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Performance of FOR vs FOREACH in PHP
...g out on top (surprise, surprise).
//make a nicely random array
$aHash1 = range( 0, 999999 );
$aHash2 = range( 0, 999999 );
shuffle( $aHash1 );
shuffle( $aHash2 );
$aHash = array_combine( $aHash1, $aHash2 );
$start1 = microtime(true);
foreach($aHash as $key=>$val) $aHash[$key]++;
$end1 = micro...
How to modify list entries during for loop?
...r loop variant, looks cleaner to me than one with enumerate():
for idx in range(len(list)):
list[idx]=... # set a new value
# some other code which doesn't let you use a list comprehension
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Evaluate expression given as a string
... capture output and all warnings, errors and other messages along with the raw results:
> pander::evals("5+5")
[[1]]
$src
[1] "5 + 5"
$result
[1] 10
$output
[1] "[1] 10"
$type
[1] "numeric"
$msg
$msg$messages
NULL
$msg$warnings
NULL
$msg$errors
NULL
$stdout
NULL
attr(,"class")
[1] "eval...
Convert JSON String To C# Object
...
It looks like you're trying to deserialize to a raw object. You could create a Class that represents the object that you're converting to. This would be most useful in cases where you're dealing with larger objects or JSON Strings.
For instance:
class Test {
S...
Convert a Unicode string to a string in Python (containing extra symbols)
...\x9c10'
>>> s.encode('utf16')
'\xff\xfe\x9c\x001\x000\x00'
This raw string of bytes can be written to a file. However, note that when reading it back, you must know what encoding it is in and decode it using that same encoding.
When writing to files, you can get rid of this manual encode...
SSL Error: unable to get local issuer certificate
...sudo apt install build-essential checkinstall libssl-dev
curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.35.1/install.sh | bash
nvm --version
nvm ls
nvm ls-remote
nvm install [version.number]
this should solve your problem
...
Regular Expression for alphanumeric and underscores
...ntation at the above links states that \w will "Match any character in the range 0 - 9, A - Z and a - z (equivalent of POSIX [:alnum:])", I have not found this to be true. Not with grep -P anyway. You need to explicitly include the underscore if you use [:alnum:] but not if you use \w. You can't bea...
Hash Map in Python
...class HashMap:
def __init__(self):
self.store = [None for _ in range(16)]
def get(self, key):
index = hash(key) & 15
if self.store[index] is None:
return None
n = self.store[index]
while True:
if n.key == key:
...
How do I use Django templates without the rest of Django?
...nment().compile('{% for row in data %}{{ row.name | upper }}{% endfor %}', raw=True)
from __future__ import division
from jinja2.runtime import LoopContext, Context, TemplateReference, Macro, Markup, TemplateRuntimeError, missing, concat, escape, markup_join, unicode_join
name = None
def root(cont...
Filter dataframe rows if value in column is in a set list of values [duplicate]
...
you can also use ranges by using:
b = df[(df['a'] > 1) & (df['a'] < 5)]
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