So I this code which is suppose to return a list with the closest leap year of a list of years.
For example: calling the function with [1995 1750 2018] should return
1996 1748 2016
Which it does for that set of numbers.
The problem I am having is that when a leap year is in the input for example 2008 it does not give me back the closest leap year to 2008. I get back 2008.
Any suggestions as to how I can modify the code to make it work?
code
def is_leap(year):
leap = False
if year % 4 == 0:
if year % 100 != 0 or year % 400 == 0:
leap = True
return leap
major_b = []
major_f = []
newLst = []
def year_forward(yearBounds):
for item in yearBounds:
counter = 0
while not is_leap(item):
item = item + 1
counter += 1
major_f.append([item, counter])
return major_f
def year_backward(yearBounds):
for item in yearBounds:
counter = 0
while not is_leap(item):
item = item - 1
counter -= 1
major_b.append([item,counter])
return major_b
def findLastLeapYears(yearBounds):
forward = year_forward(yearBounds)
backward = year_backward(yearBounds)
counter = 0
for item in forward:
if abs(item[1]) < abs(backward[counter][1]):
newLst.append (str(item[0]))
counter+=1
elif abs(item[1]) == abs(backward[counter][1]):
if item[0] < backward[counter][0]:
newLst.append (str(item[0]))
counter += 1
else:
newLst.append (str(backward[counter][0]))
counter += 1
else:
newLst.append (str(backward[counter][0]))
counter+=1
return newLst
I'd avoid trying to roll your own leap year detection code. Use calendar.isleap to determine whether a year is a leap year or not.
Then go in a loop, like this:
import calendar
def find_nearest_leap(year):
offset = 1
while True:
if calendar.isleap(year - offset):
return year - offset
if calendar.isleap(year + offset):
return year + offset
offset += 1
To find the list of nearest leap years for a list of values, do this:
nearest_leap_years = [find_nearest_leap(year) for year in years]
Where years is the list of years you are interested in.
I'm also assuming the nearest leap year isn't the year itself, which seems to be a constraint of the problem...
Related
I'm trying to extract climate data from various .nc files I have but the process is taking extremely long, I suspect it has something to do with the fact that I'm trying to extract the data for every day of June, July, August for the next 79 years. But I'm a novice programmer and I realize there might've been a few oversights by me (efficiency wise) that might've resulted in a slightly better performance.
This is the snippet
def calculateTemp(coords, year, model):
"""
takes in all coordinates of a line between two grid stations and the year
converts the year into date
takes average of temperature of each day of the month of June for each
coordinate and then takes average of all coordinates to find average temp
for that line for the month of June
"""
print(year)
# coords represents a list of different sets of coordinates between two grids
temp3 = 0 # sum of all temps of all coordinates
for i in range(0, len(coords)):
temp2 = 0
counter = 0
# this loop represents that the 15 years data is being extracted for
# each coordinate set and average of those 15 years is being taken
for p in range(0, 15):
temp1 = 0 # sum of all temps for one coordinate in all days of June, tuly, august
if year+ p < 100:
# this loop represents the months of jun, jul, aug
for j in range(6, 9):
# 30 days of each month
for k in range(1, 31):
if k < 10:
# this if-else makes a string of date
date = '20'+str(year+p)+'-0'+str(j)+'-0'+str(k)
else:
date = '20'+str(year+p)+'-0'+str(j)+'-'+str(k)
# there are 3 variants of the climate model
# for years upto 2040, between 2041-2070
# and between 2071 and 2099
# hence this if else block
if year+p < 41:
temp1 += model[0]['tasmax'].sel(
lon=coords[i][1], lat=coords[i][0], time=date, method='nearest').data[0]
elif year+p >= 41 and year+p <71:
temp1 += model[1]['tasmax'].sel(
lon=coords[i][1], lat=coords[i][0], time=date, method='nearest').data[0]
else:
temp1 += model[2]['tasmax'].sel(
lon=coords[i][1], lat=coords[i][0], time=date, method='nearest').data[0]
counter += 1
avg = temp1/(len(range(0,30))*len(range(6,9)))
temp2 += avg
temp3 += temp2/counter
Tamb = temp3/len(coords)
return Tamb
Is there anyway I can increase the performance of this code and optimize it?
I just replaced the innermost loops k in range(1,31)and j in range(6,9)into a dict comprehension to generate all the dates and corresponding value from your model. Then simply averaged these values for every value of p and then for every coord in coords.
