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Moving decimal places over in a double
...
190
If you use double or float, you should use rounding or expect to see some rounding errors. If yo...
Split (explode) pandas dataframe string entry to separate rows
... for _, row in a.iterrows()]).reset_index()
Out[55]:
index 0
0 a 1
1 b 1
2 c 1
3 d 2
4 e 2
5 f 2
Then you just have to rename the columns
share
|
impr...
Gray out image with CSS?
...age" src="something.jpg" />
</div>
css:
#myImage {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
}
/* or */
#wrapper {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
background-color: #000;
}
...
Converting strings to floats in a DataFrame
...) or pd.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will fail; its also series by series
so it won't convert say a complete string column
In [10]: df = DataFrame(dict(A = Series(['1.0','1']), B = Series...
Django Server Error: port is already in use
...
A more simple solution just type sudo fuser -k 8000/tcp.
This should kill all the processes associated with port 8000.
EDIT:
For osx users you can use sudo lsof -t -i tcp:8000 | xargs kill -9
sha...
What does axis in pandas mean?
...
It specifies the axis along which the means are computed. By default axis=0. This is consistent with the numpy.mean usage when axis is specified explicitly (in numpy.mean, axis==None by default, which computes the mean value over the flattened array) , in which axis=0 along the rows (namely, index ...
What is the best way to compute trending topics or tags?
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104
This problem calls for a z-score or standard score, which will take into account the historical...
Change Active Menu Item on Page Scroll?
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207
It's done by binding to the scroll event of the container (usually window).
Quick example:
//...
Is there a performance gain in using single quotes vs double quotes in ruby?
...
$ ruby -v
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.0.0]
$ cat benchmark_quotes.rb
# As of Ruby 1.9 Benchmark must be required
require 'benchmark'
n = 1000000
Benchmark.bm(15) do |x|
x.report("assign single") { n.times do; c =...
Why is a round-trip conversion via a string not safe for a double?
...mber->precision = precision;
if (((FPDOUBLE*)&value)->exp == 0x7FF) {
number->scale = (((FPDOUBLE*)&value)->mantLo || ((FPDOUBLE*)&value)->mantHi) ? SCALE_NAN: SCALE_INF;
number->sign = ((FPDOUBLE*)&value)->sign;
number->digits[0] =...