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How do I replace NA values with zeros in an R dataframe?
...eplace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10 NA 2 1 7 2
3 1 1 6 3 6 NA 1 4 1 6
4 NA 4 NA 7 10 2 NA 4 1 8
5 1 2 4 NA 2 6 2 6 7 4
6 NA 3 NA NA 10 2 1 10 8 4
7 4 4 9 ...
Python list iterator behavior and next(iterator)
...t;>> for i in a:
... print(i)
... next(a)
...
0
1
2
3
4
5
6
7
8
9
So 0 is the output of print(i), 1 the return value from next(), echoed by the interactive interpreter, etc. There are just 5 iterations, each iteration resulting in 2 lines being written to the terminal.
If you assign ...
How to change the default collation of a table?
...rt to clause):
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci;
Edited the answer, thanks to the prompting of some comments:
Should avoid recommending utf8. It's almost never what you want, and often leads to unexpected messes. The utf8 character set...
Re-ordering columns in pandas dataframe based on column name [duplicate]
...
|
edited Dec 18 '18 at 22:57
gcamargo
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...
How to randomly sort (scramble) an array in Ruby?
...
Tim Cooper
138k3434 gold badges286286 silver badges249249 bronze badges
answered Nov 29 '09 at 18:49
Ron GejmanRon...
Maven is not working in Java 8 when Javadoc tags are incomplete
...e code) then you can disable this check.
DocLint is a new feature in Java 8, which is summarized as:
Provide a means to detect errors in Javadoc comments early in the
development cycle and in a way that is easily linked back to the
source code.
This is enabled by default, and will run a w...
Syntax behind sorted(key=lambda: …)
...aurang Tandon
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answered Jan 23 '12 at 2:26
EvanEvan
5,59111 gold badge2121 ...
Unique (non-repeating) random numbers in O(1)?
...s off at 10:
+--+--+--+--+--+--+--+--+--+--+--+
| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9|10|
+--+--+--+--+--+--+--+--+--+--+--+
^
max
At each iteration, a random number r is selected between 0 and max, array[r] and array[max] are swapped, t...
How to find the installed pandas version
... [76]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]: pd.show_versions(as_json=False)
INSTALLED VERSIONS
------------------
commit: None
pytho...
Java 8 Stream and operation on arrays
I have just discovered the new Java 8 stream capabilities. Coming from Python, I was wondering if there was now a neat way to do operations on arrays like summing, multiplying two arrays in a "one line pythonic" way ?
...