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leading zeros in rails
...eld, if the user enters "1" I would like Rails to automatically pad it to "01" before saving it to the database. Also for the min field if the user enter "0" it should put in as "00".
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Make xargs execute the command once for each line of input
...
405
The following will only work if you do not have spaces in your input:
xargs -L 1
xargs --max-l...
What optimizations can GHC be expected to perform reliably?
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+150
This GHC Trac page also explains the passes fairly well. This page explains the optimization ordering, though, like the majority of th...
print call stack in C or C++
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80
For a linux-only solution you can use backtrace(3) that simply returns an array of void * (in fa...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
...ications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
I spent several days to solve this problem. I have tested many approaches that have been mentioned in different web sites, but non of them worked....
Correct way to convert size in bytes to KB, MB, GB in JavaScript
...bytes) {
var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
if (bytes == 0) return '0 Byte';
var i = parseInt(Math.floor(Math.log(bytes) / Math.log(1024)));
return Math.round(bytes / Math.pow(1024, i), 2) + ' ' + sizes[i];
}
Note : This is original code, Please use fixed version below. Ali...
How to calculate cumulative normal distribution?
...le:
>>> from scipy.stats import norm
>>> norm.cdf(1.96)
0.9750021048517795
>>> norm.cdf(-1.96)
0.024997895148220435
In other words, approximately 95% of the standard normal interval lies within two standard deviations, centered on a standard mean of zero.
If you need t...
efficient circular buffer?
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206
I would use collections.deque with a maxlen arg
>>> import collections
>>> d...
Get a random boolean in python?
...ter
$ python -m timeit -s "import random" "random.choice([True, False])"
1000000 loops, best of 3: 0.904 usec per loop
$ python -m timeit -s "import random" "random.choice((True, False))"
1000000 loops, best of 3: 0.846 usec per loop
$ python -m timeit -s "import random" "random.getrandbits(1)"
10...
How do you create a yes/no boolean field in SQL server?
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The equivalent is a BIT field.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).
When accessing the database through ASP.NET it will expose the field as a b...