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SQL Data Reader - handling Null column values
...
For a string you can simply cast the object version (accessed using the array operator) and wind up with a null string for nulls:
employee.FirstName = (string)sqlreader[indexFirstName];
or
employee.FirstName = sqlreader[indexFirstName] as string;
For integers, if you cast to a nullable int,...
ActiveRecord: size vs count
...rform an SQL COUNT query
length will calculate the length of the resulting array
size will try to pick the most appropriate of the two to avoid excessive queries
But there is one more thing. We noticed a case where size acts differently to count/lengthaltogether, and I thought I'd share it since i...
C/C++ line number
...N__ were treated as string literals; they could be used to initialize char arrays, and they could be concatenated with other string literals. GCC 3.4 and later treat them as variables, like __func__. In C++, __FUNCTION__ and __PRETTY_FUNCTION__ have always been variables."
– Jo...
Haversine Formula in Python (Bearing and Distance between two GPS points)
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There is also a vectorized implementation, which allows to use 4 numpy arrays instead of scalar values for coordinates:
def distance(s_lat, s_lng, e_lat, e_lng):
# approximate radius of earth in km
R = 6373.0
s_lat = s_lat*np.pi/180.0
s_lng = np.deg2rad(s_lng...
What does O(log n) mean exactly?
...binary search. Another example is quick sort where each time we divide the array into two parts and each time it takes O(N) time to find a pivot element. Hence it N O(log N)
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AngularJS For Loop with Numbers & Ranges
...amic range.
var range = _.range(1, 11);
// val will be each number in the array not the index.
<div ng-repeat='val in range'>
{{ $index }}: {{ val }}
</div>
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When to use symbols instead of strings in Ruby?
...all_symbols:
symbols_count = Symbol.all_symbols.count # all_symbols is an array with all
# instantiated symbols.
a = :one
puts a.object_id
# prints 167778
a = :two
puts a.object_id
# prints 167858
a = :one
puts a.object_id
# prints 167778 again - the sa...
Difference between int32, int, int32_t, int8 and int8_t
...s (especially while handling memory mapped I/O or may be consider a simple array situation), so it is highly recommended to specify fixed size variables. In legacy systems you may come across
typedef short INT16;
typedef int INT32;
typedef long INT64;
Starting from C99, the designers added s...
How do I get a list of all the duplicate items using pandas in python?
...ou actually do not have to add == True, .duplicated() already returns bool array.
– Jakub Wagner
Apr 9 at 7:36
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How to get an enum which is created in attrs.xml in code
...ML files (as you show).
You could do this in your view constructor:
TypedArray a = context.getTheme().obtainStyledAttributes(
attrs,
R.styleable.IconView,
0, 0);
// Gets you the 'value' number - 0 or 666 in your example
if (a.hasValue(R.styl...