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Adjust width of input field to its input
... of the character "m". This would be useful for calculating the width of a string. I've seen cross-browser issues with em units applied to some attributes though so do test it.
– Archonic
Apr 4 '13 at 4:46
...
Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...nging order and names of variables, shortening variables, changing case of strings). From this, you should be able to figure out what was missing from one or the other. For example (this is not very elegant):
difference <-
data.frame(lapply(1:ncol(a1),function(i)setdiff(a1[,i],comparison$tM[,...
PHP substring extraction. Get the string before the first '/' or the whole string
I am trying to extract a substring. I need some help with doing it in PHP.
15 Answers
...
Print string and variable contents on the same line in R
...
{glue} offers much better string interpolation, see my other answer. Also, as Dainis rightfully mentions, sprintf() is not without problems.
There's also sprintf():
sprintf("Current working dir: %s", wd)
To print to the console output, use cat() ...
Referring to the null object in Python
...Empty()
>>> empty==None
True
But then it also works on the empty string
>>> empty==''
True
And yet
>>> ''==None
False
>>> empty is None
False
Case 2: Using None as a boolean
The following two tests
if value:
# Do something
if not value:
# Do something
...
Types in MySQL: BigInt(20) vs Int(20)
...---+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+------------------+------+-----+---------+-------+
| id | int(20) unsigned | YES | | NULL | |
+-------+------------------+------+-----+---------+-------+
1 row in set (0,00 sec)
mysql> IN...
vertical-align with Bootstrap 3
...t;
</div>
</div>
Bootply
Using inline-block adds extra space between blocks if you let a real space in your code (like ...</div> </div>...). This extra space breaks our grid if column sizes add up to 12:
<div class="row">
<div class="col-xs-6 col-m...
async await return Task
...ot work (I guess I am doing something wrong). Example static async Task<string> DoStuff() { ... = await SomeMethodAsync(); return "string value"; } .. var x = DoStuff(); But this x - is with type "Task<string>", not with type "string"... Why is that so?
– Prokurors...
Convert a list to a string in C#
How do I convert a list to a string in C#?
13 Answers
13
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sqlite alter table add MULTIPLE columns in a single statement
...und for adding multiple columns using the benefit of transactions in SQL.
String alterTableQuery = "ALTER TABLE " + TABLE_NAME + " ADD COLUMN ";
List<String> newColumns = ..// Your new columns
db.beginTransaction();
for (String column : newColumns){
db.execSQL(alterTableQuery + column + ...