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How to calculate the angle between a line and the horizontal axis?
... the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividing the differences this way will erase the distinction needed to distinguish which quadrant the angle is in (see below). Use the following instead if your language includes ...
Inline elements shifting when made bold on hover
...
401
li {
display: inline-block;
font-size: 0;
}
li a {
display:inline-block;
...
SQL Logic Operator Precedence: And and Or
...e's an example to illustrate:
Declare @x tinyInt = 1
Declare @y tinyInt = 0
Declare @z tinyInt = 0
Select Case When @x=1 OR @y=1 And @z=1 Then 'T' Else 'F' End -- outputs T
Select Case When (@x=1 OR @y=1) And @z=1 Then 'T' Else 'F' End -- outputs F
For those who like to consult references (in al...
Days between two dates? [duplicate]
...er of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> (a-b).days
7
And it works with datetimes too — I think it rounds down to the nearest day:
>>> from datetime import...
Is 'float a = 3.0;' a correct statement?
...
It is not an error to declare float a = 3.0 : if you do, the compiler will convert the double literal 3.0 to a float for you.
However, you should use the float literals notation in specific scenarios.
For performance reasons:
Specifically, consider:
float foo(...
Vagrant's port forwarding not working [closed]
...
80
I'll make this an actual answer instead of just more comments.
First thing: try curl 'http://lo...
How can you profile a Python script?
...e.bat':
python -m cProfile %1
So all I have to do is run:
profile euler048.py
And I get this:
1007 function calls in 0.061 CPU seconds
Ordered by: standard name
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.000 0.000 0.061 0.061 <string>:1(&lt...
Logical operators for boolean indexing in Pandas
...
When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x']==1) and (a['y']==10) to boolean values.
NumPy arrays (of length greater than 1) and Pandas objects such as Series do not have a boolean value -- in other words, they ...
Fastest way to reset every value of std::vector to 0
...at's the fastest way to reset every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 Answ...
Initialise a list to a specific length in Python [duplicate]
How do I initialise a list with 10 times a default value in Python?
3 Answers
3
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