Give this a shot. Dicts should make the processing faster. Also check if the averages are exactly how you are calculating them in your function.
def build_date(year,p,j,k):
return '20'+str(year+p)+'-0'+str(j)+'-0'+str(k) if k<10 else '20'+str(year+p)+'-0'+str(j)+'-'+str(k)
def calculateTemp(coords, year, model):
func2 = lambda x,date:model[x]['tasmax'].sel(lon=coords[i][1],
lat=coords[i][0],
time=date,
method='nearest').data[0]
print(year)
out = {}
for i in range(len(coords)):
inner = {}
for p in range(0,15):
if year + p < 100:
dates = {build_date(year,p,j,k):func2(0,build_date(year,p,j,k)) if year+p<41 \
else func2(1,build_date(year,p,j,k)) if (year+p >= 41 and year+p <71) \
else func2(2,build_date(year,p,j,k))
for j in range(6,9) \
for k in range(1,31) }
inner[p] = sum([v for k,v in dates.items()])/len(dates)
out[i] = inner
coord_averages = {k : sum(v.values())/len(v) for k,v in out.items() }
Tamb = sum([v for k,v in coord_averages.items()])/len(coord_averages)
return Tamb
I'm trying to build a function that recieves a date and adds days, updating everything in case it changes, so far i've come up with this:
def addnewDate(date, numberOfDays):
date = date.split(":")
day = int(date[0])
month = int(date[1])
year = int(date[2])
new_days = 0
l = 0
l1 = 28
l2 = 30
l3 = 31
#l's are the accordingly days of the month
while numberOfDays > l:
numberOfDays = numberOfDays - l
if month != 12:
month += 1
else:
month = 1
year += 1
if month in [1, 3, 5, 7, 8, 10, 12]:
l = l3
elif month in [4, 6, 9, 11]:
l = l2
else:
l = l1
return str(day) + ':' + str(month) + ':' + str(year) #i'll deal
#with fact that it doesn't put the 0's in the < 10 digits later
Desired output:
addnewDate('29:12:2016', 5):
'03:01:2017'
I think the problem is with either the variables, or the position i'm using them in, kinda lost though..
Thanks in advance!
p.s I can't use python build in functions :)
Since you cannot use standard library, here's my attempt. I hope I did not forget anything.
define a table for month lengths
tweak it if leap year detected (every 4 year, but special cases)
work on zero-indexed days & months, much easier
add the number of days. If lesser that current month number of days, end, else, substract current month number of days and retry (while loop)
when last month reached, increase year
add 1 to day and month in the end
code:
def addnewDate(date, numberOfDays):
month_days = [31,28,31,30,31,30,31,31,30,31,30,31]
date = date.split(":")
day = int(date[0])-1
month = int(date[1])-1
year = int(date[2])
if year%4==0 and year%400!=0:
month_days[1]+=1
new_days = 0
#l's are the accordingly days of the month
day += numberOfDays
nb_days_month = month_days[month]
done = False # since you don't want to use break, let's create a flag
while not done:
nb_days_month = month_days[month]
if day < nb_days_month:
done = True
else:
day -= nb_days_month
month += 1
if month==12:
year += 1
month = 0
return "{:02}:{:02}:{:04}".format(day+1,month+1,year)
test (may be not exhaustive):
for i in ("28:02:2000","28:02:2004","28:02:2005","31:12:2012","03:02:2015"):
print(addnewDate(i,2))
print(addnewDate(i,31))
result:
02:03:2000
31:03:2000
01:03:2004
30:03:2004
02:03:2005
31:03:2005
02:01:2013
31:01:2013
05:02:2015
06:03:2015
of course, this is just for fun. Else use time or datetime modules!
I have defined a procedure in python which outputs a number, and would like to add the results of calling the procedure on two different inputs. However, when I try to perform arithmetic on the result of a procedure, I am presented with the error message,
TypeError: unsupported operand type(s) for -: 'NoneType' and
'NoneType'.
I tried using the int() function, but apparently this cannot operate on 'NoneType' results. How would I go about adding the two results?
The segment of the code in question is:
def leapYear(year):
if year % 4 != 0:
year = 365
else:
if year % 100 != 0:
year = 366
else:
if year % 400 != 0:
year = 365
else:
year = 366
def daysBetweenDates(year1, month1, day1, year2, month2, day2):
dpY = leapYear(year2) - leapYear(year1)
It's part of my attempted solution for a problem on Udacity (I'm relatively new to coding).
You need to explicitly return the result of the function you wish to use. Therefore, you need to add the following line to the end of your leapYear function:
return year
with a single level of indentation.
Complete example:
def leapYear(year):
if year % 4 != 0:
year = 365
else:
if year % 100 != 0:
year = 366
else:
if year % 400 != 0:
year = 365
else:
year = 366
return year
def daysBetweenDates(year1, month1, day1, year2, month2, day2):
return leapYear(year2) - leapYear(year1)
If a value is not returned explicitly, a Python function returns a None value.
That being said, you can make your life easier by using the datetime module, and in particular the datetime.timedelta objects.
You forgot to return year in leapYear() procedure, by default it will return None.
