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Find element's index in pandas Series
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The cast to value type 'Int32' failed because the materialized value is null
...where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a r...
PHP: Count a stdClass object
...urn the right number when I run the count($obj) function. The object has 30 properties, but the return on the count() function is say 1.
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Declare slice or make slice?
In Go, what is the difference between var s []int and s := make([]int, 0) ?
4 Answers
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Android Hello-World compile error: Intellij cannot find aapt
...set up with an Android development environment using IntelliJ in Ubuntu 12.04. I create an Android Application Module, but when I try to build, I get the following error:
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How to efficiently concatenate strings in go
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880
New Way:
From Go 1.10 there is a strings.Builder type, please take a look at this answer for mo...
Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...seful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred, you can use different values for different kind of errors.
If I'm correct exit codes used to be just positive numbers (I mean in UNIX) and according...
Why in Java 8 split sometimes removes empty strings at start of result array?
... in Java 7 and Java 8. The code is retrieved from grepcode, for version 7u40-b43 and 8-b132.
Java 7
public String[] split(CharSequence input, int limit) {
int index = 0;
boolean matchLimited = limit > 0;
ArrayList<String> matchList = new ArrayList<>();
Matcher m = ma...
How does RegexOptions.Compiled work?
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RegexOptions.Compiled instructs the regular expression engine to compile the regular expression...