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Cleaning `Inf` values from an R dataframe
...ption 1
Use the fact that a data.frame is a list of columns, then use do.call to recreate a data.frame.
do.call(data.frame,lapply(DT, function(x) replace(x, is.infinite(x),NA)))
Option 2 -- data.table
You could use data.table and set. This avoids some internal copying.
DT <- data.table(dat)...
Efficient method to generate UUID String in JAVA (UUID.randomUUID().toString() without the dashes)
...y. There's an API I'm working with (high profile, well known) that doesn't allow dashes in its UUID. You have to strip them.
– Michael Gaines
Oct 28 '15 at 3:28
20
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Can promises have multiple arguments to onFulfilled?
I'm following the spec here and I'm not sure whether it allows onFulfilled to be called with multiple arguments. For example:
...
How to fix “Referenced assembly does not have a strong name” error?
...
To avoid this error you could either:
Load the assembly dynamically, or
Sign the third-party assembly.
You will find instructions on signing third-party assemblies in .NET-fu: Signing an Unsigned Assembly (Without Delay Signing).
Signing Third-Party Assemblies
The basic principle t...
Using str_replace so that it only acts on the first match?
...
There's no version of it, but the solution isn't hacky at all.
$pos = strpos($haystack, $needle);
if ($pos !== false) {
$newstring = substr_replace($haystack, $replace, $pos, strlen($needle));
}
Pretty easy, and saves the performance penalty of regular expressions.
Bonus: If...
NoSQL - MongoDB vs CouchDB [closed]
...~2.5Gb
Text search integrated
GridFS to store big data + metadata (not actually an FS)
Data center aware
Best used: If you need dynamic queries. If you prefer to define indexes, not map/reduce functions. If you need good performance on a big DB. If you wanted CouchDB, but your data changes too muc...
Convert pandas dataframe to NumPy array
...p.nan)
# array([ 1., 2., nan])
This is called out in the docs.
If you need the dtypes...
As shown in another answer, DataFrame.to_records is a good way to do this.
df.to_records()
# rec.array([('a', -1, 4), ('b', 2, 5), ('c', 3, 6)],
# dtype=[('index',...
All possible array initialization syntaxes
What are all the array initialization syntaxes that are possible with C#?
16 Answers
1...
Extracting specific columns from a data frame
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Using the dplyr package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
share
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Pandas conditional creation of a series/dataframe column
...
List comprehension is another way to create another column conditionally. If you are working with object dtypes in columns, like in your example, list comprehensions typically outperform most other methods.
Example list comprehension:
df['color'] = ['red' if x == 'Z' else 'green' for x in d...