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Eclipse - Unable to install breakpoint due to missing line number attributes
...
I had the same error message in Eclipse 3.4.1, SUN JVM1.6.0_07 connected to Tomcat 6.0 (running in debug-mode on a different machine, Sun JVM1.6.0_16, the debug connection did work correctly).
Window --> Preferences --> Java --> Compiler --> Classfile Generation: "add li...
Primary key or Unique index?
.... Example:
CREATE TABLE table1 (foo int, bar int);
CREATE UNIQUE INDEX ux_table1_foo ON table1(foo); -- Create unique index on foo.
INSERT INTO table1 (foo, bar) VALUES (1, 2); -- OK
INSERT INTO table1 (foo, bar) VALUES (2, 2); -- OK
INSERT INTO table1 (foo, bar) VALUES (3, 1); -- OK
INSERT INTO...
Convert to binary and keep leading zeros in Python
...n using format():
>>> import timeit
>>> timeit.timeit("f_(v, '#010b')", "v = 14; f_ = format") # use a local for performance
0.40298633499332936
>>> timeit.timeit("f'{v:#010b}'", "v = 14")
0.2850222919951193
But I'd use that only if performance in a tight loop matters,...
cartesian product in pandas
...
Use pd.MultiIndex.from_product as an index in an otherwise empty dataframe, then reset its index, and you're done.
a = [1, 2, 3]
b = ["a", "b", "c"]
index = pd.MultiIndex.from_product([a, b], names = ["a", "b"])
pd.DataFrame(index = index).res...
Add column with constant value to pandas dataframe [duplicate]
...le times.
# Wrong
df['new'] = [[]] * len(df)
# Right
df['new'] = [[] for _ in range(len(df))]
Generating a copy: df.assign(new=0)
If you need a copy instead, use DataFrame.assign:
df.assign(new='y')
A B C new
0 x x x y
1 x x x y
2 x x x y
3 x x x y
And, if you ne...
Android studio - Failed to find target android-18
...under SDK 18. No need to hack the manifest files.
Fixed by:
export ANDROID_HOME= pathtobundle/adt-bundle-linux-x86_64-20130729/sdk
If you don't have the ADT installed, and just want the SDK, it seems like a good solution is to install everything and then point Android Studio to the just the packag...
What's the difference between %s and %d in Python string formatting?
...as a replaceable variable. For example, if you create 2 variables
variable_one = "Stackoverflow"
variable_two = 45
you can assign those variables to a sentence in a string using a tuple of the variables.
variable_3 = "I was searching for an answer in %s and found more than %d answers to my quest...
namespaces for enum types - best practices
...m
{
Red,
Blue,
Green,
Yellow
} enum_type;
private:
enum_type _val;
public:
Color(enum_type val = Blue)
: _val(val)
{
assert(val <= Yellow);
}
operator enum_type() const
{
return _val;
}
};
void SetPenC...
Disable all table constraints in Oracle
...m SQL*Plus or put this thing into a package or procedure. The join to USER_TABLES is there to avoid view constraints.
It's unlikely that you really want to disable all constraints (including NOT NULL, primary keys, etc). You should think about putting constraint_type in the WHERE clause.
BEGIN
...
Cocoa Touch: How To Change UIView's Border Color And Thickness?
...st a heads up for others. Xcode suggests bridging UIColor to CGColorRef as __bridge CGColorRef. This does not work. It needs to be [UIColor blackColor].CGColor as mentioned in answer.
– GoodSp33d
Jul 10 '14 at 5:05
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