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Split delimited strings in a column and insert as new rows [duplicate]
...is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length))...
Case-INsensitive Dictionary with string key-type in C#
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328
This seemed related, but I didn't understand it properly: c# Dictionary: making the Key case...
Regex match one of two words
I have an input that can have only 2 values apple or banana . What regular expression can I use to ensure that either of the two words was submitted?
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Mongodb Explain for Aggregation framework
...ve you the desired results (documentation here).
For older versions >= 2.6, you will need to use the explain option for aggregation pipeline operations
explain:true
db.collection.aggregate([
{ $project : { "Tags._id" : 1 }},
{ $unwind : "$Tags" },
{ $match: {$or: [{"Tags._id":"tag1...
Ruby on Rails: How do you add add zeros in front of a number if it's under 10?
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142
Did you mean sprintf '%02d', n?
irb(main):003:0> sprintf '%02d', 1
=> "01"
irb(main):004:...
Library not loaded: /usr/local/opt/readline/lib/libreadline.6.2.dylib
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22 Answers
22
Active
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Java String split removed empty values
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Jan 30 '13 at 10:44
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How to hide command output in Bash
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250
Use this.
{
/your/first/command
/your/second/command
} &> /dev/null
Explanation
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Keep only first n characters in a string?
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edited Apr 12 '14 at 11:37
andrewb
4,80266 gold badges3030 silver badges5151 bronze badges
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Which data type for latitude and longitude?
...pe point - combines (x,y) which can be your lat / long. Occupies 16 bytes: 2 float8 numbers internally.
Or make it two columns of type float (= float8 or double precision). 8 bytes each.
Or real (= float4) if additional precision is not needed. 4 bytes each.
Or even numeric if you need absolute pre...