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Difference between Big-O and Little-O Notation
... O(g) says, essentially
For at least one choice of a constant k > 0, you can find a constant a such that the inequality 0 <= f(x) <= k g(x) holds for all x > a.
Note that O(g) is the set of all functions for which this condition holds.
f ∈ o(g) says, essentially
For every c...
dplyr: “Error in n(): function should not be called directly”
...
120
I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not a ...
How to put individual tags for a scatter plot
...se plt.annotate:
import numpy as np
import matplotlib.pyplot as plt
N = 10
data = np.random.random((N, 4))
labels = ['point{0}'.format(i) for i in range(N)]
plt.subplots_adjust(bottom = 0.1)
plt.scatter(
data[:, 0], data[:, 1], marker='o', c=data[:, 2], s=data[:, 3] * 1500,
cmap=plt.get_c...
Get local IP address in node.js
... net of nets[name]) {
// skip over non-ipv4 and internal (i.e. 127.0.0.1) addresses
if (net.family === 'IPv4' && !net.internal) {
if (!results[name]) {
results[name] = [];
}
results[name].push(net.address);
}
}
...
Efficient way to determine number of digits in an integer
...
107
Well, the most efficient way, presuming you know the size of the integer, would be a lookup. S...
How to get the separate digits of an int number?
I have numbers like 1100, 1002, 1022 etc. I would like to have the individual digits, for example for the first number 1100 I want to have 1, 1, 0, 0.
...
Parse (split) a string in C++ using string delimiter (standard C++)
...>=tiger";
std::string delimiter = ">=";
std::string token = s.substr(0, s.find(delimiter)); // token is "scott"
The find(const string& str, size_t pos = 0) function returns the position of the first occurrence of str in the string, or npos if the string is not found.
The substr(size_t p...
AWK: Access captured group from line pattern
...
answered Jun 2 '10 at 12:50
Peter TillemansPeter Tillemans
33k99 gold badges7272 silver badges109109 bronze badges
...
Replace values in list using Python [duplicate]
...
207
Build a new list with a list comprehension:
new_items = [x if x % 2 else None for x in items]
...
Is there a standard sign function (signum, sgn) in C/C++?
...+ version yet:
template <typename T> int sgn(T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or...