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Filter data.frame rows by a logical condition
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To select rows according to one 'cell_type' (e.g. 'hesc'), use ==:
expr[expr$cell_type == "hesc", ]
To select rows according to two or more different 'cell_type', (e.g. either 'hesc' or 'bj fibroblast'), use %in%:
expr[expr$...
Pushing to Git returning Error Code 403 fatal: HTTP request failed
...ur repo directory
find url=entry under section [remote "origin"]
change it from url=https://MichaelDrogalis@github.com/derekerdmann/lunch_call.git to url=git@github.com/derekerdmann/lunch_call.git. that is, change all the texts before @ symbol to ssh://git
Save config file and quit. now you could...
How to get the max of two values in MySQL?
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Use GREATEST()
E.g.:
SELECT GREATEST(2,1);
Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)
s...
MySQL table is marked as crashed and last (automatic?) repair failed
... This was a quick fix! Had a "bad" options table. Make sure that you select the correct database first !
– jyllstuart
Jan 10 '19 at 15:54
add a comment
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IN vs OR in the SQL WHERE Clause
...h are nearly instant. When the column is not indexed I got these results:
SELECT COUNT(*) FROM t_inner WHERE val IN (1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000);
1 row fetched in 0.0032 (1.2679 seconds)
SELECT COUNT(*) FROM t_inner WHERE val = 1000 OR val = 2000 OR val = 3000 OR val = 40...
Generate a random alphanumeric string in Cocoa
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@orkoden thanks, my code was from some iOS 5 code. I'll update my answer to use the newer iOS 6/OS X 10.8 API.
– Abhi Beckert
Feb 24 '14 at 12:58
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How do I grant myself admin access to a local SQL Server instance?
...he "SQL Server Configuration Manager", right click the server instance and select properties, go to the tab "Startup Parameters" and add -m.
– maets
May 5 '15 at 13:32
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Clear variable in python
...efined it in the first place. A value of None in Python is quite different from an undefined variable. None is quite like most other incarnations of null, however (until we get into more arcane details, at least).
– Ben
Nov 23 '11 at 5:57
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How do you perform a left outer join using linq extension methods
...=> bar.Foo_Id,
(x,y) => new { Foo = x, Bars = y })
.SelectMany(
x => x.Bars.DefaultIfEmpty(),
(x,y) => new { Foo=x.Foo, Bar=y});
share
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improve t...
memcpy() vs memmove()
...t) manner. Simplistically, it just loops over the data (in order), copying from one location to the other. This can result in the source being overwritten while it's being read.
Memmove does more work to ensure it handles the overlap correctly.
EDIT:
(Unfortunately, I can't find decent examples, ...