TRUE）。使用此子集。

new <- my_string[ifelse(!my_logical, NA, T)]
new

[1] "A" NA  "C"

如果您想让""超过NA，请继续执行此操作。

new[is.na(new)] <- ""

[1] "A" ""  "C"

Answer 4

也许：

<property>
  <name>plugin.includes</name>
  <value>protocol-(selenium|http)|urlfilter-(regex|validator)|parse-(html|tika)|index-(basic|anchor)|indexer-solr|scoring-opic|urlnormalizer-(pass|regex|basic)</value>
  <description>Regular expression naming plugin directory names to
  include.  Any plugin not matching this expression is excluded.
  In any case you need at least include the nutch-extensionpoints plugin. By
  default Nutch includes crawling just HTML and plain text via HTTP,
  and basic indexing and search plugins. In order to use HTTPS please enable 
  protocol-httpclient, but be aware of possible intermittent problems with the 
  underlying commons-httpclient library. Set parsefilter-naivebayes for classification based focused crawler.
  </description>
</property>
<property>
  <name>selenium.driver</name>
  <value>firefox</value>
  <description>
    A String value representing the flavour of Selenium 
    WebDriver() to use. Currently the following options
    exist - 'firefox', 'chrome', 'safari', 'opera', 'phantomjs' and 'remote'.
    If 'remote' is used it is essential to also set correct properties for
    'selenium.hub.port', 'selenium.hub.path', 'selenium.hub.host',
    'selenium.hub.protocol', 'selenium.grid.driver' and 'selenium.grid.binary'.
  </description>
</property>

当然，这会覆盖现有对象。

如何将字符串向量应用于逻辑向量

4 个答案: