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How to reset index in a pandas dataframe? [duplicate]
...ame from which I remove some rows. As a result, I get a dataframe in which index is something like that: [1,5,6,10,11] and I would like to reset it to [0,1,2,3,4] . How can I do it?
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Add object to ArrayList at specified index
...ider using a regular Array, initialize the capacity and put objects at the index you want.
Object[] list = new Object[10];
list[0] = object1;
list[2] = object3;
list[1] = object2;
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source of historical stock data [closed]
...my 2¢, it's my job to get good and clean data for a hedge-fund, I've seen quite a lot of data feeds and historical data providers. This is mainly about US stock data.
To start with, if you have some money don't bother with downloading data from Yahoo, get the end of day data straight from CSI data...
Exception thrown in NSOrderedSet generated accessors
...>";
- (void)insertObject:(<#Type#> *)value in<#Property#>AtIndex:(NSUInteger)idx {
NSIndexSet* indexes = [NSIndexSet indexSetWithIndex:idx];
[self willChange:NSKeyValueChangeInsertion valuesAtIndexes:indexes forKey:kItemsKey];
NSMutableOrderedSet *tmpOrderedSet = [NSMutab...
How to remove an element from a list by index
How do I remove an element from a list by index in Python?
18 Answers
18
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How do you use String.substringWithRange? (or, how do Ranges work in Swift?)
...You can use the substringWithRange method. It takes a start and end String.Index.
var str = "Hello, playground"
str.substringWithRange(Range<String.Index>(start: str.startIndex, end: str.endIndex)) //"Hello, playground"
To change the start and end index, use advancedBy(n).
var str = "Hello...
Which characters make a URL invalid?
...racters) may contain any of the following 84 characters:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;=
Note that this list doesn't state where in the URI these characters may occur.
Any other character needs to be encoded with the percent-encoding (%hh...
Get the index of the object inside an array, matching a condition
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As of 2016, you're supposed to use Array.findIndex (an ES2015/ES6 standard) for this:
a = [
{prop1:"abc",prop2:"qwe"},
{prop1:"bnmb",prop2:"yutu"},
{prop1:"zxvz",prop2:"qwrq"}];
index = a.findIndex(x => x.prop2 ==="yutu");
console.log(index);
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How to get index in Handlebars each helper?
...m using Handlebars for templating in my project. Is there a way to get the index of the current iteration of an "each" helper in Handlebars?
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For-each over an array in JavaScript
...ent above, the callback is called with three: The value of each entry, the index of that entry, and a reference to the array you're iterating over (in case your function doesn't already have it handy).
Unless you're supporting obsolete browsers like IE8 (which NetApps shows at just over 4% market s...