How to convert "2011-2012" to datetime object in mongodb in python? - python-3.x

Hi I am saving year as string as "2011-2012" in db, i want to convert it to datetime object and save it in datetime object like "datetime.datetime(2011, 1, 1, 0, 0)-datetime.datetime(2012, 1, 1, 0, 0)"?
can you please help me


you could use rrule from the dateutil package:
from datetime import datetime
from dateutil.rrule import rrule, MONTHLY
# input string:
years = '2011-2012'
# map to integer:
years = tuple(map(int, years.split('-')))
# obtain a datetime object for the starting year and the total years:
start_year = datetime(years[0], 1, 1)
total_years = years[1]-years[0]
# use rrule to generate a monthly range:
monthrange = []
dt_range = list(rrule(freq=MONTHLY, count=total_years*12+1, dtstart=start_year))
# [datetime.datetime(2011, 1, 1, 0, 0),
# datetime.datetime(2011, 2, 1, 0, 0),
# datetime.datetime(2011, 3, 1, 0, 0),
# datetime.datetime(2011, 4, 1, 0, 0),
# datetime.datetime(2011, 5, 1, 0, 0),
# datetime.datetime(2011, 6, 1, 0, 0),
# datetime.datetime(2011, 7, 1, 0, 0),
# datetime.datetime(2011, 8, 1, 0, 0),
# datetime.datetime(2011, 9, 1, 0, 0),
# datetime.datetime(2011, 10, 1, 0, 0),
# datetime.datetime(2011, 11, 1, 0, 0),
# datetime.datetime(2011, 12, 1, 0, 0),
# datetime.datetime(2012, 1, 1, 0, 0)]

Related

Compare two lists of lists and fill in blank values

I'm reading data from an API and have a list of lists like this:
listData = [[datetime.datetime(2018, 1, 1, 5, 0), -6.78125],
[datetime.datetime(2018, 1, 1, 7, 0), -6.125],
[datetime.datetime(2018, 1, 1, 8, 0), -5.90625]]
I need to create a complete list filling in the missing values. I've created a destination, like this:
listDest = [[datetime.datetime(2018, 1, 1, 5, 0), None],
[datetime.datetime(2018, 1, 1, 6, 0), None],
[datetime.datetime(2018, 1, 1, 7, 0), None],
[datetime.datetime(2018, 1, 1, 8, 0), None]]
The end result should look like this:
[[datetime.datetime(2018, 1, 1, 5, 0), -6.78125],
[datetime.datetime(2018, 1, 1, 6, 0), None],
[datetime.datetime(2018, 1, 1, 7, 0), -6.125],
[datetime.datetime(2018, 1, 1, 8, 0), -5.90625]]
Here is the code I've tried:
for blankTime, blankValue in listDest:
for dataTime, dataValue in listData:
if blankTime == dataTime:
blankIndex = listDest.index(blankTime)
dataIndex = listData.index(dataTime)
listDest[blankIndex] = tempRm7[dataIndex]
This returns the following error, which is confusing since I know that value is in both lists.
ValueError: datetime.datetime(2018, 1, 1, 5, 0) is not in list
I attempted to adapt the methods in this answer but that's for a 1D list and I couldn't figure out how to make it work for my 2D list.

If both lists are sorted, you can merge them and then group them (using heapq.merge/itertools.groupby):
import datetime
from heapq import merge
from itertools import groupby
listData = [[datetime.datetime(2018, 1, 1, 5, 0), -6.78125],
[datetime.datetime(2018, 1, 1, 7, 0), -6.125],
[datetime.datetime(2018, 1, 1, 8, 0), -5.90625]]
listDest = [[datetime.datetime(2018, 1, 1, 5, 0), None],
[datetime.datetime(2018, 1, 1, 6, 0), None],
[datetime.datetime(2018, 1, 1, 7, 0), None],
[datetime.datetime(2018, 1, 1, 8, 0), None]]
out = [next(g) for _, g in groupby(merge(listData, listDest, key=lambda k: k[0]), lambda k: k[0])]
# pretty print to screen:
from pprint import pprint
pprint(out)
Prints:
[[datetime.datetime(2018, 1, 1, 5, 0), -6.78125],
[datetime.datetime(2018, 1, 1, 6, 0), None],
[datetime.datetime(2018, 1, 1, 7, 0), -6.125],
[datetime.datetime(2018, 1, 1, 8, 0), -5.90625]]

Creating a function for my code with datetime and timedelta

I have finished my code and it works when I run it. However, I need to turn this into a function, that if I call the function and pass in any list of number, i can get the same results. This is my code:
from datetime import datetime, timedelta
dateStr = 'user-input'
dateObj = datetime.strptime(dateStr, '%Y%m%d')
timeStep = timedelta(days=1)
dateObj2 = dateObj + timeStep
days15 = [dateObj + timeStep*i for i in range(15)]
print(days15)
------------------ output:
datetime.datetime(2017, 1, 1, 0, 0),..
I need to be able to pass in
date_str = "20170817"
results = days_15(date_str)
print(results)
And then get the same results. Any hints? or any help - Thank you

