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What's the u prefix in a Python string?
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Combining unicode + raw (regex) strings (e.g. ur"string") is valid in Python 2, but it is unfortunately invalid syntax in Python 3.
– cowlinator
Feb 18 at 9:07
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How do I delete rows in a data frame?
...s that you wanted to delete. However, at some later point, you go into the raw data and have a look around and reorder the data. Your row deletion code will now delete the wrong rows, and worse, you are unlikely to get any errors warning you that this has occurred.
Better strategy
A better strateg...
Getting View's coordinates relative to the root layout
... offsetViewBounds = new Rect();
//returns the visible bounds
childView.getDrawingRect(offsetViewBounds);
// calculates the relative coordinates to the parent
parentViewGroup.offsetDescendantRectToMyCoords(childView, offsetViewBounds);
int relativeTop = offsetViewBounds.top;
int relativeLeft = offs...
Pickle or json?
....
wget https://gist.github.com/jdimatteo/af317ef24ccf1b3fa91f4399902bb534/raw/03e8dbab11b5605bc572bc117c8ac34cfa959a70/pickle_vs_json.py
python pickle_vs_json.py
Results with python 2.7 on a decent 2015 Xeon processor:
Dir Entries Method Time Length
dump 10 JSON 0.017 1484510
load ...
What is the difference between .text, .value, and .value2?
...e cell possibly augmented with date or currency indicators; .Value2 is the raw underlying value stripped of any extraneous information.
range("A1") = Date
range("A1").numberformat = "yyyy-mm-dd"
debug.print range("A1").text
debug.print range("A1").value
debug.print range("A1").value2
'results from...
What are some good Python ORM solutions? [closed]
...ore.add(thing)
store.commit()
And it makes it painless to drop down into raw SQL when you need to:
store.execute('UPDATE bars SET bar_name=? WHERE bar_id like ?', [])
store.commit()
share
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imp...
Converting DateTime format using razor
...playFormat] attribute is only used in EditorFor/DisplayFor, and not by the raw HTML APIs like TextBoxFor. I got it working by doing the following,
Model:
[Display(Name = "When was that document issued ?")]
[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:d}")]
public DateTime? L...
Do unix timestamps change across timezones?
...ne independent, you said it yourself in UTC time. There are two offsets, a raw offset and DST offset. For example America/New_York raw offset is -18000, and DST offset is 3600, so from any UNIX timestamp you have to do the math UNIX + offset + dstOffset in order to get the New York timestamp.
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How to pull a random record using Django's ORM?
...ust one query (assuming Postgres):
random_instance_or_none = Model.objects.raw('''
select * from {0} limit 1
offset floor(random() * (select count(*) from {0}))
'''.format(Model._meta.db_table)).first()
Be aware that this will raise an index error if the table is empty. Write yourself a mod...
Count how many records are in a CSV Python?
...han Martijn Pieters's. For 10M lines, %time sum(1 for row in open("df_data_raw.csv")) cost 4.91s while %time len(open("df_data_raw.csv").readlines()) cost 14.6s.
– Pengju Zhao
May 13 '18 at 9:13
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