Menu
  • HOME
  • TAGS

Selecting Data from Last Week in Python

Tag: python,datetime,pandas,format,dataframes

I have a large database and I am looking to read only the last week for my python code.

My first problem is that the column with the received date and time is not in the format for datetime in pandas. My input (Column 15) looks like this:

recvd_dttm
1/1/2015 5:18:32 AM
1/1/2015 6:48:23 AM
1/1/2015 13:49:12 PM

From the Time Series / Date functionality in the pandas library I am looking at basing my code off of the "Week()" function shown in the example below:

In [87]: d
Out[87]: datetime.datetime(2008, 8, 18, 9, 0)

In [88]: d - Week()
Out[88]: Timestamp('2008-08-11 09:00:00')

I have tried ordering the date this way:

df =pd.read_csv('MYDATA.csv')
orderdate = datetime.datetime.strptime(df['recvd_dttm'], '%m/%d/%Y').strftime('%Y %m %d')

however I am getting this error 

TypeError: must be string, not Series

Does anyone know a simpler way to do this, or how to fix this error?

Edit: The dates are not necessarily in order. AND sometimes there is a faulty error in the database like a date that is 9/03/2015 (in the future) someone mistyped. I need to be able to ignore those.

Best How To :

import datetime as dt

# convert strings to datetimes
df['recvd_dttm'] = pd.to_datetime(df['recvd_dttm'])

# get first and last datetime for final week of data
range_max = df['recvd_dttm'].max()
range_min = range_max - dt.timedelta(days=7)

# take slice with final week of data
sliced_df = df[(df['recvd_dttm'] >= range_min) & 
               (df['recvd_dttm'] <= range_max)]

SQLAlchemy. 2 different relationships for 1 column

python,sqlalchemy

I'm afraid you can't do it like this. I suggest you have just one relationship users and validate the insert queries.

How does the class_weight parameter in scikit-learn work?

python,scikit-learn

First off, it might not be good to just go by recall alone. You can simply achieve a recall of 100% by classifying everything as the positive class. I usually suggest using AUC for selecting parameters, and then finding a threshold for the operating point (say a given precision level)...

Sort when values are None or empty strings python

python,list,sorting,null

If you want the None and '' values to appear last, you can have your key function return a tuple, so the list is sorted by the natural order of that tuple. The tuple has the form (is_none, is_empty, value); this way, the tuple for a None value will be...

How to remove structure with python from this case?

python,python-2.7

It's complicated to use regex, a stupid way I suggested: def remove_table(s): left_index = s.find('<table>') if -1 == left_index: return s right_index = s.find('</table>', left_index) return s[:left_index] + remove_table(s[right_index + 8:]) There may be some blank lines inside the result....

In sklearn, does a fitted pipeline reapply every transform?

python,scikit-learn,pipeline,feature-selection

The pipeline calls transform on the preprocessing and feature selection steps if you call pl.predict. That means that the features selected in training will be selected from the test data (the only thing that makes sense here). It is unclear what you mean by "apply" here. Nothing new will be...

How do variables inside python modules work?

python,module,python-module

The convention is to declare constants in modules as variables written in upper-case (Python style guide: https://www.python.org/dev/peps/pep-0008/#global-variable-names). But there's no way to prevent someone else to re-declare such a variable -- thus ignoring conventions -- when importing a module. There are two ways of working around this when importing modules...

Displaying a 32-bit image with NaN values (ImageJ)

python,image-processing,imagej

The display range of your image might not be set correctly. Try outputImp.resetDisplayRange() or outputImp.setDisplayRange(Stats.min, Stats.max) See the ImagePlus javadoc for more info....

Python recursive function not recursing

python,recursion

Afraid I don't know much about python, but I can probably help you with the algorithm. The encoding process repeats the following: multiply the current total by 17 add a value (a = 1, b = 2, ..., z = 26) for the next letter to the total So at...

Identify that a string could be a datetime object

python,regex,algorithm,python-2.7,datetime

What about fuzzyparsers: Sample inputs: jan 12, 2003 jan 5 2004-3-5 +34 -- 34 days in the future (relative to todays date) -4 -- 4 days in the past (relative to todays date) Example usage: >>> from fuzzyparsers import parse_date >>> parse_date('jun 17 2010') # my youngest son's birthday datetime.date(2010,...