Use this:
def leapYear(year):
if year % 4 != 0:
year = 365
else:
if year % 100 != 0:
year = 366
else:
if year % 400 != 0:
year = 365
else:
year = 366
return year
def daysBetweenDates(year1, month1, day1, year2, month2, day2):
dpY = leapYear(year2) - leapYear(year1)
So here is the structure of my defaultdict
#x = {lead_id:[[month,pid,year]]
x={'123':[[1,9,2015],[2,9,2015]],'345':[[2,10,2015],[2,13,2014]],'159':[1,3,2015].....}
I have more than 1000 lead_id's in this dictionary. Each one has random number of lists.In the other words, that same lead_id has duplicates but with different month or pid or year. Now i want to count all the lead_id's in January 2015.I want to count it as two if its two times or more than that according to its occurrence . Can anyone please help me to figure out how i can make an automated code so that it will check the length as well as the number of times that month with same year occurred.
For example:
x={'123':[[1,3,2015],[2,5,2014],[1,5,2015]],'987':[[3,55,2014]],'456':[[1,37,2015]]}
count of jan 2015 = 3
You can use this also...
sum(1 for i in x for j in x[i] if j[0] == 1 and j[2] == 2015)
You can do conditionals on the index values. date[0] is 1 for Jan. date[2] is 2015
#!/usr/bin/python
x={'123':[[1,3,2015],[2,5,2014],[1,5,2015]],'987':[[3,55,2014]],'456':[[1,37,2015]]}
#Set query dates
query_month = 1 #jan
query_year = 2015 #year
#Set a counter
jan_counts = 0
for list_of_dates in x.values():
for date in list_of_dates:
if (date[0] == query_month) and (date[2] == query_year):
jan_counts += 1
print jan_counts
#3
This should give your result:
>>> day = 1
>>> year = 2015
>>> x = {'123':[[1,3,2015],[2,5,2014],[1,5,2015]],'987':[[3,55,2014]],'456':[[1,37,2015]]}
>>> sum([1 for k, v in x.iteritems() for i in v if i[0] == day and i[2] == year])
3
I'm having a very hard time troubleshooting my code. All I'm trying to do is have the user enter in a starting and an ending year, and then be able to calculate all the leap years in between. I'm still very new to Python, and just can't figure out why my while loop isn't doing what I want it to do.
starting = int(raw_input('Enter starting year: '))
ending = int(raw_input('Enter ending year: '))
print 'Leap years between', starting, 'and', ending
while starting <= ending:
if starting % 4 == 0 and starting % 100 != 0:
print starting
if starting % 100 == 0 and starting % 400 == 0:
print starting
starting = starting + 1
That is what I have right now. I really would prefer not to have the answer just given to me, but if I could get a little hint as to why my while loop isn't working I would really appreciate it.
This is the output I see in my IDE:
The code is working just fine. This was the following session:
Enter starting year: 2008
Enter ending year: 2032
Leap years between 2008 and 2032
2008
2012
2016
2020
2024
2028
2032
That corresponds perfectly with the information give here.
Console session:
>>> from leapyear import leap
>>> leap()
Enter starting year: >? 2008
Enter ending year: >? 2032
Leap years between 2008 and 2032
2008
2012
2016
2020
2024
2028
2032
leapyear.py
def leap():
starting = int(raw_input('Enter starting year: '))
ending = int(raw_input('Enter ending year: '))
print 'Leap years between', starting, 'and', ending
while starting <= ending:
if starting % 4 == 0 and starting % 100 != 0:
print(starting)
if starting % 100 == 0 and starting % 400 == 0:
print(starting)
starting += 1
You can also do this function using list comprehensions:
def new_leap(start, end):
return [x for x in xrange(start, end + 1)
if (x % 400 == 0) or (x % 4 == 0 and not x % 100 == 0)]
Console session:
>>> from leapyear import new_leap
>>> new_leap(2008, 2032)
[2008, 2012, 2016, 2020, 2024, 2028, 2032]
I think this will contain all the Test Case
We have added all the invalid cases in value=c
and just matched and removed the value from b
def is_leap(year):
leap = False
leap1=True
b=[]
for a in range(1800,year+200,4):
b.append(a)
c=[1800,1900,2100,2200,2300,2500,2600,2700,2800,2900]
for d in range(len(c)):
e=c[d]
if e in b:
b.remove(e)
if year in b:
return leap1
else:
return leap
year = int(input())
print(is_leap(year))
def is_leap(year):
leap = False
if year%4 ==0 :
leap = True
elif year%100 ==0:
leap = False
elif year%400 ==0:
leap = True
return leap
year = int(raw_input())
print is_leap(year)
startingYear = eval(input("Enter starting year:")
endingYear = eval(input("Enter ending year:")
for year in range(startingYear, endingYear + 1):
if (year % 4 == 0 and year % 100 != 0) or (year % 400 == 0):
print(year)