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How to read a file without newlines?
...ead().splitlines()
Or you can strip the newline by hand:
temp = [line[:-1] for line in file]
Note: this last solution only works if the file ends with a newline, otherwise the last line will lose a character.
This assumption is true in most cases (especially for files created by text editors, ...
Factors in R: more than an annoyance?
... same. However, you end up with warnings in your code:
lm(Petal.Length ~ -1 + Species, data=iris)
# Call:
# lm(formula = Petal.Length ~ -1 + Species, data = iris)
# Coefficients:
# Speciessetosa Speciesversicolor Speciesvirginica
# 1.462 4.260 5.552 ...
How to control the line spacing in UILabel
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edited Jan 5 '18 at 8:31
Bart van Kuik
3,8212626 silver badges4444 bronze badges
answered Ap...
What is the difference between quiet NaN and signaling NaN?
...FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and provides standardized ways to create and test for NaNs. However, whether the controls are implemented is not well standardized and floating-point except...
How to get next/previous record in MySQL?
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edited Jul 10 '12 at 10:53
Vimalnath
6,12222 gold badges2323 silver badges4444 bronze badges
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How are multi-dimensional arrays formatted in memory?
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147
A static two-dimensional array looks like an array of arrays - it's just laid out contiguously...
PreparedStatement IN clause alternatives?
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195
An analysis of the various options available, and the pros and cons of each is available here....
Javascript shorthand ternary operator
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179
var startingNumber = startingNumber || 1;
Something like that what you're looking for, where...
How to track down a “double free or corruption” error
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answered May 25 '10 at 8:42
HasturkunHasturkun
31.2k55 gold badges6565 silver badges9595 bronze badges
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...