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How can I represent an infinite number in Python?
...t infinity is defined in the norm IEEE 754-1985 (en.wikipedia.org/wiki/IEEE_754-1985), which Any modern language will rely on. Another point is that, according to this norm, infinity must (obviously) be a floating-point number. This might explain why Python have chosen this akward syntax.
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How can I remove all objects but one from the workspace in R?
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require(gdata)
keep(object_1,...,object_n,sure=TRUE)
ls()
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Is PowerShell ready to replace my Cygwin shell on Windows? [closed]
...would be: sed 's/pattern/replacement/' file, which is roughly gc file | %{$_ -replace 'pattern','replacement'}, and similarly for awk: awk 'BEGIN {} /pat1/ {action1} /pat2/ {action2} END {}' file is roughly {BEGIN {}; switch -r -c -file file { 'pat1' {action1} 'pat2' {action2}}; END{};}
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Eclipse/Java code completion not working
... triggers for Java:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._
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Using Git with Visual Studio [closed]
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I usually add .user, *.suo, bin, obj, . and _* to my ignore list... if there's one of the above I want added, I can still add it manually.
– Tracker1
Mar 30 '11 at 0:17
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Difference between local and global indexes in DynamoDB
...s from the index, not from the base table.
– ethanxyz_0
Aug 8 '17 at 2:00
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@bsd It would make se...
Change the font of a UIBarButtonItem
...Don't forget the exclamation mark (!) after the font. The error message: "'_' is not convertible to 'String'" is not really helpful.
– Ciryon
Sep 3 '15 at 6:41
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Determine the number of NA values in a column
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If you are looking for NA counts for each column in a dataframe then:
na_count <-sapply(x, function(y) sum(length(which(is.na(y)))))
should give you a list with the counts for each column.
na_count <- data.frame(na_count)
Should output the data nicely in a dataframe like:
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How does Java handle integer underflows and overflows and how would you check for it?
...int left, int right) {
if (right < 0 && right != Integer.MIN_VALUE) {
return willSubtractionOverflow(left, -right);
} else {
return (~(left ^ right) & (left ^ (left + right))) < 0;
}
}
public static boolean willSubtractionOverflow(int left, int right) {...
UnmodifiableMap (Java Collections) vs ImmutableMap (Google) [duplicate]
... edited Sep 24 '19 at 7:25
sP_
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answered Mar 25 '14 at 13:52
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