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How do I replace NA values with zeros in an R dataframe?
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The dplyr hybridized options are now around 30% faster than the Base R subset reassigns. On a 100M datapoint dataframe mutate_all(~replace(., is.na(.), 0)) runs a half a second faster than the base R d[is.na(d)] <- 0 option. What one wants to avoid specifically is using an ifelse() or ...
What text editor is available in Heroku bash shell? [closed]
I'm trying to update httpd.conf in my Cedar-based Heroku app. I got to my Heroku bash with
15 Answers
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Generate class from database table
... WHEN 'bigint' THEN CASE C.IS_NULLABLE
WHEN 'YES' THEN 'Int64?'
ELSE 'Int64'
END
WHEN 'binary' THEN 'Byte[]'
WHEN 'bit' THEN CASE C.IS_NULLABLE
WHEN 'YES' THEN 'bool?'
ELSE 'bool'
END
WHEN 'char' THEN 'st...
Legality of COW std::string implementation in C++11
... Dave SDave S
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4
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What is the fastest substring search algorithm?
...ute force may win.
Edit:
A different algorithm might be best for finding base pairs, english phrases, or single words. If there were one best algorithm for all inputs, it would have been publicized.
Think about the following little table. Each question mark might have a different best search al...
What does “%.*s” mean in printf?
...ll terminator, for example a string which is input from any stream or file based source. Which is far more often the use case I have encountered, than merely print prettines.
– Conrad B
Oct 24 '18 at 8:04
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Share Large, Read-Only Numpy Array Between Multiprocessing Processes
...variable.
From the discussion page you linked, it appears that support for 64-bit Linux was added to sharedmem a while back, so it could be a non-issue.
I don't know about this one.
No. Refer to example below.
Example
#!/usr/bin/env python
from multiprocessing import Process
import sharedmem
impo...
How can I remove the first line of a text file using bash/sed script?
...n't try to delete the first line but maintains a persistent (probably file-based) offset into the file A so that, next time it runs, it could seek to that offset, process the line there, and update the offset.
Then, at a quiet time (midnight?), it could do special processing of file A to delete all...
Best way to store date/time in mongodb
...goDB shell version: 2.4.9
connecting to: 10.0.1.223/test
Create your database by inserting items
> db.penguins.insert({"penguin": "skipper"})
> db.penguins.insert({"penguin": "kowalski"})
>
Lets make that database the one we are on now
> use penguins
switched to db penguins
Get ...
How to convert a byte array to a hex string in Java?
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A Guava solution, for completeness:
import com.google.common.io.BaseEncoding;
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byte[] bytes = "Hello world".getBytes(StandardCharsets.UTF_8);
final String hex = BaseEncoding.base16().lowerCase().encode(bytes);
Now hex is "48656c6c6f20776f726c64".
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