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How to add a progress bar to a shell script?
...ash use their own built-in echo command that doesn't accept "-n" ... so in order to accomplish the same thing you need to put \r\c at the end of the string, instead of just \r
– Justin Jenkins
Apr 2 '12 at 1:17
...
Can someone explain in simple terms to me what a directed acyclic graph is?
...Hence B depends on A or in better terms A has an edge directed to B. So in order to reach Node B you have to visit Node A. It will soon be clear that after adding all the subjects with its pre-requisites into a graph, it will turn out to be a Directed Acyclic Graph.
If there was a cycle then yo...
Replacing NAs with latest non-NA value
... = TRUE), y = sample(c(1:4, rep(NA, 4)), 20 , replace = TRUE))
dt <- dt[order(group)]
dt[, y_forward_fill := y[1], .(group, cumsum(!is.na(y)))]
dt
group y y_forward_fill
1: a NA NA
2: a NA NA
3: a NA NA
4: a 2 2
5: a ...
What does “connection reset by peer” mean?
...cognize the connection; it will send back a packet with the RST bit set in order to forcibly close the connection.
This can happen if the other side crashes and then comes back up or if it calls close() on the socket while there is data from you in transit, and is an indication to you that some o...
Find rows that have the same value on a column in MySQL
...LECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) > 1
)
...
Memcached vs. Redis? [closed]
... can happen if you serialize stale data).
Lists (commands)
Redis lists are ordered collections of strings. They are optimized for inserting, reading, or removing values from the top or bottom (aka: left or right) of the list.
Redis provides many commands for leveraging lists, including commands to p...
How to pass an array within a query string?
...)
See comments for examples in node.js, Wordpress, ASP.net
Maintaining order:
One more thing to consider is that if you need to maintain the order of your items (i.e. array as an ordered list), you really only have one option, which is passing a delimited list of values, and explicitly convertin...
Reload .profile in bash shell script (in unix)?
...A COMMON MISTAKE AND CAUSES A LOT OF DEVELOPERS TO LOSE A LOT OF TIME.
In order for your changes applied in your script to have effect for the global environment the script has to be run with
.myscript.sh
command.
In order to make sure that you script is not runned in a subshel you can use thi...
Build tree array from flat array in javascript
...son file that I have to handle with javascript to make it hierarchical, in order to later build a tree.
Every entry of the json has :
id : a unique id,
parentId : the id of the parent node (which is 0 if the node is a root of the tree)
level : the level of depth in the tree
...
How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
...er chunks like so:
With Tally As
(
Select ROW_NUMBER() OVER ( ORDER BY s1.object_id ) - 1 As Num
From sys.sysobjects As s1
Cross Join sys.sysobjects As s2
)
Select Substring(T1.textCol, T2.Num * 8000 + 1, 8000)
From Table As T1
Cross Join Tally As T2
Where T2...