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Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith value in the Btime column you could use:
In ...
Correct way to close nested streams and writers in Java [duplicate]
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I usually do the following. First, define a template-method based class to deal with the try/catch mess
import java.io.Closeable;
import java.io.IOException;
import java.util.LinkedList;
import java.util.List;
public abstract cl...
Ruby, remove last N characters from a string?
...alternative, and hope it helps people who land here. In fact, I've covered all this in the question - I'm hoping this method accepts a regex soon, though there's a perfect alternative for your case right below this.
– SRack
Sep 2 '19 at 15:07
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best way to get the key of a key/value javascript object
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If you want to get all keys, ECMAScript 5 introduced Object.keys. This is only supported by newer browsers but the MDC documentation provides an alternative implementation (which also uses for...in btw):
if(!Object.keys) Object.keys = function...
OS X10.9 环境下部署 QT5.3.1 常见的编译问题 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...件中加入对应的SDK版本:
1
QMAKE_MAC_SDK = macosx10.9
3、:-1: error: [ui_mainwindow.h] Trace/BPT trap: 5
dyld: Library not loaded: /work/build/______________________________PADDING______________________________/lib/QtCore.framework/Versio...
Rotation methods deprecated, equivalent of 'didRotateFromInterfaceOrientation'?
... new viewWillTransitionToSize method which has been introduced in iOS 8 (all other rotation methods have been deprecated). I'd like to know what the equivalent of didRotateFromInterfaceOrientation is now as there are a number of clean up tasks we need to perform and I can't see a block that we c...
How would you access Object properties from within an object method? [closed]
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PHP offers a myriad of ways to handle this, including magic methods __get and __set, but I prefer explicit getters and setters. Here's why:
Validation can be placed in setters (and getters for that matter)
Intellisense works with explicit methods
No question whether a property is read only,...
what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
... string key
}
}
Method 1: JSON.parse - symbolizes all keys recursively => Does not preserve original mix
JSON.parse( h.to_json, {:symbolize_names => true} )
=> { :youtube => { :search=> "daffy", :history => ["goofy", "mickey"] } }
Method 2: ActiveSup...
Why is there “data” and “newtype” in Haskell? [duplicate]
...peek inside.
Couldn't the compiler handle this for itself.
No, not really—this is a case where as the programmer you get to decide whether the constructor is strict or lazy. To understand when and how to make constructors strict or lazy, you have to have a much better understanding of lazy ...
error LNK2019: 无法解析的外部符号 __imp__PlaySoundW@12，该符号在函数 \...
error LNK2019: 无法解析的外部符号 __imp__PlaySoundW@12，该符号在函数 "long __stdcall WndProc(struct HWND__ *,unsigned int,unsigned int,long)" (?WndProc@@YGJPAUHWND__@@IIJ@Z) 中被引用#include <mmsystem.h>#pragma comment(lib, "WINMM.LIB")
#include <mmsystem.h>
#pragma comm...