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How to get a substring of text?
I have text with length ~700. How do I get only ~30 of its first characters?
5 Answers
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Select by partial string from a pandas DataFrame
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Based on github issue #620, it looks like you'll soon be able to do the following:
df[df['A'].str.contains("hello")]
Update: vectorized string methods (i.e., Series.str) are available in pandas 0.8.1 and up.
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How do I use a Boolean in Python?
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Transcendence
2,07622 gold badges1818 silver badges3030 bronze badges
answered Nov 17 '09 at 12:51
Bastien LéonardBa...
Does C have a “foreach” loop construct?
...#define foreach(item, array) \
for(int keep = 1, \
count = 0,\
size = sizeof (array) / sizeof *(array); \
keep && count != size; \
keep = !keep, count++) \
for(item = (array) + count; keep; keep = !keep)
And can be used like
int values[] =...
pyplot axes labels for subplots
...mmon labels.
import random
import matplotlib.pyplot as plt
x = range(1, 101)
y1 = [random.randint(1, 100) for _ in xrange(len(x))]
y2 = [random.randint(1, 100) for _ in xrange(len(x))]
fig = plt.figure()
ax = fig.add_subplot(111) # The big subplot
ax1 = fig.add_subplot(211)
ax2 = fig.add_subpl...
Stack smashing detected
...ollowing snippet:
#include <stdio.h>
void func()
{
char array[10];
gets(array);
}
int main(int argc, char **argv)
{
func();
}
The compiler, (in this case gcc) adds protection variables (called canaries) which have known values. An input string of size greater than 10 causes co...
How are booleans formatted in Strings in Python?
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answered Feb 13 '10 at 22:07
danbendanben
70.8k1818 gold badges113113 silver badges140140 bronze badges
...
How does a UILabel's minimumScaleFactor work?
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205
You need to set the label.adjustsFontSizeToFitWidth = YES;
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Initializing a struct to 0
...ves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewer initializers in a brace-e...
How can I pad a value with leading zeros?
...n for you, don't use this solution!
Potentially outdated: ECMAScript 2017 includes String.prototype.padStart and Number.prototype.toLocaleString is there since ECMAScript 3.1. Example:
var n=-0.1;
n.toLocaleString('en', {minimumIntegerDigits:4,minimumFractionDigits:2,useGrouping:false})
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