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How to change the order of DataFrame columns?
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34 Answers
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Difference between map, applymap and apply methods in Pandas
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Straight from Wes McKinney's Python for Data Analysis book, pg. 132 (I highly recommended this book):
Another frequent operation is applying a function on 1D arrays to each column or row. DataFrame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3),...
typedef fixed length array
I have to define a 24-bit data type.I am using char[3] to represent the type. Can I typedef char[3] to type24 ? I tried it in a code sample. I put typedef char[3] type24; in my header file. The compiler did not complain about it. But when I defined a function void foo(type24 val) {} in my C...
Why is address zero used for the null pointer?
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edited May 3 '10 at 17:44
answered May 3 '10 at 17:22
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List comprehension vs map
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$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely reversed when map needs a lambda:
$ pytho...
JavaScript function similar to Python range()
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23 Answers
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How to make a great R reproducible example
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Pass a variable into a partial, rails 3?
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237
Try this:
<% @posts.each do |post| %>
<%= render 'middle', :post => post %>
&...
Converting many 'if else' statements to a cleaner approach [duplicate]
...h Mimetype like:
public interface Converter {
public void convertToMp3();
public void convertToOgg();
}
public class MpegConverter implements Converter {
public void convertToMp3() {
//Code here
}
public void convertToOgg() {
//Code here
}
}
You would...