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How do I execute a string containing Python code in Python?
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For statements, use exec(string) (Python 2/3) or exec string (Python 2):
>>> mycode = 'print "hello world"'
>>> exec(mycode)
Hello world
When you need the value of an expression, use eval(string):
>>> x = eval("2+2")
>>> x
4
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
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102
Granted that the behavior is inconsistent, but I think it's easy to imagine cases where this is ...
Facebook API “This app is in development mode”
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205
I know its a little bit late but someone may find this useful in future.
STEP 1:
Login to fa...
PostgreSQL: Which Datatype should be used for Currency?
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Numeric with forced 2 units precision. Never use float or float like datatype to represent currency because if you do, people are going to be unhappy when the financial report's bottom line figure is incorrect by + or - a few dollars.
The mon...
Generating random numbers in Objective-C
...C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
u_int32_t
arc4random(void);
void
arc4random_stir(void);
void
arc4random_addrandom(unsigned char *dat, int datlen);
DESCRIPTION
The arc4random() function uses the key stream generator employed by the...
Inserting image into IPython notebook markdown
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213
Files inside the notebook dir are available under a "files/" url. So if it's in the base path...
What is the maximum float in Python?
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279
For float have a look at sys.float_info:
>>> import sys
>>> sys.float_info
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AJAX Mailchimp signup form integration
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242
You don't need an API key, all you have to do is plop the standard mailchimp generated form in...
How to install psycopg2 with “pip” on Python?
I'm using virtualenv and I need to install "psycopg2".
33 Answers
33
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