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File content into unix variable with newlines
...anscript for a demo:
pax> cat num1.txt ; x=$(cat num1.txt)
line 1
line 2
pax> echo $x ; echo '===' ; echo "$x"
line 1 line 2
===
line 1
line 2
The reason why newlines are replaced with spaces is not entirely to do with the echo command, rather it's a combination of things.
When given a ...
MySQL ON vs USING?
...d to just say film_id since that would make for an ambiguity:
ERROR 1052 (23000): Column 'film_id' in field list is ambiguous
As for select *, the joining column appears in the result set twice with ON while it appears only once with USING:
mysql> create table t(i int);insert t select 1;c...
ValidateRequest=“false” doesn't work in Asp.Net 4
I have a form at which I use ckeditor. This form worked fine at Asp.Net 2.0 and 3.5 but now it doesn't work in Asp.Net 4+. I have ValidateRequest="false" directive. Any suggestions?
...
Adding a Method to an Existing Object Instance
...t "fooFighters"
...
>>> A.fooFighters = fooFighters
>>> a2 = A()
>>> a2.fooFighters
<bound method A.fooFighters of <__main__.A instance at 0x00A9BEB8>>
>>> a2.fooFighters()
fooFighters
Previously defined instances are updated as well (as long as they ...
Is it correct to use JavaScript Array.sort() method for shuffling?
...
12 Answers
12
Active
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What does the number in parentheses shown after Unix command names in manpages mean?
For example: man(1) , find(3) , updatedb(2) ?
7 Answers
7
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How to plot two histograms together in R?
...data and combine them.
carrots <- data.frame(length = rnorm(100000, 6, 2))
cukes <- data.frame(length = rnorm(50000, 7, 2.5))
# Now, combine your two dataframes into one.
# First make a new column in each that will be
# a variable to identify where they came from later.
carrots$veg <- ...
Python SQL query string formatting
...p://docs.python.org/), which could be qualified a somewhere between Option 2 and Option 4
Code Sample:
sql = ("SELECT field1, field2, field3, field4 "
"FROM table "
"WHERE condition1=1 "
"AND condition2=2;")
Works as well with f-strings:
fields = "field1, field2, field3, fi...
How to get the input from the Tkinter Text Widget?
...
132
To get Tkinter input from the text box, you must add a few more attributes to the normal .get() ...
What is the difference between LL and LR parsing?
...→ T + E
E → T
T → int
Then given the string int + int + int, an LL(2) parser (which uses two tokens of lookahead) would parse the string as follows:
Production Input Action
---------------------------------------------------------
S int + int + int Predi...