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R - Concatenate two dataframes?
...rbind but in this case you need to have the same number of columns in both tables, so try the following:
b$b<-as.double(NA) #keeping numeric format is essential for further calculations
new<-rbind(a,b)
share
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Python unittest - opposite of assertRaises?
...the correct solution in fact. The solution proposed by user9876 is conceptually flawed: if you test for the non-raising of say ValueError, but ValueError is instead raised, your test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise ...
How to make inline functions in C#
...=> x + y;
void print(int x) { Console.WriteLine(x); }
There are basically two different types for these: Func and Action. Funcs return values but Actions don't. The last type parameter of a Func is the return type; all the others are the parameter types.
There are similar types with different...
How to convert byte array to string [duplicate]
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This answer saves readers the inevitable google search for the other conversion direction.
– Zoomzoom
Jul 25 '18 at 13:08
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How to create a video from images with FFmpeg?
...pix_fmt yuv420p out.ogg
Your images should of course be sorted alphabetically, typically as:
0001-first-thing.jpg
0002-second-thing.jpg
0003-and-third.jpg
and so on.
I would also first ensure that all images to be used have the same aspect ratio, possibly by cropping them with imagemagick or n...
Get position/offset of element relative to a parent container?
...ch mobiles do not support it I would be interested (can't find any support table for mobiles about it).
– Nobita
Jul 1 '14 at 11:54
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Java logical operator short-circuiting
...nown as short-circuit logical operators. As you can see from the preceding table, the OR operator results in true when A is true, no matter what B is.
Similarly, the AND operator results in false when A is false, no matter what B is. If you use the || and && forms, rather than the | and &am...
GCC dump preprocessor defines
...nstead of the normal output, generate
a list of `#define' directives for all
the macros defined during the
execution of the preprocessor,
including predefined macros. This
gives you a way of finding out what is
predefined in your version of the
preprocessor. Assuming you have no
file...
How to import the class within the same directory or sub directory?
I have a directory that stores all the .py files.
13 Answers
13
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How to invoke the super constructor in Python?
In all other languages I've worked with the super constructor is invoked implicitly. How does one invoke it in Python? I would expect super(self) but this doesn't work.
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