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What is causing this ActiveRecord::ReadOnlyRecord error?
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283
Rails 2.3.3 and lower
From the ActiveRecord CHANGELOG(v1.12.0, October 16th, 2005):
Introdu...
Assigning a variable NaN in python without numpy
...>>> import math
>>> math.isnan(nan)
True
Before Python 3.5, one could use float("nan") (case insensitive).
Note that checking to see if two things that are NaN are equal to one another will always return false. This is in part because two things that are "not a number" cannot (s...
Alternate background colors for list items
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293
How about some lovely CSS3?
li { background: green; }
li:nth-child(odd) { background: red; }
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What are the advantages of Sublime Text over Notepad++ and vice-versa? [closed]
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3 Answers
3
Active
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How can I add the sqlite3 module to Python?
Can someone tell me how to install the sqlite3 module alongside the most recent version of Python?
I am using a Macbook, and on the command line, I tried:
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How can I iterate over files in a given directory?
...(directory, filename))
continue
else:
continue
Python 3.6 version of the above answer, using os - assuming that you have the directory path as a str object in a variable called directory_in_str:
import os
directory = os.fsencode(directory_in_str)
for file in os.listdir(dir...
emacs/elisp: What is the hash (pound, number sign, octothorp) symbol used for?
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3 Answers
3
Active
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Find XOR of all numbers in a given range
...s table for 4-bit numbers:
0000 <- 0 [a]
0001 <- 1 [1]
0010 <- 3 [a+1]
0011 <- 0 [0]
0100 <- 4 [a]
0101 <- 1 [1]
0110 <- 7 [a+1]
0111 <- 0 [0]
1000 <- 8 [a]
1001 <- 1 [1]
1010 <- 11 [a+1]
1011 <- 0 [0]
1100 <- 12 [a]
1101 <- 1 [1]
1110 <- 15 ...
Is there a way to change the spacing between legend items in ggplot2?
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ggplot2 v3.0.0 released in July 2018 has working options to modify legend.spacing.x, legend.spacing.y and legend.text.
Example: Increase horizontal spacing between legend keys
library(ggplot2)
ggplot(mtcars, aes(factor(cyl), fil...
node and Error: EMFILE, too many open files
...PE DEVICE SIZE/OFF NODE NAME
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nodejs 12211 root 1012u IPv4 151317015 0t0 TCP 10.101.42.209:40371->54.236.3.170:80 (ESTABLISHED)
nodejs 12211 root 1013u IPv4 151279902 0t0 TCP 10.101.42.209:43656->54.236.3.172:80 (ESTABLISHED)
nodejs 12211 root 1014u IPv4 ...