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Show the progress of a Python multiprocessing pool imap_unordered call?
...attributes of the result set:
from __future__ import division
import sys
for i, _ in enumerate(p.imap_unordered(do_work, xrange(num_tasks)), 1):
sys.stderr.write('\rdone {0:%}'.format(i/num_tasks))
share
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How do I create a variable number of variables?
...t; x = "spam"
>>> z = {x: "eggs"}
>>> z["spam"]
'eggs'
For cases where you're thinking of doing something like
var1 = 'foo'
var2 = 'bar'
var3 = 'baz'
...
a list may be more appropriate than a dict. A list represents an ordered sequence of objects, with integer indices:
lst = ...
How to plot two columns of a pandas data frame using points?
...like to plot values from one column versus the values from another column. Fortunately, there is plot method associated with the data-frames that seems to do what I need:
...
Is 'switch' faster than 'if'?
...gh, as it only works when the input can be bounded some way.
C Pseudocode for a "jump table" would be something like this -- note that the compiler in practice would need to insert some form of if test around the table to ensure that the input was valid in the table. Note also that it only works in...
How to downgrade or install an older version of Cocoapods
...havior, but sudo gem install cocoapods -v 0.39.0 alone didn't do the trick for me once I had 1.0.0.
– fullofsquirrels
May 23 '16 at 16:43
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How to split a string literal across multiple lines in C / Objective-C?
... Line2";
Better approach
There's a better approach that works just for strings.
Plain C:
char *my_string = "Line 1 "
"Line 2";
Objective-C:
NSString *my_string = @"Line1 "
"Line2"; // the second @ is optional
The second approach is better, b...
Comma in C/C++ macro
...e angle brackets like it does within parentheses. (This is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remai...
Structure padding and packing
...- say, int members would have offsets, which are mod(4) == 0 on 32-bit platform. Padding is on by default. It inserts the following "gaps" into your first structure:
struct mystruct_A {
char a;
char gap_0[3]; /* inserted by compiler: for alignment of b */
int b;
char c;
char gap...
What's the cleanest way of applying map() to a dictionary in Swift?
...lue in (key.uppercased(), value.lowercased()) })
There are also new APIs for merging dictionaries together, substituting a default value for missing elements, grouping values (converting a collection into a dictionary of arrays, keyed by the result of mapping the collection over some function), an...
Why doesn't list have safe “get” method like dictionary?
...hat a valid list index is, but there's no particularly good way to do this for key values in a dictionary.
– Nick Bastin
Feb 26 '11 at 7:35
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