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Generate random numbers with a given (numerical) distribution
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13 Answers
13
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Add column with constant value to pandas dataframe [duplicate]
...8]: from numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = df.a[:5]
In [12]: dfa, sa = df.align(s, axis=0)
In [13]: dfa
Out[13]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 ...
Filter rows which contain a certain string
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263
The answer to the question was already posted by the @latemail in the comments above. You can us...
What is the difference between Ruby 1.8 and Ruby 1.9
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Array.to_s Now Contains Punctuation
Ruby 1.9
irb(main):001:0> [1,2,3].to_s
=> "[1, 2, 3]"
Ruby 1.8.6
irb(main):001:0> [1,2,3].to_s
=> "123"
Action: Use .join instead
Colon No Longer Valid In When Statements
Ruby 1.9
irb(main):001:0> case 'a'; when /\w/: puts 'word'; end...
Python and pip, list all versions of a package that's available?
...h 2020, many people have reported that yolk, installed via pip install yolk3k, only returns latest version. Chris's answer seems to have the most upvotes and worked for me)
The script at pastebin does work. However it's not very convenient if you're working with multiple environments/hosts because...
Swapping column values in MySQL
...t. This method doesn't swap the values if one of them is NULL. Use method #3 that doesn't have this limitation.
UPDATE swap_test SET x=y, y=@temp WHERE (@temp:=x) IS NOT NULL;
This method was offered by Dipin in, yet again, the comments of http://beerpla.net/2009/02/17/swapping-column-values-in-mys...
Remove empty elements from an array in Javascript
... to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
return el != null;
});
console.log(filtered);
It will depend on what you consider to be "empty" for example, if you were d...
Convert list of dictionaries to a pandas DataFrame
...24
cs95
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answered Dec 17 '13 at 15:35
jorisjoris
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Find integer index of rows with NaN in pandas dataframe
...n use to index back into df, e.g.:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values.tolist()
[df_index.index(i) for i in index]
>>> [3, 6]
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Why is address zero used for the null pointer?
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edited May 3 '10 at 17:44
answered May 3 '10 at 17:22
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