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Best practice to validate null and empty collection in Java
...return ((Map) obj).isEmpty();
}
// else
return false;
}
for String best is:
boolean isNullOrEmpty = (str==null || str.trim().isEmpty());
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Using capistrano to deploy from different git branches
...S, orelse the argument would not pass through to cap, when using fetch(:var_name, 'default') to get it.
– Frederik Struck-Schøning
Jan 23 '14 at 10:14
1
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Does using final for variables in Java improve garbage collection?
...e improvement. This is used when you have a number of public static final Strings in a class.
In general, the compiler and runtime will optimize where it can. It is best to write the code appropriately and not try to be too tricky. Use final when you do not want the variable to be modified. Ass...
Passing command line arguments to R CMD BATCH
...CH -blabla my_script.R
commandArgs() will receive -blabla as a character string in this case. See the help for details:
$ R CMD BATCH --help
Usage: R CMD BATCH [options] infile [outfile]
Run R non-interactively with input from infile and place output (stdout
and stderr) to another file. If not ...
How accurately should I store latitude and longitude?
...will get the same desirable round trip consistency guarantees you get with String values. This website is great for helping you play with a Geohash.
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JavaScript: Object Rename Key
... convert an API response that was prefixing Country Names with unnecessary string. Turned Object into array of keys and mapped through each key with substring method and returned a new object with new key and value indexed by original key
– Akin Hwan
Feb 10 '18...
How to compare two floating point numbers in Bash?
...are compared as numbers and fractional parts are intentionally compared as strings. Variables are split into integer and fractional parts using this method.
Won't compare floats with integers (without dot).
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Relative frequencies / proportions with dplyr
...
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vigne...
What GRANT USAGE ON SCHEMA exactly do?
... webapp
# * you have to change '$ROLE_LOCAL', '$ROLE_REMOTE' and '$DB'
# strings with your desired names
# * it's preferable that $ROLE_LOCAL == $DB
#-------------------------------------------------------------------------------
//----------- SKIP THIS PART UNTIL POSTGRES JDBC ADDS SCRAM - STAR...
How does the Google “Did you mean?” Algorithm work?
...arches that have the shortest Levenshtein distance from the entered search string, then pick the one with the most results.
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