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How to plot two histograms together in R?
...gle numeric column which lists the length of all measured carrots (total: 100k carrots) and cucumbers (total: 50k cucumbers).
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Number.sign() in javascript
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More elegant version of fast solution:
var sign = number?number<0?-1:1:0
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Moving decimal places over in a double
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190
If you use double or float, you should use rounding or expect to see some rounding errors. If yo...
Add column with constant value to pandas dataframe [duplicate]
...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 0
7 0
8 ...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
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807
I believe DataFrame.fillna() will do this for you.
Link to Docs for a dataframe and for a Seri...
How do I check to see if a value is an integer in MySQL?
...lar expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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How can I profile Python code line-by-line?
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120
I believe that's what Robert Kern's line_profiler is intended for. From the link:
File: pyston...
How can I repeat a character in Bash?
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410
You can use:
printf '=%.0s' {1..100}
How this works:
Bash expands {1..100} so the command be...
Can I set background image and opacity in the same property?
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Two methods:
Convert to PNG and make the original image 0.2 opacity
(Better method) have a <div> that is position: absolute; before #main and the same height as #main, then apply the background-image and opacity: 0.2; filter: alpha(opacity=20);.
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How to validate an Email in PHP?
...LTER_VALIDATE_EMAIL)
PHP Manual filter_var()
Available in PHP >= 5.2.0
If you don't want to change your code that relied on your function, just do:
function isValidEmail($email){
return filter_var($email, FILTER_VALIDATE_EMAIL) !== false;
}
Note: For other uses (where you need Regex)...