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How to get rspec-2 to give the full trace associated with a test failure?
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244
You must run rspec with -b option to see full backtraces
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How to take the first N items from a generator or list in Python? [duplicate]
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526
Slicing a list
top5 = array[:5]
To slice a list, there's a simple syntax: array[start:stop:...
Create Pandas DataFrame from a string
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A simple way to do this is to use StringIO.StringIO (python2) or io.StringIO (python3) and pass that to the pandas.read_csv function. E.g:
import sys
if sys.version_info[0] < 3:
from StringIO import StringIO
else:
from io import StringIO
import pandas as pd
TESTDATA = ...
How to avoid warning when introducing NAs by coercion
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142
Use suppressWarnings():
suppressWarnings(as.numeric(c("1", "2", "X")))
[1] 1 2 NA
This supp...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...t's an EXAMPLE.
BEGIN;
UPDATE testtable
SET somedata = 'blah'
WHERE id = 2;
-- Remember, this is WRONG. Do NOT COPY IT.
INSERT INTO testtable (id, somedata)
SELECT 2, 'blah'
WHERE NOT EXISTS (SELECT 1 FROM testtable WHERE testtable.id = 2);
COMMIT;
then when two run at once there are several f...
Laravel migration: unique key is too long, even if specified
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how to get the one entry from hashmap without iterating
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answered Oct 2 '09 at 13:23
Per ÖstlundPer Östlund
1,15477 silver badges66 bronze badges
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Extract a number from a string (JavaScript)
I have a string in JavaScript like #box2 and I just want the 2 from it.
21 Answers
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How to mark a build unstable in Jenkins when running shell scripts
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edited Oct 29 '13 at 9:22
answered Nov 16 '11 at 8:10
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How to initialize an array's length in JavaScript?
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edited Jul 7 '15 at 15:21
answered Jan 31 '11 at 14:32
F...