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Create code first, many to many, with additional fields in association table
... you now want to find all comments of members with LastName = "Smith" for example you can write a query like this:
var commentsOfMembers = context.Members
.Where(m => m.LastName == "Smith")
.SelectMany(m => m.MemberComments.Select(mc => mc.Comment))
.ToList();
... or ...
var...
Why not be dependently typed?
...d language". The implication seems to be that with more and more language extensions, Haskell is drifting in that general direction, but isn't there yet.
...
What is the difference between linear regression and logistic regression?
...c.
Equation
Linear regression gives an equation which is of the form Y = mX + C,
means equation with degree 1.
However, logistic regression gives an equation which is of the form
Y = eX + e-X
Coefficient interpretation
In linear regression, the coefficient interpretation of independent variable...
Adding a regression line on a ggplot
...
In general, to provide your own formula you should use arguments x and y that will correspond to values you provided in ggplot() - in this case x will be interpreted as x.plot and y as y.plot. More information about smoothing methods and formula you can find in help page of function stat_s...
bool operator ++ and --
...
It comes from the history of using integer values as booleans.
If x is an int, but I am using it as a boolean as per if(x)... then incrementing will mean that whatever its truth value before the operation, it will have a truth-value of true after it (barring overflow).
However, it's impossi...
How to remove the first Item from a list?
...
Python List
list.pop(index)
>>> l = ['a', 'b', 'c', 'd']
>>> l.pop(0)
'a'
>>> l
['b', 'c', 'd']
>>>
del list[index]
>>> l = ['a', 'b', 'c', 'd']
>>> del l[0]
>>> l
['b', 'c', 'd']
&g...
Why is it slower to iterate over a small string than a small list?
...doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
...
How can I get the intersection, union, and subset of arrays in Ruby?
...- other.set
end
# union
def |(other)
@set | other.set
end
end
x = MultiSet.new([1,1,2,2,3,4,5,6])
y = MultiSet.new([1,3,5,6])
p x - y # [2,2,4]
p x & y # [1,3,5,6]
p x | y # [1,2,3,4,5,6]
share
|
...
How to do exponentiation in clojure?
How can I do exponentiation in clojure?
For now I'm only needing integer exponentiation, but the question goes for fractions too.
...
How to round a number to significant figures in Python
...t:
>>> from math import log10, floor
>>> def round_to_1(x):
... return round(x, -int(floor(log10(abs(x)))))
...
>>> round_to_1(0.0232)
0.02
>>> round_to_1(1234243)
1000000.0
>>> round_to_1(13)
10.0
>>> round_to_1(4)
4.0
>>> round_to_...