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How do I set a variable to the output of a command in Bash?
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vstepaniuk
27022 silver badges88 bronze badges
answered Jan 10 '11 at 21:04
Andy LesterAndy Lester
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How to print a string in fixed width?
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EDIT 2013-12-11 - This answer is very old. It is still valid and correct, but people looking at this should prefer the new format syntax.
You can use string formatting like this:
>>> print '%5s' % 'aa'
aa
>>>...
isset() and empty() - what to use
...mpty checks if the variable is set and if it is it checks it for null, "", 0, etc
Isset just checks if is it set, it could be anything not null
With empty, the following things are considered empty:
"" (an empty string)
0 (0 as an integer)
0.0 (0 as a float)
"0" (0 as a string)
NULL
FALSE
array(...
How to get overall CPU usage (e.g. 57%) on Linux [closed]
...ke a look at cat /proc/stat
grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage "%"}'
EDIT please read comments before copy-paste this or using this for any serious work. This was not tested nor used, it's an idea for people who do not want to install a utility or for so...
Fill between two vertical lines in matplotlib
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import matplotlib.pyplot as plt
fig, ax = plt.subplots()
ax.plot(range(20))
ax.axvspan(8, 14, alpha=0.5, color='red')
plt.show()
You could use fill_betweenx to do this, but the extents (both x and y) of the rectangle would be in data coordinates. With axvspan, the y-extents of the rectangle...
Using NumberPicker Widget with Strings
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NumberPicker picker = new NumberPicker(this);
picker.setMinValue(0);
picker.setMaxValue(2);
picker.setDisplayedValues( new String[] { "Belgium", "France", "United Kingdom" } );
share
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im...
Convert JS date time to MySQL datetime
...nction to pad numbers to two digits…
**/
function twoDigits(d) {
if(0 <= d && d < 10) return "0" + d.toString();
if(-10 < d && d < 0) return "-0" + (-1*d).toString();
return d.toString();
}
/**
* …and then create the method to output the date string as ...
How do you read CSS rule values with JavaScript?
...(className) {
var cssText = "";
var classes = document.styleSheets[0].rules || document.styleSheets[0].cssRules;
for (var x = 0; x < classes.length; x++) {
if (classes[x].selectorText == className) {
cssText += classes[x].cssText || classes[x].style.cssText...
Is there an expression for an infinite generator?
...gument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One variant of particular note is iter(f, object()),...
Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
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As Sven mentioned, x[[[0],[2]],[1,3]] will give back the 0 and 2 rows that match with the 1 and 3 columns while x[[0,2],[1,3]] will return the values x[0,1] and x[2,3] in an array.
There is a helpful function for doing the first example I gave, n...