Is timezone info redundant provided that UTC timestamp is available?

datetime,time,timezone,timestamp,timestamp-with-timezone

For a single event, knowing the UTC instant on which it occurs is usually enough, so long as you have the right UTC instant (see later). For repeated events, you need to know the time zone in which it repeats... not just the UTC offset, but the actual time zone....

how to enable a entry by clicking a button in Tkinter?

python,tkinter

You need to use the configure method of each widget: def rakhi(): entry1.configure(state="normal") entry2.configure(state="normal") ...

odoo v8 - Field(s) `arch` failed against a constraint: Invalid view definition

python,xml,view,odoo,add-on

You have made silly mistake in defining _columns. _colums is not valid dictionary name for fields structure. Replace this by _columns and restart service and update module. ...

Create an exe with Python 3.4 using cx_Freeze

python,python-3.4,cx-freeze

Since you want to convert python script to exe have a look at py2exe

Matplotlib: Plot the result of an SQL query

python,sql,matplotlib,plot

Take this for a starter code : import numpy as np import matplotlib.pyplot as plt from sqlalchemy import create_engine import _mssql fig = plt.figure() ax = fig.add_subplot(111) engine = create_engine('mssql+pymssql://**:[email protected]:1433/AffectV_Test') connection = engine.connect() result = connection.execute('SELECT Campaign_id, SUM(Count) AS Total_Count FROM Impressions GROUP BY Campaign_id') ## the data data =...

Django: html without CSS and the right text

python,html,css,django,url

Are you using the {% load staticfiles %} in your templates?

Spring-integration scripting with Python

python,spring-integration,jython

This is a bug in Spring Integration; I have opened a JIRA Issue. if (variables != null) { result = scriptEngine.eval(script, new SimpleBindings(variables)); } else { result = scriptEngine.eval(script); } When the first branch of the if test is taken, the result variable is added to the SimpleBindings object, and...

Parse text from a .txt file using csv module

python,python-2.7,parsing,csv

How about using Regular Expression def get_info(string_to_search): res_dict = {} import re find_type = re.compile("Type:[\s]*[\w]*") res = find_type.search(string_to_search) res_dict["Type"] = res.group(0).split(":")[1].strip() find_Status = re.compile("Status:[\s]*[\w]*") res = find_Status.search(string_to_search) res_dict["Status"] = res.group(0).split(":")[1].strip() find_date = re.compile("Date:[\s]*[/0-9]*") res = find_date.search(string_to_search) res_dict["Date"] = res.group(0).split(":")[1].strip() res_dict["description"] =...

How to use template within Django template?

python,html,django,templates,django-1.4

You can use the include tag in order to supply the included template with a consistent variable name: For example: parent.html <div class="row"> <div class="col-md-12 col-lg-12 block block-color-1"> {% include 'templates/child.html' with list_item=mylist.0 t=50 only %} </div> </div> child.html {{ list_item.text|truncatewords:t }} UPDATE: As spectras recommended, you can use the...

Inconsistency between gaussian_kde and density integral sum

python,numpy,kernel-density

As stated in my comment, this is an issue with kernel density support. The Gaussian kernel has infinite support. Even fit on data with a specific range the range of the Gaussian kernel will be from negative to positive infinity. That being said the large majority of the density will...

sys.argv in a windows environment

python,windows,python-3.x

You are calling the script wrong Bring up a cmd (command line prompt) and type: cd C:/Users/user/PycharmProjects/helloWorld/ module_using_sys.py we are arguments And you will get the correct output....

Strange Behavior: Floating Point Error after Appending to List

python,python-2.7,behavior

Short answer: your correct doesn't work. Long answer: The binary floating-point formats in ubiquitous use in modern computers and programming languages cannot represent most numbers like 0.1, just like no terminating decimal representation can represent 1/3. Instead, when you write 0.1 in your source code, Python automatically translates this to...

Peewee: reducing where conditionals break after a certain length

python,peewee

Try ...where(SomeTable.BIN.in_(big_list)) PeeWee has restrictions as to what can be used in their where clause in order to work with the library. http://docs.peewee-orm.com/en/latest/peewee/querying.html#query-operators...

How to check for multiple attributes in a list

python,python-2.7

You can create a set holding the different IDs and then compare the size of that set to the total number of quests. The difference tells you how many IDs are duplicated. Same for names. Something like this (untested): def test_quests(quests): num_total = len(quests) different_ids = len(set((q.ID for q in...

