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How to use the PI constant in C++
...ially older) platforms (see the comments below) you might need to
#define _USE_MATH_DEFINES
and then include the necessary header file:
#include <math.h>
and the value of pi can be accessed via:
M_PI
In my math.h (2014) it is defined as:
# define M_PI 3.1415926535897932384...
Why doesn't Python have a sign function?
...y removed and replaced by sign! Have you never implemented a class with a __cmp__ method? Have you never called cmp and specified a custom comparator function?
In summary, I've found myself wanting a sign function too, but copysign with the first argument being 1 will work just fine. I disagree ...
Is there a typical state machine implementation pattern?
... use a table driven approach for most state machines:
typedef enum { STATE_INITIAL, STATE_FOO, STATE_BAR, NUM_STATES } state_t;
typedef struct instance_data instance_data_t;
typedef state_t state_func_t( instance_data_t *data );
state_t do_state_initial( instance_data_t *data );
state_t do_state_f...
python: Change the scripts working directory to the script's own directory
..., you can use the os.path functions:
import os
abspath = os.path.abspath(__file__)
dname = os.path.dirname(abspath)
os.chdir(dname)
This takes the filename of your script, converts it to an absolute path, then extracts the directory of that path, then changes into that directory.
...
Does using “new” on a struct allocate it on the heap or stack?
...eterisedCtorAssignToField() cil managed
{
.maxstack 8
L_0001: ldstr ""
L_0006: newobj instance void [mscorlib]System.Guid::.ctor(string)
L_000b: stsfld valuetype [mscorlib]System.Guid Test::field
L_0010: ret
}
.method private hidebysig static...
How do you debug PHP scripts? [closed]
...step into the code is a much better way to debug then the old method of var_dump and print at various points to see where your flow goes wrong. When all else fails though and all I have is SSH and vim I still var_dump()/die() to find where the code goes south.
...
How can I use pickle to save a dict?
...ickle', 'wb') as handle:
pickle.dump(a, handle, protocol=pickle.HIGHEST_PROTOCOL)
with open('filename.pickle', 'rb') as handle:
b = pickle.load(handle)
print a == b
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Why does using an Underscore character in a LIKE filter give me all the results?
...
Modify your WHERE condition like this:
WHERE mycolumn LIKE '%\_%' ESCAPE '\'
This is one of the ways in which Oracle supports escape characters. Here you define the escape character with the escape keyword. For details see this link on Oracle Docs.
The '_' and '%' are wildcards in a ...
Is it ok to use dashes in Python files when trying to import them?
...o import a file with a dash in its name, you can do the following::
python_code = __import__('python-code')
But, as also mentioned above, this is not really recommended. You should change the filename if it's something you control.
...
Remove HTML Tags in Javascript with Regex
... +1 thanks. this one liner woked perfect for my needs. console.log( my_html.replace(/(&nbsp;|<([^>]+)>)/ig, "") );
– DaveAlger
May 3 '15 at 0:29
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