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When to use Hadoop, HBase, Hive and Pig?
...n to my answer. No self promotion intended)
Both Hive and Pig queries get converted into MapReduce jobs under the hood.
HTH
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Is there a difference between foreach and map?
...eturns another list of the same size with the transformed members (such as converting a list of strings to uppercase)
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Mean per group in a data.frame [duplicate]
...0.33333
#3 Cat 2 44.66667 54.00000
Using data.table:
# At first, I convert the data.frame to data.table and then I group it
setDT(d)
d[, .(Rate1 = mean(Rate1), Rate2 = mean(Rate2)), by = .(Name)]
# Name Rate1 Rate2
#1: Aira 16.33333 47.00000
#2: Ben 31.33333 50.33333
#3: Cat 44.66...
How to iterate over arguments in a Bash script
I have a complex command that I'd like to make a shell/bash script of. I can write it in terms of $1 easily:
8 Answers
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How to prevent buttons from submitting forms
...be used PHP sessions and neither cookies are allowed!
So any link must be converted to such form submit, so the login data is not lost.
When no login is yet done, it must also work. So no validation must be performed on links.
But I want to present a message to the user if the user has not entered ...
Creating temporary files in bash
...standard, but it does exist on many platforms. The "X"s will generally get converted into some randomness, and more will probably be more random; however, some systems (busybox ash, for one) limit this randomness more significantly than others
By the way, safe creation of temporary files is impor...
Does a const reference class member prolong the life of a temporary?
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Only local const references prolong the lifespan.
The standard specifies such behavior in §8.5.3/5, [dcl.init.ref], the section on initializers of reference declarations. The reference in your example is bound to the constructor's argument n, and becomes invalid when the object n...
Why am I seeing “TypeError: string indices must be integers”?
... to get github issues into a readable form. Using the advice on How can I convert JSON to CSV? I came up with this:
6 Ans...
add a string prefix to each value in a string column using Pandas
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If you load you table file with dtype=str
or convert column type to string df['a'] = df['a'].astype(str)
then you can use such approach:
df['a']= 'col' + df['a'].str[:]
This approach allows prepend, append, and subset string of df.
Works on Pandas v0.23.4, v0.24.1. ...
Can a JSON value contain a multiline string
...on tool. Link . It allows you to write text multi-lined in editor and then converts it to the proper valid JSON format. Note: it adds '\n' characters for the new lines, but you can simply delete them in any text editor with the "Replace all.." function.
P.S. Should be a comment to the question, bu...