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How do you calculate the average of a set of circular data? [closed]
... sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably programmatically more efficient, and also work well in the zero case, so kudos to him.
The subject is now explored in more detail on Wikipedia, and with other uses, l...
Converting between datetime, Timestamp and datetime64
...>> numpy.__version__
'1.6.2' # current version available via pip install numpy
I can reproduce the long value on numpy-1.8.0 installed as:
pip install git+https://github.com/numpy/numpy.git#egg=numpy-dev
The same example:
>>> from datetime import datetime
>>> import num...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
...
std::enable_if to conditionally compile a member function
... I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
7 Answers
...
hasNext in Python iterators?
...thod to put the first element back after I have checked that it exists by calling next().
– Giorgio
Dec 24 '12 at 20:26
16
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What are the most common naming conventions in C?
...I follow the GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_p...
Mongoose populate after save
I cannot manually or automatically populate the creator field on a newly saved object ... the only way I can find is to re-query for the objects I already have which I would hate to do.
...
How to set child process' environment variable in Makefile
...
I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
Where in a virtualenv does the custom code go?
... instance, if I were building a WSGI application and created a virtualenv called foobar I would start with a directory structure like:
...
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...