Pandas - Dropping multiple empty columns

python,pandas

You can just subscript the columns: df = df[df.columns[:11]] This will return just the first 11 columns or you can do: df.drop(df.columns[11:], axis=1) To drop all the columns after the 11th one....

How do I read this list and parse it?

python,list

Your list contains one dictionary you can access the data inside like this : >>> yourlist[0]["popularity"] 2354 [0] for the first item in the list (the dictionary). ["popularity"] to get the value associated to the key 'popularity' in the dictionary....

Using counter on array for one value while keeping index of other values

python,collections

To count how often one value occurs and at the same time you want to select those values, you'd simply select those values and count how many you selected: fruits = [f for f in foods if f[0] == 'fruit'] fruit_count = len(fruits) If you need to do this for...

SyntaxError: invalid syntax?

python,syntax

Check the code before the print line for errors. This can be caused by an error in a previous line; for example: def x(): y = [ print "hello" x() This produces the following error: File "E:\Python\test.py", line 14 print "hello" ^ SyntaxError: invalid syntax When clearly the error is...

Python - Opening and changing large text files

python,replace,out-of-memory,large-files

You need to read one bite per iteration, analyze it and then write to another file or to sys.stdout. Try this code: mesh = open("file.mesh", "r") mesh_out = open("file-1.mesh", "w") c = mesh.read(1) if c: mesh_out.write("{") else: exit(0) while True: c = mesh.read(1) if c == "": break if c...

Pandas Dataframe Complex Calculation

python,python-2.7,pandas,dataframes

I believe the following does what you want: In [24]: df['New_Col'] = df['ActualCitations']/pd.rolling_sum(df['totalPubs'].shift(), window=2) df Out[24]: Year totalPubs ActualCitations New_Col 0 1994 71 191.002034 NaN 1 1995 77 2763.911781 NaN 2 1996 69 2022.374474 13.664692 3 1997 78 3393.094951 23.240376 So the above uses rolling_sum and shift to generate the...

group indices of list in list of lists

python,list

Use collections.OrderedDict: from collections import OrderedDict od = OrderedDict() lst = [2, 0, 1, 1, 3, 2, 1, 2] for i, x in enumerate(lst): od.setdefault(x, []).append(i) ... >>> od.values() [[0, 5, 7], [1], [2, 3, 6], [4]] ...

Replace nodejs for python?

python,node.js,webserver

You might want to have a look at Tornado. It is well-documented and features built-in support for WebSockets. If you want to steer clear of the Tornado-framework, there are several Python implementations of Socket.io. Good luck!...

Twilio Client Python not Working in IOS Browser

javascript,python,ios,flask,twilio

Twilio developer evangelist here. Twilio Client uses WebRTC and falls back to Flash in order to make web browsers into phones. Unfortunately Safari on iOS supports neither WebRTC nor Flash so Twilio Client cannot work within any browser on iOS. It is possible to build an iOS application to use...

Count function counting only last line of my list

python,python-2.7

I don't know what you are exactly trying to achieve but if you are trying to count R and K in the string there are more elegant ways to achieve it. But for your reference I had modified your code. N = int(raw_input()) s = [] for i in range(N):...

Find the tf-idf score of specific words in documents using sklearn

python,scikit-learn,tf-idf

Yes. See .vocabulary_ on your fitted/transformed TF-IDF vectorizer. In [1]: from sklearn.datasets import fetch_20newsgroups In [2]: data = fetch_20newsgroups(categories=['rec.autos']) In [3]: from sklearn.feature_extraction.text import TfidfVectorizer In [4]: cv = TfidfVectorizer() In [5]: X = cv.fit_transform(data.data) In [6]: cv.vocabulary_ It is a dictionary of the form: {word : column index in...

Can't get value from xpath python

python,html,xpath,web-scraping,html-parsing

The values in the table are generated with the help of javascript being executed in the browser. One option to approach it is to automate a browser via selenium, e.g. a headless PhantomJS: >>> from selenium import webdriver >>> >>> driver = webdriver.PhantomJS() >>> driver.get("http://www.tabele-kalorii.pl/kalorie,Actimel-cytryna-miod-Danone.html") >>> >>> table = driver.find_element_by_xpath(u"//table[tbody/tr/td/h3...

