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How to detect a Christmas Tree? [closed]
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Simple regular expression for a decimal with a precision of 2
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408
Valid regex tokens vary by implementation. A generic form is:
[0-9]+(\.[0-9][0-9]?)?
More co...
Add a common Legend for combined ggplots
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108
Update 2015-Feb
See Steven's answer below
df1 <- read.table(text="group x y
gro...
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 slice an array in Bash
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answered Aug 26 '09 at 17:10
Paused until further notice.Paused until further notice.
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Applying a function to every row of a table using dplyr?
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202
As of dplyr 0.2 (I think) rowwise() is implemented, so the answer to this problem becomes:
iri...
How do you detect Credit card type based on number?
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+50
The credit/debit card number is referred to as a PAN, or Primary Account Number. The first six digits of the PAN are taken from the I...
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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Shortest distance between a point and a line segment
...at l2 = length_squared(v, w); // i.e. |w-v|^2 - avoid a sqrt
if (l2 == 0.0) return distance(p, v); // v == w case
// Consider the line extending the segment, parameterized as v + t (w - v).
// We find projection of point p onto the line.
// It falls where t = [(p-v) . (w-v)] / |w-v|^2
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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...