You just need to add a def statement before your code to define the function, and rather than printing the result, return it:
from datetime import datetime, timedelta
def days_15(dateStr):
dateObj = datetime.strptime(dateStr, '%Y%m%d')
timeStep = timedelta(days=1)
return [dateObj + timeStep*i for i in range(15)]
my_date_str = "20170817"
results = days_15(my_date_str)
print(results)
Output:
[
datetime.datetime(2017, 8, 17, 0, 0), datetime.datetime(2017, 8, 18, 0, 0),
datetime.datetime(2017, 8, 19, 0, 0), datetime.datetime(2017, 8, 20, 0, 0),
datetime.datetime(2017, 8, 21, 0, 0), datetime.datetime(2017, 8, 22, 0, 0),
datetime.datetime(2017, 8, 23, 0, 0), datetime.datetime(2017, 8, 24, 0, 0),
datetime.datetime(2017, 8, 25, 0, 0), datetime.datetime(2017, 8, 26, 0, 0),
datetime.datetime(2017, 8, 27, 0, 0), datetime.datetime(2017, 8, 28, 0, 0),
datetime.datetime(2017, 8, 29, 0, 0), datetime.datetime(2017, 8, 30, 0, 0),
datetime.datetime(2017, 8, 31, 0, 0)
]

Python: Converting Binary to Decimal

What I'm currently doing is a implementation of Genetic Algorithms. I have written my Crossover and mutation methods and now i'm currently writing my Fitness method.
I need to convert my list of 0s and 1s to decimal values for calculating distance.
My current output that I'm working with are a list of integer values of 1s and 0s. (Example below):
[[0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1], [0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1]]
<class 'list'>
I want to convert these numbers to their respected binary equivalent.
I have tried converting the list to groups of 4 and then calling a binaryToDecimal function to convert the bits to decimal values. However, Im getting an error 'TypeError: 'numpy.ndarray' object is not callable'.
I have summarized my code and this is what it looks like so far.
def converting_binary_to_decimal(L):
output = []
for l in L:
l = list(map(str, l))
sub_output = []
for j in range(0, len(l)-1, 4):
sub_output.append(int(''.join(l[j:j+4]), 2))
output.append(sub_output)
return output
def chunks(L, n):
for i in range(0, len(L), n):
yield L[i:i+n]
def fitness(child):
newList1=list(chunks(child[0], 4))
newList2=list(chunks(child[1], 4))
if __name__ == "__main__":
myFitness = fitness(afterMU)
A sample output of what i want is:
[[0, 13, 6, 8, 12, 8, 10, 9, 15], [0, 8, 7, 0, 4, 4, 1, 8, 15]]

Try this code.
def converting_binary_to_decimal(L):
output = []
for l in L:
l = list(map(str, l))
sub_output = []
for j in range(0, len(l)-1, 4):
sub_output.append(int(''.join(l[j:j+4]), 2))
output.append(sub_output)
return output
L = [[0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1], [0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1]]
converting_binary_to_decimal(L)

I think i figured it out.
x=[0, 1, 1, 0]
k = 4
n = len(x)//k
for i in range(n):
y = x[i*k:(i+1)*k]
y = [str(j) for j in y]
y = ''.join(y)
y = int(y,2)
print(y)
Thank you.

numpy packbits pack to uint16 array

I´ve got a 3D numpy bit array, I need to pack them along the third axis. So exactly what numpy.packbits does. But unfortunately it packs it only to uint8, but I need more data, is there a similar way to pack it to uint16 or uint32?

Depending on your machine's endianness it is either a matter of simple view casting or of byte swapping and then view casting:
>>> a = np.random.randint(0, 2, (4, 16))
>>> a
array([[1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0],
[0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1],
[0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1],
[1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1]])
>>> np.packbits(a.reshape(-1, 2, 8)[:, ::-1]).view(np.uint16)
array([53226, 23751, 25853, 64619], dtype=uint16)
# check:
>>> [bin(x + (1<<16))[-16:] for x in _]
['1100111111101010', '0101110011000111', '0110010011111101', '1111110001101011']
You may have to reshape in the end.

Conversion of numpy 2d array to ENVI binary file through gdal

I have SAR CEOS format files which consist of data file, leader file, null volume directory file and volume directory file.
I am reading the data file using gdal ReadAsArray and then I am doing operations on this 2d Array and now I want to save this 2d array as an ENVI binary file.
Kindly guide how to do this in Python 3.5.

Find help for Tutorial Website: https://pcjericks.github.io/py-gdalogr-cookbook/
Such as the example of
import gdal, ogr, os, osr
import numpy as np
def array2raster(newRasterfn,rasterOrigin,pixelWidth,pixelHeight,array):
cols = array.shape[1]
rows = array.shape[0]
originX = rasterOrigin[0]
originY = rasterOrigin[1]
driver = gdal.GetDriverByName('ENVI')
outRaster = driver.Create(newRasterfn, cols, rows, 1, gdal.GDT_Byte)
outRaster.SetGeoTransform((originX, pixelWidth, 0, originY, 0, pixelHeight))
outband = outRaster.GetRasterBand(1)
outband.WriteArray(array)
outRasterSRS = osr.SpatialReference()
outRasterSRS.ImportFromEPSG(4326)
outRaster.SetProjection(outRasterSRS.ExportToWkt())
outband.FlushCache()
def main(newRasterfn,rasterOrigin,pixelWidth,pixelHeight,array):
reversed_arr = array[::-1] # reverse array so the tif looks like the array
array2raster(newRasterfn,rasterOrigin,pixelWidth,pixelHeight,reversed_arr) # convert array to raster
if __name__ == "__main__":
rasterOrigin = (-123.25745,45.43013)
pixelWidth = 10
pixelHeight = 10
newRasterfn = 'test.tif'
array = np.array([[ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
[ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
[ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1],
[ 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1],
[ 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1],
[ 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1],
[ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1],
[ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
[ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
[ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]])
main(newRasterfn,rasterOrigin,pixelWidth,pixelHeight,array)

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