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What's the best practice to round a float to 2 decimals? [duplicate]
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160
I was working with statistics in Java 2 years ago and I still got the codes of a function that a...
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...
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...
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 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 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 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...
Tricky Google interview question
... implementation of Dijkstra’s solution.
int main()
{
const int n = 20; // Generate the first n numbers
std::vector<int> v(n);
v[0] = 1;
int i2 = 0; // Index for 2
int i5 = 0; // Index for 5
int x2 = 2 * v[i2]; // Next two candidat...