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How should I escape commas and speech marks in CSV files so they work in Excel?
I'm generating a CSV file (delimited by commas rather than tabs). My users will most likely open the CSV file in Excel by double clicking it. My data may contain commas and speech marks, so I'm escaping those as follows.
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How do I make a list of data frames?
... is done pretty easily when reading in files. Maybe you've got files data1.csv, data2.csv, ... in a directory. Your goal is a list of data.frames called mydata. The first thing you need is a vector with all the file names. You can construct this with paste (e.g., my_files = paste0("data", 1:5, ".csv...
How to write DataFrame to postgres table?
...s DB much faster than df.to_sql method and you won't need any intermediate csv file to store the df.
Create an engine based on your DB specifications.
Create a table in your postgres DB that has equal number of columns as the Dataframe (df).
Data in DF will get inserted in your postgres table.
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App Inventor 2在不同的屏幕之间传值 · App Inventor 2 中文网
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通过原生控制块“打开屏幕并传值”
列表传值
微数据库传值
« 返回首页
App Inventor 2 在不同的屏幕之间传值属于很常见的需求，这里提供各种不同的实现思路，供大家参考。
通过原生控制块“打开屏幕...
MIT已发布v2.75版本，中文网已同步升级最新版本 - App Inventor 2 中文网 -...
...习和使用，才能与大家分享。
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列表显示框组件有进一步的改进在上个版本（2022）中，列表显示框可以同时显示图片、主项及细项三部分内容，这个版本延续了这一功能，并在显示样式方面做了一些改进...
Output data from all columns in a dataframe in pandas [duplicate]
I have a csv file with the name params.csv . I opened up ipython qtconsole and created a pandas dataframe using:
7 Ans...
How to create a file in memory for user to download, but not through server?
... a download prompt. Otherwise, it will probably open in the browser.
For CSV, you can use:
<a href="data:application/octet-stream,field1%2Cfield2%0Afoo%2Cbar%0Agoo%2Cgai%0A">CSV Octet</a>
Try the jsFiddle demo.
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Only read selected columns
....g.: fread("data.txt", select = c(1:7), data.table = FALSE)
2) With read.csv.sql from the sqldf-package:
Another alternative is the read.csv.sql function from the sqldf package:
library(sqldf)
dat <- read.csv.sql("data.txt",
sql = "select Year,Jan,Feb,Mar,Apr,May,Jun from ...
source of historical stock data [closed]
...IS NO LONGER ACCURATE AS THE YAHOO FEED HAS CEASED TO EXIST
Using Yahoo's CSV approach above you can also get historical data!
You can reverse engineer the following example:
http://ichart.finance.yahoo.com/table.csv?s=YHOO&d=0&e=28&f=2010&g=d&a=3&b=12&c=1996&ignore...
How to convert a List into a comma separated string without iterating List explicitly [dupli
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With Java 8:
String csv = String.join(",", ids);
With Java 7-, there is a dirty way (note: it works only if you don't insert strings which contain ", " in your list) - obviously, List#toString will perform a loop to create idList but it does n...