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How to add calendar events in Android?

I'm just getting up to speed on Android, and today in a project meeting someone said that Android has no native calendar app so users just use whatever calendar app they like. ...
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What does “hashable” mean in Python?

...ue which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method). Hashable objects which compare equal must have the same hash value. Hashability makes an object usable as a dictionary key and a set member...
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Apply a function to every row of a matrix or a data frame

Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R? ...
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What is the MySQL VARCHAR max size?

...ySQL table has a maximum row size limit of 65,535 bytes, not counting BLOB and TEXT types. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored separately from the rest of the row. Read more about Limits on Table Column Count and Row Size. ...
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Internet Explorer 11 detection

...t && !!document.documentMode; // true on IE11 // false on Edge and other IEs/browsers. Original Answer In order to check Ie11 , you can use this : ( tested) (or run this) !(window.ActiveXObject) && "ActiveXObject" in window I have all VMS of IE : Notice : this w...
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Tricks to manage the available memory in an R session

...ive R session? I use the functions below [based on postings by Petr Pikal and David Hinds to the r-help list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effective solution was ... to run under 64-bit Linux with ample memory. ...
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What are the Android SDK build-tools, platform-tools and tools? And which version should be used?

...imentary question, but to my surprise, I could not find any document about Android SDK Build-tools. Besides Android SDK Tools and Android SDK Platform-tools, there are a bunch of Android SDK Build-tools as shown in the appended screenshot. Could anyone point to a source explaining all of them and he...
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Is there a REAL performance difference between INT and VARCHAR primary keys?

...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables. ...
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Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3

I'm now reading documentation on Twitter Bootstrap 3, and tried to follow column ordering as shown in this page but hit the wall. I don't understand why such a code works nor how to correctly specify the setting. What I want to show is one grid, which is consisted of length 5, and the other leng...
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Ways to save enums in database

...store enumerations as numerical ordinal values anymore; it makes debugging and support way too difficult. We store the actual enumeration value converted to string: public enum Suit { Spade, Heart, Diamond, Club } Suit theSuit = Suit.Heart; szQuery = "INSERT INTO Customers (Name, Suit) " + ...