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Split (explode) pandas dataframe string entry to separate rows
...lumn of text strings contains comma-separated values. I want to split each CSV field and create a new row per entry (assume that CSV are clean and need only be split on ','). For example, a should become b :
...
Rails: How does the respond_to block work?
...# index.html.erb
format.json { render :json => @posts }
format.csv { render :csv => @posts }
format.js
end
end
The csv line will cause to_csv to be called on each post when you visit /posts.csv. This makes it easy to export data as CSV (or any other format) from your rails ...
How to use the “number_to_currency” helper method in the model rather than view?
...in Sam’s answer.
If you think “but I really need this to write my to_csv & to_pdf methods in my model!”, then your entire premise is wrong—after all, you don’t have a to_html method, do you? And yet your object is very often rendered as HTML. Consider creating a new class for generat...
How can I combine multiple rows into a comma-delimited list in Oracle? [duplicate]
...('Antigua');
SELECT SUBSTR (SYS_CONNECT_BY_PATH (country_name , ','), 2) csv
FROM (SELECT country_name , ROW_NUMBER () OVER (ORDER BY country_name ) rn,
COUNT (*) OVER () cnt
FROM countries)
WHERE rn = cnt
START WITH rn = 1
CONNECT BY rn = PRIOR rn + 1;
...
LINQ Aggregate algorithm explained
...in sequence) to make 6. Then adds 6 and 4 to make 10.
Example 2. create a csv from an array of strings
var chars = new []{"a","b","c", "d"};
var csv = chars.Aggregate( (a,b) => a + ',' + b);
Console.WriteLine(csv); // Output a,b,c,d
This works in much the same way. Concatenate a a comma and b...
创业 比“直男癌”更可怕的是“技术癌” - 资讯 - 清泛网 - 专注C/C++及内核技术
...垒。例如，我们AA投资上半年投资的玩美自由行，它以大数据技术和强大的分析算法为支撑，可以让用户在一分钟之内，通过简单的四步定制出性化的出境自由行，是一个极富竞争力的创业项目。更重要的是，玩美自由行项目最...
Postgresql GROUP_CONCAT equivalent?
...method, if they are not desired.
Casting ANYARRAY to TEXT best simulates CSV output as elements that contain embedded commas are double-quoted in the output in standard CSV style. Neither array_to_string() or string_agg() (the "group_concat" function added in 9.1) quote strings with embedded comma...
MySQL dump by query
...
You can dump a query as csv like this:
SELECT * from myTable
INTO OUTFILE '/tmp/querydump.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
share
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Filtering Pandas DataFrames on dates
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So when loading the csv data file, we'll need to set the date column as index now as below, in order to filter data based on a range of dates. This was not needed for the now deprecated method: pd.DataFrame.from_csv().
If you just want to show ...
reformat in vim for a nice column layout
I have this dataset in a csv file
13 Answers
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