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Ruby on Rails: how to render a string as HTML?
...;
OR
@str = "<b>Hi</b>"
<%= @str.html_safe %>
Using raw works fine, but all it's doing is converting the string to a string, and then calling html_safe. When I know I have a string, I prefer calling html_safe directly, because it skips an unnecessary step and makes it clearer ...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...
In [9]: pd.Series(df.Letter.values,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e'}
Speed comparion (using Wouter's method)
In [6]: df = pd.DataFrame(randint(0,10,10000).reshape(5000,2),columns=list('AB'))
In [7]:...
How to get line count of a large file cheaply in Python?
... way to make this run considerably faster, namely by using the unbuffered (raw) interface, using bytearrays, and doing your own buffering. (This only applies in Python 3. In Python 2, the raw interface may or may not be used by default, but in Python 3, you'll default into Unicode.)
Using a modifi...
Quickly reading very large tables as dataframes
...'s my test code:
Set up the test data:
bigdf <- data.frame(dim=sample(letters, replace=T, 4e7), fact1=rnorm(4e7), fact2=rnorm(4e7, 20, 50))
write.csv(bigdf, 'bigdf.csv', quote = F)
I restarted R before running the following import routine:
library(sqldf)
f <- file("bigdf.csv")
system.time...
Group by multiple columns in dplyr, using string vector input
...elect, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 &l...
File Upload without Form
... named file with properties of file_field to form_data
form_data.append("user_id", 123) // Adding extra parameters to form_data
$.ajax({
url: "/upload_avatar", // Upload Script
dataType: 'script',
cache: false,
contentType: false,
processData: false,
data: form_data, // S...
What does the 'Z' mean in Unix timestamp '120314170138Z'?
...rdinated_Universal_Time:
The UTC time zone is sometimes denoted by the letter Z—a reference to
the equivalent nautical time zone (GMT), which has been denoted by a Z
since about 1950. The letter also refers to the "zone description" of
zero hours, which has been used since 1920 (see time...
How to get std::vector pointer to the raw data?
...ckoverflow.com%2fquestions%2f6485496%2fhow-to-get-stdvector-pointer-to-the-raw-data%23new-answer', 'question_page');
}
);
Post as a guest
Name
...
What is a “slug” in Django?
...year-old-virgin is a slug: it is created from the title by down-casing all letters, and replacing spaces by hyphens -.
Also see the URL of this very web page for another example.
share
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improve t...
Convert the values in a column into row names in an existing data frame
... assign rowname attributes, then remove column:
R> df<-data.frame(a=letters[1:10], b=1:10, c=LETTERS[1:10])
R> rownames(df) <- df[,1]
R> df[,1] <- NULL
R> df
b c
a 1 A
b 2 B
c 3 C
d 4 D
e 5 E
f 6 F
g 7 G
h 8 H
i 9 I
j 10 J
R>
...