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If list index exists, do X
In my program, user inputs number n , and then inputs n number of strings, which get stored in a list.
12 Answers
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What's the difference between “squash” and “fixup” in Git/Git Extension?
...the commit log message begins with "squash! ..." (or "fixup!
..."), and there is a commit whose title begins with the same ...,
automatically modify the todo list of rebase -i so that the commit
marked for squashing comes right after the commit to be modified,
and change ...
Extracting just Month and Year separately from Pandas Datetime column
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If you want new columns showing year and month separately you can do this:
df['year'] = pd.DatetimeIndex(df['ArrivalDate']).year
df['month'] = pd.DatetimeIndex(df['ArrivalDate']).month
or...
df['year'] = df['ArrivalDate'].dt.year
df['month'] = df['ArrivalDat...
Structs in Javascript
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The only difference between object literals and constructed objects are the properties inherited from the prototype.
var o = {
'a': 3, 'b': 4,
'doStuff': function() {
alert(this.a + this.b);
}
};
o.doStuff(); // displays: 7
You could make a struct factor...
In Python, how can you load YAML mappings as OrderedDicts?
I'd like to get PyYAML 's loader to load mappings (and ordered mappings) into the Python 2.7+ OrderedDict type, instead of the vanilla dict and the list of pairs it currently uses.
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LINQ with groupby and count
...g>, where each Grouping itself exposes the Key used to create the group and also is an IEnumerable<T> of whatever items are in your original data set. You just have to call Count() on that Grouping to get the subtotal.
foreach(var line in data.GroupBy(info => info.metric)
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Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
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How to get index using LINQ? [duplicate]
... edited Dec 30 '16 at 7:15
Andrew Savinykh
21.2k1212 gold badges8383 silver badges138138 bronze badges
answered Mar 18 '10 at 16:35
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How to read data when some numbers contain commas as thousand separator?
... some of the numerical values are expressed as strings with commas as thousand separator, e.g. "1,513" instead of 1513 . What is the simplest way to read the data into R?
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How do I move a redis database from one server to another?
I currently have a live redis server running on a cloud instance and I want to migrate this redis server to a new cloud instance and use that instance as my new redis server. If it were MySQL, I would export the DB from the old server and import it into the new server. How should I do this with redi...