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Way to read first few lines for pandas dataframe
Is there a built-in way to use read_csv to read only the first n lines of a file without knowing the length of the lines ahead of time? I have a large file that takes a long time to read, and occasionally only want to use the first, say, 20 lines to get a sample of it (and prefer not to load the...
Converting Select results into Insert script - SQL Server [closed]
... part i
--have used below variable
------@CSV_COLUMN-------
values(Col1 data in quote, Col2..quote,..Col5..quote)
-- To achieve this part
-- i.e column data in
--quote i have used
--below variable
----@QUOTED_DATA---
C)To get above data from existing
table ...
Good reasons NOT to use a relational database?
..., but with a bit more ability to validate the structure.
Spreadsheet / CSV file
Very easy model for business users to understand
Subversion (or similar disk based version control system)
Very good support for versioning of data
Berkeley DB (Basically, a disk based hashtable)
Very s...
python pandas remove duplicate columns
...probably with the duplicate column titles.
For a sample table file 'dummy.csv' I made up:
Time H1 N2 Time N2 Time Relative
3 13 13 3 13 0
1 15 15 1 15 14
14 19 19 14 19 14
19 5 5 19 5 1
using read_table gives unique columns and works properly:
In [151]: df2 =...
Alternative to google finance api [closed]
...hoo Finance API posted on
Google Code.
For beginners, you can generate a CSV with a simple API call:
http://finance.yahoo.com/d/quotes.csv?s=AAPL+GOOG+MSFT&f=sb2b3jk
(This will generate and save a CSV for AAPL, GOOG, and MSFT)
Note that you must append the format to the query string (f=..)...
UnicodeDecodeError: 'utf8' codec can't decode byte 0x9c
...g the engine from C to Python did the trick for me.
Engine is C:
pd.read_csv(gdp_path, sep='\t', engine='c')
'utf-8' codec can't decode byte 0x92 in position 18: invalid start byte
Engine is Python:
pd.read_csv(gdp_path, sep='\t', engine='python')
No errors for me.
...
Generating an Excel file in ASP.NET [closed]
...
CSV
Pros:
Simple
Cons:
It may not work in other locales or in different Excel configurations (i.e. List separator)
Can't apply formatting, formulas, etc
HTML
Pros:
Still pretty Simple
Supports simple format...
C#中数组、ArrayList和List三者的区别 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...List< T> 始终只具有一个维度。但是，您可以轻松创建数组列表或列表的列表。特定类型（Object 除外）的数组 的性能优于 ArrayList的性能。 这是因为 ArrayList的元素属于 Object 类型；所以在存储或检索值类型时通常发生装箱和取消...
C#泛型(List)中基类和子类 怎么转换？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ChildClass> childList = ...Foo(List<BaseClass> baseList);需求：把子类列表传入函数Foo，Foo支持所有子类列表。方法一：Foo(ch...List<ChildClass> childList = ...
Foo(List<BaseClass> baseList);
需求：把子类列表传入函数Foo，Foo支持所有子类列表。
方法...
App Inventor 2 手机蓝牙及语音控制 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
...过程】 一、蓝牙知识准备
1. APP相关知识
列表选择框组件：便于用户从预设的条目中选择，如选择与手机配对的外部蓝牙设备；
蓝牙客户端组件：用于建立手机蓝牙与外部蓝牙设备的配对连接，并向外部蓝牙...