Python: can't access newly defined environment variables

python,bash,environment-variables

After updating your .bashrc, perform source ~/.bashrc to apply the changes. Also, merge the two BONSAI-related calls into one: export BONSAI=/home/me/Utils/bonsai_v3.2 UPDATE: It was actually an attempt to update the environment for some Eclipse-based IDE. This is a different usecase altogether. It should be described in the Eclipse help. Also,...

ctypes error AttributeError symbol not found, OS X 10.7.5

python,c++,ctypes

Your first problem is C++ name mangling. If you run nm on your .so file you will get something like this: nm test.so 0000000000000f40 T __Z3funv U _printf U dyld_stub_binder If you mark it as C style when compiled with C++: #ifdef __cplusplus extern "C" char fun() #else char fun(void)...

MySQLdb Python - Still getting error when using CREATE TABLE IF NOT EXISTS

python,mysql

MySQL is actually throwing a warning rather that an error. You can suppress mysql warnings like this : import MySQLdb as mdb from warnings import filterwarnings filterwarnings('ignore', category = mdb.Warning) Now the mysql warnings will be gone. But mysql errors will be shown as usual Read more about warnings at...

Python: histogram/ binning data from 2 arrays.

python,histogram,large-files

if you only need to do this for a handful of points, you could do something like this. If intensites and radius are numpy arrays of your data: bin_width = 0.1 # Depending on how narrow you want your bins def get_avg(rad): average_intensity = intensities[(radius>=rad-bin_width/2.) & (radius<rad+bin_width/2.)].mean() return average_intensities #...

represent an index inside a list as x,y in python

python,list,numpy,multidimensional-array

According to documentation of numpy.reshape , it returns a new array object with the new shape specified by the parameters (given that, with the new shape, the amount of elements in the array remain unchanged) , without changing the shape of the original object, so when you are calling the...

How to change the IP address of Amazon EC2 instance using boto library

python,amazon-web-services,boto

Make sure you have set properly with ~/.boto and connect to aws, have the boto module ready in python. If not, go through this first: Getting Started with Boto For example, you need assign a new EIP 54.12.23.34 to the instance i-12345678 Make sure, EIP has been allocated(existed) and you...

How to put an image on another image in python, using ImageTk?

python,user-interface,tkinter

Just use photoshop or G.I.M.P.. I assure you, doing it that way will be much simpler and less redundant than essentially getting Tkinter to photo edit for you (not to mention what you're talking about is just bad practice when it comes to coding) Anyways, I guess if you really...

The event loop is already running

python,python-3.x,pyqt,pyqt4

I think the problem is with your start.py file. You have a function refreshgui which re imports start.py import will run every part of the code in the file. It is customary to wrap the main functionality in an ''if __name__ == '__main__': to prevent code from being run on...

Python np.delete issue

python,numpy

Don't call np.delete in a loop. It would be quicker to use boolean indexing: In [6]: A[X.astype(bool).any(axis=0)] Out[6]: array([[3, 4, 5]]) X.astype(bool) turns 0 into False and any non-zero value into True: In [9]: X.astype(bool).any(axis=0) Out[9]: array([False, True, False], dtype=bool) the call to .any(axis=0) returns True if any value in...

Inserting a variable in MongoDB specifying _id field

python,mongodb,pymongo

Insert only accepts a final document or an array of documents, and an optional object which contains additional options for the collection. db.collection.insert( <document or array of documents>, { // options writeConcern: <document>, ordered: <boolean> } ) You may want to add the _id to the document in advance, but...

trying to understand LSH through the sample python code

python,similarity,locality-sensitive-hash

a. It's a left shift: https://docs.python.org/2/reference/expressions.html#shifting-operations It shifts the bits one to the left. b. Note that ^ is not the "to the power of" but "bitwise XOR" in Python. c. As the comment states: it defines "number of bits per signature" as 2**10 → 1024 d. The lines calculate...

Calling function and passing arguments multiple times

python,function,loops

a,b,c = 1,2,3 while i<n: a,b,c = myfunction(a,b,c) i +=1 ...

Python Popen - wait vs communicate vs CalledProcessError

python,python-2.7,error-handling,popen

about the deadlock: It is safe to use stdout=PIPE and wait() together iff you read from the pipe. .communicate() does the reading and calls wait() for you about the memory: if the output can be unlimited then you should not use .communicate() that accumulates all output in memory. what...

Sum of two variables in RobotFramework

python,automated-tests,robotframework

By default variables are string in Robot. So your first two statements are assigning strings like "xx,yy" to your vars. Then "evaluate" just execute your statement as Python would do. So, adding your two strings with commas will produce a list: $ python >>> 1,2+3,4 (1, 5, 4) So you...