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Python Pandas: Get index of rows which column matches certain value
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df.iloc[i] returns the ith row of df. i does not refer to the index label, i is a 0-based index.
In contrast, the attribute index returns actual index labels, not numeric row-indices:
df.index[df['BoolCol'] == True].tolist()
or equivalently,
df.index[df['BoolCol']].tolist()
You can see...
Switch statement fall-through…should it be allowed? [closed]
... case 8:
result = EVEN_DIGIT;
break;
}
But if you have a case label followed by code that falls through to another case label, I'd pretty much always consider that evil. Perhaps moving the common code to a function and calling from both places would be a better idea.
And please note t...
How to add manifest permission to an application?
...id:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@android:style/Theme.Black.NoTitleBar" >
<activity
android:name="com.photoeffect.MainActivity"
android:label="@string/app_name" >
<intent-fil...
程序员之网络安全系列（三）：数据加密之对称加密算法 - 更多技术 - 清泛网...
...王不冒充明明？（身份认证)
如何保证明明不能否认情书是自己写的？（来源的不可否认)
上一节，我们使用了Hash算法保证了情书的完整性，也就是确保“隔壁王叔叔”没有修改明明的情书，那么这一节我们来看看如何保证...
What is the meaning of #XXX in code comments?
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Do you know if PEP350 is the origin of these labels? Do you know any older documents (from the Unix era) describing how to use these labels?
– Ярослав Рахматуллин
Aug 31 '18 at 8:26
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Is a one column table good design? [closed]
...ULL DEFAULT AUTOINCREMENT, "master_entry_id" INTEGER NULL, "master_entry_label" VARCHAR(200) NULL, "language_id" INTEGER NULL, "localised_entry_label" VARCHAR(300) NULL,
– Vincent Buck
Jun 5 '09 at 12:01
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Difference between Control Template and DataTemplate in WPF
...trol while a DataTemplate describes how to display Data.
For example:
A Label is a control and will include a ControlTemplate which says the Label should be displayed using a Border around some Content (a DataTemplate or another Control).
A Customer class is Data and will be displayed using a D...
Check if UIColor is dark or bright?
...il)
return white > 0.5
}
}
// Usage
if color.isLight {
label.textColor = UIColor.black
} else {
label.textColor = UIColor.white
}
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Should I use a data.frame or a matrix?
...ing via as.matrix() will result in a character matrix if any of the factor labels is non-numeric. Compare:
> head(as.matrix(data.frame(a = factor(letters), B = factor(LETTERS))))
a B
[1,] "a" "A"
[2,] "b" "B"
[3,] "c" "C"
[4,] "d" "D"
[5,] "e" "E"
[6,] "f" "F"
> head(data.matrix(data...
Android - Back button in the title bar
... android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="@string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<!-- Parent activity meta-data to support 4.0 and lower -->
<meta-data
android:...