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NSUserDefaults - How to tell if a key exists
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382
objectForKey: will return nil if it doesn't exist.
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Android Writing Logs to text File
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outkkastoutkkast
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Amazon S3 Change file download name
I have files stored on S3 with a GUID as the key name.
7 Answers
7
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Find the max of two or more columns with pandas
...>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0 1
1 8
2 3
and so:
>>> df["C"] = ...
java: HashMap not working
...difference in the code. Auto-boxing means you can write:
myMap.put("foo", 3);
instead of:
myMap.put("foo", new Integer(3));
Auto-boxing means the first version is implicitly converted to the second. Auto-unboxing means you can write:
int i = myMap.get("foo");
instead of:
int i = myMap.get(...
Is there any particular difference between intval and casting to int - `(int) X`?
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193
intval() can be passed a base from which to convert. (int) cannot.
int intval( mixed $var [, i...
How to Implement Custom Table View Section Headers and Footers with Storyboard
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RobRob
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AJAX in Chrome sending OPTIONS instead of GET/POST/PUT/DELETE?
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136
Chrome is preflighting the request to look for CORS headers. If the request is acceptable, it ...
Status bar and navigation bar appear over my view's bounds in iOS 7
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answered Sep 13 '13 at 11:52
NandhaNandha
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Getting a structural type with an anonymous class's methods from a macro
...ral type with the named member. */
def bar(name: String): Any = macro bar_impl
def bar_impl(c: Context)(name: c.Expr[String]) = {
import c.universe._
val anon = TypeName(c.freshName)
// next week, val q"${s: String}" = name.tree
val Literal(Constant(s: String)) = name.tree
v...