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Python Infinity - Any caveats?
...-a-number (NaN) values from simple arithmetic involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**...
Java: parse int value from a char
...
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edited Apr 30 '18 at 4:24
Neuron
3,54333 gold badges2323 silver badges4040 bronze badges
a...
C++ performance challenge: integer to std::string conversion
...
#include <string>
const char digit_pairs[201] = {
"00010203040506070809"
"10111213141516171819"
"20212223242526272829"
"30313233343536373839"
"40414243444546474849"
"50515253545556575859"
"60616263646566676869"
"70717273747576777879"
"80818283848586...
Algorithm for Determining Tic Tac Toe Game Over
...;
//check end conditions
//check col
for(int i = 0; i < n; i++){
if(board[x][i] != s)
break;
if(i == n-1){
//report win for s
}
}
//check row
for(int i = 0; i < n; i++){
...
How does this CSS produce a circle?
...
How does a border of 180 pixels with height/width-> 0px become a circle with a radius of 180 pixels?
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source...
Get last n lines of a file, similar to tail
... till it's found the right number of '\n' characters.
def tail( f, lines=20 ):
total_lines_wanted = lines
BLOCK_SIZE = 1024
f.seek(0, 2)
block_end_byte = f.tell()
lines_to_go = total_lines_wanted
block_number = -1
blocks = [] # blocks of size BLOCK_SIZE, in reverse orde...
Converting a column within pandas dataframe from int to string
...
In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [18]: df.dtypes
Out[18]:
A int64
B int64
dtype: object
Convert a series
In [19]: df['A'].apply(str)
Ou...
Numpy - add row to array
...pare its row to a number: i < 3?
EDIT after OP's comment:
A = array([[0, 1, 2], [0, 2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
...
Minimizing NExpectation for a custom distribution in Mathematica
...f we plot pdf2 it looks exactly as your Plot
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x], {x, 0, .3}]
Now to the expected value. If I understand it correctly we have to integrate x * pdf[x] from -inf to +inf for a normal expected value.
x * pdf[x] looks like
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x]*x...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>&gt...