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If your computer doesn't recognize your connected device, you might see an unknown error or a '0xE' error. If you do, follow these steps and try to connect your device again after each step:
- Make sure that your iOS or iPadOS device is unlocked and on the Home screen.
- Check that you have the latest software on your Mac or Windows PC. If you're using iTunes, make sure you have the latest version.
- Make sure that your device is turned on.
- If you see a Trust this Computer alert, unlock your device and tap Trust.
- Unplug all USB accessories from your computer except for your device. Try each USB port to see if one works. Then try a different Apple USB cable.*
- Restart your computer.
- Restart your device:
- Try connecting your device to another computer. If you have the same issue on another computer, contact Apple Support.
For more help, follow the steps below for your Mac or Windows PC.
* Learn how to connect iPad Pro (11-inch) or iPad Pro 12.9-inch (3rd generation) to your computer.
If you use a Mac
- Connect your iOS or iPadOS device and make sure that it's unlocked and on the Home screen.
- On your Mac, hold down the Option key, click the Apple menu, and choose System Information or System Report.
- From the list on the left, select USB.
- If you see your iPhone, iPad, or iPod under USB Device Tree, get the latest macOS or install the latest updates. If you don't see your device or still need help, contact Apple Support.
If you use a Windows PC
The steps differ depending on if you downloaded iTunes from the Microsoft Store or from Apple.
If you downloaded iTunes from the Microsoft Store
Follow these steps to reinstall the Apple Mobile Device USB driver:
- Disconnect your device from your computer.
- Unlock your iOS or iPadOS device and go to the Home screen. Then reconnect your device. If iTunes opens, close it.
- Click and hold (or right-click) the Start button, then choose Device Manager.
- Locate and expand the Portable Devices section.
- Look for your connected device (such as Apple iPhone), then right-click on the device name and choose Update driver.
- Select 'Search automatically for updated driver software.'
- After the software installs, go to Settings > Update & Security > Windows Update and verify that no other updates are available.
- Open iTunes.
If you downloaded iTunes from Apple
Follow these steps to reinstall the Apple Mobile Device USB driver:
- Disconnect your device from your computer.
- Unlock your iOS or iPadOS device and go to the Home screen. Then reconnect your device. If iTunes opens, close it.
- Press the Windows and R key on your keyboard to open the Run command.
- In the Run window, enter:
%ProgramFiles%Common FilesAppleMobile Device SupportDrivers
- Click OK.
- Right-click on the
usbaapl64.inf
orusbaapl.inf
file and choose Install.
You might see other files that start withusbaapl64
orusbaapl
. Make sure to install the file that ends in .inf. If you’re not sure which file to install, right-click a blank area in the File Explorer Window, click View, then click Details to find the correct file type. You want to install the Setup Information file. - Disconnect your device from your computer, then restart your computer.
- Reconnect your device and open iTunes.
If your device still isn't recognized
Check Device Manager to see if the Apple Mobile Device USB driver is installed. Follow these steps to open Device Manager:
- Press the Windows and R key on your keyboard to open the Run command.
- In the Run window, enter
devmgmt.msc
, then click OK. Device Manager should open. - Locate and expand the Universal Serial Bus controllers section.
- Look for the Apple Mobile Device USB driver.
If you don't see the Apple Mobile Device USB Driver or you see Unknown Device:
- Connect your device to your computer with a different USB cable.
- Connect your device to a different computer. If you have the same issue on another computer, contact Apple Support.
If you see the Apple Mobile Device USB driver with an error symbol:
If you see , , or next to the Apple Mobile Device USB driver, follow these steps:
- Restart the Apple Mobile Device Service.
- Check for and resolve issues with third-party security software, then restart your computer.
- Try to install the
usbaapl64.inf
orusbaapl.inf
file again.
I want to draw arrows in a log-log plot that have different lengths but should have a similar-looking head. The head width is indeed the same, but the length of the head seems to scale with the arrow length. How can I get the short-looking head of the right-pointing arrow to look like the other head?
You can adjust the head and connection style in the arrowprops
like this (for the full set of options see the matplotlib docs:
Then to adjust the width of your arrow use the size
paramater in annotate
:
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...
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]] ...
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...
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://**:****@127.0.0.1:1433/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 =...
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...
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...
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...
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...
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...
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
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 #...
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...
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...
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...
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...
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!...
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...
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...
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...
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...
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...
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 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') ...
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 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...
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,...
Django: html without CSS and the right text
python,html,css,django,url
Are you using the {% load staticfiles %} in your templates?
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> <div> {% 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...
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...
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....
REGEX python find previous string
python,regex,string
Arrow Log Laptops App
Updated: This will check for the existence of a sentence followed by special characters. It returns false if there are no special characters, and your original sentence is in capture group 1. Updated Regex101 Example r'(.*[w])([^w]+)' Alternatively (without a second capture group): Regex101 Example - no second capture group r'(.*[w])(?:[^w]+)'...
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)...
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)...
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...
Python: can't access newly defined environment variables
python,bash,environment-variables
Arrow Log Laptops Amazon
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,...
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.
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. ...
Arrow Log Laptops For Windows 7
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...
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 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...
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....
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....
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....
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...
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...
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....
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:Pythontest.py', line 14 print 'hello' ^ SyntaxError: invalid syntax When clearly the error is...
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 ...
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):...
