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Immutable vs Mutable types
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What? Floats are immutable? But can't I do
x = 5.0
x += 7.0
print x # 12.0
Doesn't that "mut" x?
Well you agree strings are immutable right? But you can do the same thing.
s = 'foo'
s += 'bar'
print s # foobar
The value of the variable changes, but it changes by changing what the ...
Get a list of distinct values in List
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Not before the Distinct() but after, if you are trying to convert to a list. Ex: Notes.Select(x => x.Author).Distinct().ToList();
– MTwiford
Apr 4 '17 at 20:03
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Is the ternary operator faster than an “if” condition in Java [duplicate]
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Ternary Operator example:
int a = (i == 0) ? 10 : 5;
You can't do assignment with if/else like this:
// invalid:
int a = if (i == 0) 10; else 5;
This is a good reason to use the ternary operator. If you don't have an assignment:
(i == 0) ? foo ...
Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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How do I get the size of a java.sql.ResultSet?
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Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the entire data.
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How to get Latitude and Longitude of the mobile device in android?
...ness.
LocationFinder
public class LocationFinder extends Activity {
int increment = 4;
MyLocation myLocation = new MyLocation();
// private ProgressDialog dialog;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView...
String contains - ignore case [duplicate]
...lic boolean regionMatches(boolean ignoreCase,
int toffset,
String other,
int ooffset,
int len)
ignoreCase : if true, ignores case when comparing characters.
public static boolean co...
Select rows of a matrix that meet a condition
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This is easier to do if you convert your matrix to a data frame using as.data.frame(). In that case the previous answers (using subset or m$three) will work, otherwise they will not.
To perform the operation on a matrix, you can define a column by nam...
Why can't variable names start with numbers?
...a string of digits would be a valid identifier as well as a valid number.
int 17 = 497;
int 42 = 6 * 9;
String 1111 = "Totally text";
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Is it OK to use == on enums in Java?
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Thanks! I guess if I had just thought to step into .equals() with the compiler I would have seen this...
– Kip
Feb 10 '09 at 21:44
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