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Pass a data.frame column name to a function
...all foo() like this:
foo(dat,z,x,y)
The problem here is that df$col1 doesn't evaluate the expression col1. It simply looks for a column in df literally called col1. This behavior is described in ?Extract under the section "Recursive (list-like) Objects".
The simplest, and most often recommend...
What is the difference between partitioning and bucketing a table in Hive ?
...ies. Other drawback is having too many partitions is the large number of Hadoop files and directories that are created unnecessarily and overhead to NameNode since it must keep all metadata for the file system in memory.
Bucketing is another technique for decomposing data sets into more manageable p...
Get source JARs from Maven repository
Does anyone have any idea if you can find source JARs on Maven repositories?
19 Answers
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How does Apple find dates, times and addresses in emails?
... languages also. I love this feature and would like to understand how they do it.
6 Answers
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Progress indicator during pandas operations
...for pandas. Unlike the other answers, this will not noticeably slow pandas down -- here's an example for DataFrameGroupBy.progress_apply:
import pandas as pd
import numpy as np
from tqdm import tqdm
# from tqdm.auto import tqdm # for notebooks
df = pd.DataFrame(np.random.randint(0, int(1e8), (1000...
How to “warm-up” Entity Framework? When does it get “cold”?
...ion. Especially, for those queries that take very long to compile and that don't change. That way you move the performance overhead from runtime to compile time. Also this won't introduce any lag. But of course this change goes through to the database, so it's not so easy to deal with. Code is more ...
Search All Fields In All Tables For A Specific Value (Oracle)
.../22/2008P09RR8' is a value selected directly from a single column? If you don't know at all where it is coming from, it could be a concatenation of several columns, or the result of some function, or a value sitting in a nested table object. So you might be on a wild goose chase trying to check ev...
smart pointers (boost) explained
What is the difference between the following set of pointers? When do you use each pointer in production code, if at all?
4...
How to use 'find' to search for files created on a specific date? [closed]
How do I use the UNIX command find to search for files created on a specific date?
9 Answers
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Most efficient way to convert an HTMLCollection to an Array
...ion);
But note per @JussiR's comment, that unlike the "verbose" form, it does create an empty, unused, and indeed unusable array instance in the process. What compilers do about this is outside the programmer's ken.
Edit
Since ECMAScript 2015 (ES 6) there is also Array.from:
var arr = Array.fr...