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How to loop over files in directory and change path and add suffix to filename
...ch (which makes the loop variable expand to the (un-matching) glob pattern string itself).
For example:
for filename in Data/*.txt; do
[ -e "$filename" ] || continue
# ... rest of the loop body
done
Reference: Bash Pitfalls
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Converting a JS object to an array using jQuery
... (i.e. in this example they are 1 and 2 - but they could just as well be a string key or non sequential number
– Simon_Weaver
May 31 '16 at 2:41
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
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Ruby hash-keys assigned by hash-rockets can facilitate strings for key-value pairs (e.g. 's' => x) whereas key assignment via symbols (e.g. key: "value" or :key => "value") cannot be assigned with strings. Although hash-rockets provide freedom and functionality for hash-ta...
SQL to determine minimum sequential days of access?
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@Artem: That was what I initially thought but when I thought about it, if you have an index on (UserId, CreationDate), the records will show up consecutively in the index and it should perform well.
– Mehrdad Afshari
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Circle line-segment collision detection algorithm?
... exdx + eydy - dxh - dyk ) +
ex2 + ey2 -
2exh - 2eyk + h2 + k2 - r2 = 0
Finally,
t2( _d * _d ) + 2t( _e * _d - _d * _c ) + _e * _e - 2( _e*_c ) + _c * _c - r2 = 0
*Where _d is the vector d and * is the dot product.*
And then,
t2( _d * _d ) + 2t( _d * ( _e - _c ) ) + ( _e - _c ) * ( _e - _c ) - r2 = ...
Preserving signatures of decorated functions
... decorator that does something very generic. For example, it might convert all arguments to a specific type, perform logging, implement memoization, etc.
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Linq to Sql: Multiple left outer joins
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This may be cleaner (you dont need all the into statements):
var query =
from order in dc.Orders
from vendor
in dc.Vendors
.Where(v => v.Id == order.VendorId)
.DefaultIfEmpty()
from status
in dc.Status
.Where(...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
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There are multiple reasons why the C compiler cannot automatically reorder the fields:
The C compiler doesn't know whether the struct represents the memory structure of objects beyond the current compilation unit (for example: a foreign library, a file on disc, network data, CPU page ...
What's the 'environment' task in Rake?
...pers, etc. Without the :environment, you won't have access to any of those extras.
Also => :environment itself does not make available any environment-related variables, e.g. environment, @environment, RAILS_ENV, etc.
sh...
IN vs OR in the SQL WHERE Clause
... say you should profile on a specific implementation. I'd imagine that the extra structure of the IN method makes it easier to optimize than a whole bunch of possibly related OR clauses. I'd be surprised if there is an engine where the OR method is faster, but I'm not surprised that there are times ...