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How to pick just one item from a generator?
... would use the second syntax given in my answer, next(g). This will internally call g.__next__(), but you don't really have to worry about that, just as you usually don't care that len(a) internally calls a.__len__().
– Sven Marnach
Apr 10 '14 at 10:31
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Converting strings to floats in a DataFrame
...newer version of pandas (0.17 and up), you can use to_numeric function. It allows you to convert the whole dataframe or just individual columns. It also gives you an ability to select how to treat stuff that can't be converted to numeric values:
import pandas as pd
s = pd.Series(['1.0', '2', -3])
p...
How do I add a placeholder on a CharField in Django?
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Look at the widgets documentation. Basically it would look like:
q = forms.CharField(label='search',
widget=forms.TextInput(attrs={'placeholder': 'Search'}))
More writing, yes, but the separation allows for better abstraction of more complic...
What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?
...ased presentation framework.
JavaServer Pages is a view technology used by all mentioned presentation framework for the view.
Tapestry is another component-based presentation framework.
So, to summarize:
Struts 2, JSF, Tapestry (and Wicket, Spring MVC, Stripes) are presentation frameworks. If yo...
How to read a file into a variable in shell?
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Ok but it's bash, not sh; it may not fit all cases.
– moala
Apr 15 '13 at 11:25
18
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How can I get nth element from a list?
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Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
How to get the Power of some Integer in Swift language?
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I really like this solution, but with Swift 3 it does not work. Any idea how to make it work?
– Vanya
Sep 19 '16 at 18:51
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Colspan all columns
How can I specify a td tag should span all columns (when the exact amount of columns in the table will be variable/difficult to determine when the HTML is being rendered)? w3schools mentions you can use colspan="0" , but it doesn't say exactly what browsers support that value (IE 6 is in our li...
Undefined symbols for architecture i386: _OBJC_CLASS_$_SKPSMTPMessage", referenced from: error
...r the "Compile Sources" step of the "Build Phases" tab of your target. Normally Xcode does this for you, but sometimes it loses the plot and you need to add the .m file manually.
To do this:
TargetSettings -> Build Phases -> Compile Sources -> add your .m class ->Build and Run
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Get source jar files attached to Eclipse for Maven-managed dependencies
...ou can configure it to download both the source files and javadoc automatically for you.
This is achieved by going into Window > Preferences > Maven and checking the "Download Artifact Sources" and "Download Artifact JavaDoc" options.
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