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Relative frequencies / proportions with dplyr
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295
Try this:
mtcars %>%
group_by(am, gear) %>%
summarise(n = n()) %>%
mutate(freq =...
How to access maven.build.timestamp for resource filtering
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edited Sep 12 at 15:02
Java Crazy
5777 bronze badges
answered Nov 5 '12 at 9:04
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Comparing mongoose _id and strings
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375
Mongoose uses the mongodb-native driver, which uses the custom ObjectID type. You can compare Ob...
Check if a Postgres JSON array contains a string
...rom rabbits where (info->'food')::jsonb ? 'carrots';
Execution time: 1255.501 ms
d=# alter table rabbits alter info type jsonb using info::jsonb;
d=# explain analyze select info->'name' from rabbits where info->'food' ? 'carrots';
Execution time: 465.919 ms
d=# create index on rabbits u...
What is the difference between .text, .value, and .value2?
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edited Sep 8 '15 at 11:01
answered Jun 28 '13 at 11:17
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Why do results vary based on curly brace placement?
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edited Jan 29 at 11:25
Edric
15.5k99 gold badges5656 silver badges7171 bronze badges
answered Sep 4...
What is meant by Ems? (Android TextView)
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395
android:ems or setEms(n) sets the width of a TextView to fit a text of n 'M' letters regardless ...
create two method for same url pattern with different arguments
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answered Apr 6 '13 at 16:25
krygerkryger
11.2k77 gold badges4040 silver badges5959 bronze badges
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C#/Linq: Apply a mapping function to each element in an IEnumerable?
...od:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
IEnumerable<string> strings = integers.Select(i => i.ToString());
Or in LINQ syntax:
IEnumerable<int> integers = new List<int>() { 1, 2, 3, 4, 5 };
var strings = from i in integers
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Microsecond timing in JavaScript
...be much smaller than Date).
now() is supported in Chrome stable, Firefox 15+, and IE10. There are also several polyfills available.
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