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My apologies that I don't use always use programming terms in my description - I am a musician who has only dabbled in programming.
Suppose I have a list of numbers named a:
a = (0, 2, 4, 5, 7, 9, 11, 12)
and from the list a the following list of numbers is randomly generated to create list b:
b = (4, 7, 5, 7, 9, 11, 9)
Then I want to have "transpositions" (this is a musical term) of list b, such as those shown in lists c, d, and e:
c = (5, 9, 7, 9, 11, 12, 11) or d = (2, 5, 4, 5, 7, 9, 11, 9) or e = (0, 4, 2, 4, 5, 7, 9, 7)
What do you call this "transposition" of this list of numbers in programming terms, and what bit of programming code would accomplish this task? My best guess is that it has to do with the indexing of the numbers in list a, and when list b is created the indexes of list b are put in a list such as list f:
f = (2, 4, 3, 4, 5, 6, 5)
so that the "transposition" is accomplished by adding or subtracting a specific number from each number in list f. For example, the numbers in list c are generated by adding 1 to each of the numbers in list f:
(3, 5, 4, 5, 6, 7, 6)
the numbers in list d are generated by subtracting 1 to each of the numbers in list f:
(1, 3, 2, 3, 4, 5, 4)
and the numbers in list e are generated by subtracting 2 to each of the index numbers taken from list f:
(0, 2, 1, 2, 3, 4, 3)
Or if anyone has a better idea, please let me know.
An operation like "add 1 to every member of this list, to generate a new list" is usually called a map.
An ordinary way to make a tuple in Julia is like this:
n = 5
t2 = (n,n) # t2 = (5,5)
t3 = (n,n,n)# t3 = (5,5,5)
I want to make a tuple of arbitrary size functionally.
n = 5
someFunction(n,size) = ???
t10 = someFunction(n,10) # t10 = (5,5,5,5,5,5,5,5,5,5)
How can I realize this?
Any information would be appreciated.
Maybe what you are looking for is ntuple ?
julia> ntuple(_ -> 5, 10)
(5, 5, 5, 5, 5, 5, 5, 5, 5, 5)
Note that, you can also use tuple or Tuple:
julia> tuple((5 for _ in 1:10)...)
(5, 5, 5, 5, 5, 5, 5, 5, 5, 5)
julia> Tuple(5 for _ in 1:10)
(5, 5, 5, 5, 5, 5, 5, 5, 5, 5)
I have a table named flup and some datas like:
pid, flup_time, degree, oc, flup_type
1, 2018-05-06, 1, 0, 2
1, 2018-08-01, 2, 0, 3
1, 2018-08-13, 2, 0, 1
1, 2018-08-25, 2, 1, 1
1, 2018-11-20, 2, 1, 2
1, 2019-01-09, 2, 1, 2
2, 2018-06-01, 1, 0, 2
2, 2018-08-27, 2, 0, 2
2, 2018-11-30, 2, 0, 2
...
First, find all datas group by pid, for this pid (here pid=1), order by flup_time asc. Give a period of time (like from 2018-01-01 to 2019-07-01), for every row, make rules:
rule1. if degree = 1, then next flup_time must in 90 days.
rule2. if degree = 2 and oc != 1, then next flup_time must in 15 days.
rule3. if degree = 2 and oc = 1, then next flup_time must in 90 days.
I want to create a view (flup_view), has all the columns of flup, and more column named pass_check. If the row met the rule1,2,3, pass_check = 1, otherwise pass_check = 2. Like:
pid, flup_time, degree, oc, flup_type, pass_check
1, 2018-05-06, 1, 0, 2, -1
1, 2018-08-01, 2, 0, 3, 1
1, 2018-08-13, 2, 0, 1, 1
1, 2018-08-25, 2, 1, 1, 1
1, 2018-11-20, 2, 1, 2, 1
1, 2019-01-09, 2, 1, 2, 1
2, 2018-06-01, 1, 0, 2, -1
2, 2018-08-27, 2, 0, 2, 1
2, 2018-11-30, 2, 0, 2, 2
How to do this by sql please?
There are a couple of pieces that you'll need for this to work. I'm not sure how strong your SQL background is, so I'll include the basics as well.
First, in order to create the rule, you'll need to use a CASE WHEN:
https://www.w3schools.com/sql/func_mysql_case.asp
Next, you need to get the following row for each ID, you need to use the LEAD function. Here's a general overview:
https://dev.mysql.com/doc/refman/8.0/en/window-function-descriptions.html
and a tutorial for LAG, which is the same as LEAD, but it checks the row above rather than the row below:
http://www.mysqltutorial.org/mysql-window-functions/mysql-lag-function/
(LEAD didn't exist in early version of MySQL, so your version might not have this)
Finally, you want to compare dates using the DATE_ADD function:
https://www.w3schools.com/sql/func_mysql_date_add.asp
It will be a little complicated, but these three things should be enough to let you build the query you need.
I have a list of tuples looking like this:
import datetime as dt
hours = [(dt.datetime(2019,3,9,23,0), dt.datetime(2019,3,10,22,0)),
(dt.datetime(2019,3,10,23,0), d.datetime(2019,3,11,22,0))]
The list has a variable length and I just need a boolean if datetime.now() is between the first and second element of any tuple in the list.
In NumPy I would do:
((start <= now) & (end >= now)).any()
what is the most efficient way to do this in a pythonic way? Sorry about the beginners question.
this works but I don't like the len():
from itertools import takewhile
len(list(takewhile(lambda x: x[0] <= now and now <= x[1], hours ))) > 0
any better suggestions?
any(map(lambda d: d[0] <= now <= d[1], hours))
any: Logical OR across all elements
map: runs a function on every element of the list
As #steff pointed out map is redundant, because we cause list enumeration directly.
any(d[0] <= now <= d[1] for d in hours)
It would be way better if we can avoid indexing into tuple and use tuple unpacking somehow (this was the reason I started with map)
A more verbose alternative. (But more readable in my eyes)
import datetime as dt
def in_time_ranges(ranges):
now = dt.datetime.now()
return any([r for r in ranges if now <= r[0] and r[1] >= now])
ranges1 = [(dt.datetime(2019, 3, 9, 23, 0), dt.datetime(2019, 3, 10, 22, 0)),
(dt.datetime(2019, 3, 10, 23, 0), dt.datetime(2019, 3, 11, 22, 0)),
(dt.datetime(2019, 4, 10, 23, 0), dt.datetime(2019, 5, 11, 22, 0))]
print(in_time_ranges(ranges1))
ranges2 = [(dt.datetime(2017, 3, 9, 14, 0), dt.datetime(2018, 3, 10, 22, 0)),
(dt.datetime(2018, 3, 10, 23, 0), dt.datetime(2018, 3, 11, 22, 0)),
(dt.datetime(2018, 4, 10, 23, 0), dt.datetime(2018, 5, 11, 22, 0))]
print(in_time_ranges(ranges2))
Output
True
False
I am trying to do a mysql sort that displays 0 first and then by the largest number.
My current mysql statement returns
10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 0, 0
But I would like to get this
0, 0, 0, 0, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1
Is it possible to build a MySQL query that orders an integer from largest to smallest with 0 at the beginning?
Try this order by statement:
order by val = 0 desc, val desc
The first part is a boolean that evaluates to "1" when the value is 1 and otherwise 0. The second orders the rest of the values in descending order.
you have to use 2 filters
select * from mytable
order by mycolumn=0 desc, mycolumn desc