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Is it possible to specify condition in Count()?
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what if my field is integer and I want to match null. it doesn't work this way select count(case IntegerField when 'NULL' then 1 else null end) from
– Faizan
Aug 31 '16 at 10:16
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matplotlib does not show my drawings although I call pyplot.show()
...xa64932c>]
In [3]: p.show()
If you edit ~/.matplotlib/matplotlibrc and change the backend to something like GtkAgg, you should see a plot. You can list all the backends available on your machine with
import matplotlib.rcsetup as rcsetup
print(rcsetup.all_backends)
It should return a list ...
Shading a kernel density plot between two points.
...ently use kernel density plots to illustrate distributions. These are easy and fast to create in R like so:
5 Answers
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Difference between method and function in Scala
...cification tell us. Chapter 3 (types) tell us about Function Types (3.2.9) and Method Types (3.3.1). Chapter 4 (basic declarations) speaks of Value Declaration and Definitions (4.1), Variable Declaration and Definitions (4.2) and Functions Declarations and Definitions (4.6). Chapter 6 (expressions) ...
ArithmeticException: “Non-terminating decimal expansion; no exact representable decimal result”
... setting of a MathContext object with a precision setting of 0 is not used and thus irrelevant. In the case of divide, the exact quotient could have an infinitely long decimal expansion; for example, 1 divided by 3.
If the quotient has a nonterminating decimal expansion and the operation is specifie...
How to check permissions of a specific directory?
... it does:
-d, --directory
list directory entries instead of contents, and do not dereference symbolic links
You might be interested in manpages. That's where all people in here get their nice answers from.
refer to online man pages
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A beginner's guide to SQL database design [closed]
...fmann Series in Data Management Systems) (Paperback) by Jan L. Harrington and found it very clear and helpful
and as you get up to speed this one was good too Database Systems: A Practical Approach to Design, Implementation and Management (International Computer Science Series) (Paperback)
I thin...
Common use-cases for pickle in Python
I've looked at the pickle documentation, but I don't understand where pickle is useful.
9 Answers
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Why do we need boxing and unboxing in C#?
Why do we need boxing and unboxing in C#?
11 Answers
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Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...