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Delete all but the most recent X files in bash
Is there a simple way, in a pretty standard UNIX environment with bash, to run a command to delete all but the most recent X files from a directory?
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Java: how do I get a class literal from a generic type?
... String.class denotes the Class
object that represents the type
String and is identical to the
Class object that is returned when
method getClass is invoked on a
String object. A class literal can
be used for runtime type checks and
for reflection.
Parameterized types lose their ...
How to convert CSV file to multiline JSON?
...t yourself. So we just need to pull the loop out of the call to json.dump and interpose newlines for each document written.
import csv
import json
csvfile = open('file.csv', 'r')
jsonfile = open('file.json', 'w')
fieldnames = ("FirstName","LastName","IDNumber","Message")
reader = csv.DictReader(...
How do I copy a version of a single file from one git branch to another?
...ng the commit hash you can pull files from any commit
This works for files and directories
overwrites the file myfile.txt and mydir
Wildcards don't work, but relative paths do
Multiple paths can be specified
an alternative:
git show commit_id:path/to/file > path/to/file
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How can I specify a local gem in my Gemfile?
...ts under version control. It lets you keep checking in both projects - gem and project using the gem - such that others can don't have to check out the gem source or share the same paths.
– mahemoff
Jun 12 '14 at 8:42
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How to make graphics with transparent background in R using ggplot2?
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Updated with the theme() function, ggsave() and the code for the legend background:
df <- data.frame(y = d, x = 1, group = rep(c("gr1", "gr2"), 50))
p <- ggplot(df) +
stat_boxplot(aes(x = x, y = y, color = group),
fill = "transparent" # for the...
Convert column classes in data.table
... dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.charac...
Isn't “package private” member access synonymous with the default (no-modifier) access?
...ion uses, along with the usage of "default access." Aren't package-private and default access both synonymous with protected?
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How to break out of nested loops?
If I use a break statement, it will only break inner loop and I need to use some flag to break the outer loop. But if there are many nested loops, the code will not look good.
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What does Maven Update Project do in Eclipse?
...ava version, you will find that Eclipse will ask you to update the project and afterwards the configured Java runtime in the project will have changed to reflect what your Maven pom indicates.
That is an important thing to keep in mind: the Maven pom is the lead in this kind of project setup. If yo...