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Best way to test if a row exists in a MySQL table
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edited Sep 4 '19 at 19:20
SovietFrontier
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answered Nov 4 '09 ...
If vs. Switch Speed
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answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
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How do I trim leading/trailing whitespace in a standard way?
...m leading space
while(isspace((unsigned char)*str)) str++;
if(*str == 0) // All spaces?
return str;
// Trim trailing space
end = str + strlen(str) - 1;
while(end > str && isspace((unsigned char)*end)) end--;
// Write new null terminator character
end[1] = '\0';
re...
Check if character is number?
...
70
You could use comparison operators to see if it is in the range of digit characters:
var c = ju...
How do I check if there are duplicates in a flat list?
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406
Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 't...
Identifying the dependency relationship for python packages installed with pip
...ch displays dependencies as a tree structure e.g.:
$ pipdeptree
Lookupy==0.1
wsgiref==0.1.2
argparse==1.2.1
psycopg2==2.5.2
Flask-Script==0.6.6
- Flask [installed: 0.10.1]
- Werkzeug [required: >=0.7, installed: 0.9.4]
- Jinja2 [required: >=2.4, installed: 2.7.2]
- MarkupSafe...
Converting a column within pandas dataframe from int to string
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In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [18]: df.dtypes
Out[18]:
A int64
B int64
dtype: object
Convert a series
In [19]: df['A'].apply(str)
Ou...
Are members of a C++ struct initialized to 0 by default?
... constructors
struct Snapshot {
int x;
double y;
Snapshot():x(0),y(0) { }
// other ctors / functions...
};
Will initialize both x and y to 0. Note that you can use x(), y() to initialize them disregarding of their type: That's then value initialization, and usually yields a proper...
In php, is 0 treated as empty?
...ollowing things are considered to be empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array() (an empty array)
var $var; (a variable declared, but without a value in a class)
Note that this is exactly the same list as for a ...
Getting Java version at runtime
...nical Articles
J2SE SDK/JRE Version String Naming Convention
Version 1.5.0 or 5.0?
"J2SE also keeps the version number 1.5.0 (or 1.5) in some places that are visible only to developers, or where the version number is parsed by programs"
"java.version system property"
Version 1.6.0 Used by De...