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UITableView - scroll to the top
In my table view I have to scroll to the top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
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Using IQueryable with Linq
...tabase, with many ORM systems, you have the option of fetching data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.
If you do:...
Force IE compatibility mode off using tags
...the standards supported by that version of IE (e.g., IE=8 will better obey table border spacing and some pseudo selectors than IE=7).
Whereas, the Emulate modes tell IE to follow any <!DOCTYPE> directives in your page, rendering standards mode based the version you choose and quirks mode bas...
Create table in SQLite only if it doesn't exist already
I want to create a table in a SQLite database only if doesn't exist already. Is there any way to do this? I don't want to drop the table if it exists, only create it if it doesn't.
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assertEquals vs. assertEqual in python
...ase methods had one or more aliases that are now deprecated. The following table lists the correct names along with their deprecated aliases:
Method Name | Deprecated alias | Deprecated alias
--------------+------------------+-----------------
assertEqual() | failUnlessEqual | assertEquals
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When to add what indexes in a table in Rails
... end of the index.
If you have a has_many :through relationship, your join table should have a unique index on both properties involved in the join as a compound key.
If you fetch a record directly using a unique identifier such as username or email, that should be a unique index.
If you fetch sets ...
Print only?
... but I had two troubles with it: for one if any of the element's parents established its own relative/absolute positioning the content would still be offset unless I used position:fixed instead. However, Chrome and Safari would also truncate content, especially after the first page. So my final work...
How to efficiently build a tree from a flat structure?
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Store IDs of the objects in a hash table mapping to the specific object. Enumerate through all the objects and find their parent if it exists and update its parent pointer accordingly.
class MyObject
{ // The actual object
public int ParentID { get; set; ...
How to convert a table to a data frame
I have a table in R that has str() of this:
5 Answers
5
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mmap() vs. reading blocks
...r random access, especially if your access patterns are sparse and unpredictable.
Memory maps allow you to keep using pages from the cache until you are done. This means that if you use a file heavily for a long period of time, then close it and reopen it, the pages will still be cached. With read...