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Random, Datetime, Threading

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Jure Šorn 4 years ago
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README.md
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@ -513,9 +513,9 @@ from statistics import mean, median, variance, stdev, pvariance, pstdev
```python
from random import random, randint, choice, shuffle, gauss, seed
<float> = random()
<int> = randint(from_inclusive, to_inclusive)
<el> = choice(<list>)
<float> = random() # A float inside [0, 1).
<int> = randint(from_inc, to_inc) # An int inside [from_inc, to_inc].
<el> = choice(<list>) # Keeps the list intact.
```
### Bin, Hex
@ -614,15 +614,15 @@ from dateutil.tz import UTC, tzlocal, gettz, datetime_exists, resolve_imaginary
<tzinfo> = UTC # UTC timezone. London without DST.
<tzinfo> = tzlocal() # Local timezone. Also gettz().
<tzinfo> = gettz('<Continent>/<City>') # 'Continent/City_Name' timezone or None.
<DTa> = <DT>.astimezone(<tzinfo>) # Datetime, converted to passed timezone.
<Ta/DTa> = <T/DT>.replace(tzinfo=<tzinfo>) # Unconverted object with new timezone.
<DTa> = <DT>.astimezone(<tzinfo>) # Datetime, converted to the passed timezone.
<Ta/DTa> = <T/DT>.replace(tzinfo=<tzinfo>) # Unconverted object with a new timezone.
```
### Encode
```python
<D/T/DT> = D/T/DT.fromisoformat('<iso>') # Object from ISO string. Raises ValueError.
<DT> = DT.strptime(<str>, '<format>') # Datetime from str, according to format.
<D/DTn> = D/DT.fromordinal(<int>) # D/DTn from days since Christ, at midnight.
<D/DTn> = D/DT.fromordinal(<int>) # D/DTn from days since the Gregorian NYE 1.
<DTn> = DT.fromtimestamp(<real>) # Local time DTn from seconds since the Epoch.
<DTa> = DT.fromtimestamp(<real>, <tz.>) # Aware datetime from seconds since the Epoch.
```
@ -633,7 +633,7 @@ from dateutil.tz import UTC, tzlocal, gettz, datetime_exists, resolve_imaginary
```python
<str> = <D/T/DT>.isoformat(sep='T') # Also timespec='auto/hours/minutes/seconds'.
<str> = <D/T/DT>.strftime('<format>') # Custom string representation.
<int> = <D/DT>.toordinal() # Days since Christ, ignoring time and tz.
<int> = <D/DT>.toordinal() # Days since Gregorian NYE 1, ignoring time and tz.
<float> = <DTn>.timestamp() # Seconds since the Epoch, from DTn in local tz.
<float> = <DTa>.timestamp() # Seconds since the Epoch, from DTa.
```
@ -2050,19 +2050,19 @@ from threading import Thread, RLock, Semaphore, Event, Barrier
### Thread
```python
<Thread> = Thread(target=<function>) # Use `args=<collection>` to set arguments.
<Thread>.start() # Starts the thread.
<bool> = <Thread>.is_alive() # Checks if thread has finished executing.
<Thread>.join() # Waits for thread to finish.
<Thread> = Thread(target=<function>) # Use `args=<collection>` to set arguments.
<Thread>.start() # Starts the thread.
<bool> = <Thread>.is_alive() # Checks if thread has finished executing.
<Thread>.join() # Waits for thread to finish.
```
* **Use `'kwargs=<dict>'` to pass keyword arguments to the function.**
* **Use `'daemon=True'`, or the program will not be able to exit while the thread is alive.**
### Lock
```python
<lock> = RLock() # Lock that can only be released by the owner.
<lock>.acquire() # Waits for lock to be available.
<lock>.release() # Makes lock available again.
<lock> = RLock() # Lock that can only be released by the owner.
<lock>.acquire() # Waits for lock to be available.
<lock>.release() # Makes lock available again.
```
#### Or:
@ -2074,9 +2074,9 @@ with lock:
### Semaphore, Event, Barrier
```python
<Semaphore> = Semaphore(value=1) # Lock that can be acquired by 'value' threads.
<Event> = Event() # Method wait() blocks until set() is called.
<Barrier> = Barrier(n_times) # Method wait() blocks until it's called n_times.
<Semaphore> = Semaphore(value=1) # Lock that can be acquired by 'value' threads.
<Event> = Event() # Method wait() blocks until set() is called.
<Barrier> = Barrier(n_times) # Wait() blocks until it's called n_times.
```
### Thread Pool Executor
@ -2086,15 +2086,15 @@ from concurrent.futures import ThreadPoolExecutor
```
```python
<Exec> = ThreadPoolExecutor([max_workers]) # Use max_workers to limit the number of threads.
<Exec>.shutdown(wait=True) # Or: `with ThreadPoolExecutor() as executor: …`
<Exec> = ThreadPoolExecutor(max_workers=None) # Or: `with ThreadPoolExecutor() as <name>: …`
<Exec>.shutdown(wait=True) # Cleans-up the resources associated with Exec.
```
```python
<iter> = <Exec>.map(<func>, <args_1>, ...) # A multithreaded and non-lazy map().
<Futr> = <Exec>.submit(<func>, <arg_1>, ...) # Starts a thread and returns its Future object.
<bool> = <Futr>.done() # Checks if thread has finished executing.
<obj> = <Futr>.result() # Waits for thread to finish and returns result.
<iter> = <Exec>.map(<func>, <args_1>, ...) # A multithreaded and non-lazy map().
<Futr> = <Exec>.submit(<func>, <arg_1>, ...) # Starts a thread and returns its Future object.
<bool> = <Futr>.done() # Checks if the thread has finished executing.
<obj> = <Futr>.result() # Waits for thread to finish and returns result.
```
### Queue
@ -2105,10 +2105,10 @@ from queue import Queue
```
```python
<Queue>.put(<el>) # Blocks until queue stops being full.
<Queue>.put_nowait(<el>) # Raises queue.Full exception if full.
<el> = <Queue>.get() # Blocks until queue stops being empty.
<el> = <Queue>.get_nowait() # Raises queue.Empty exception if empty.
<Queue>.put(<el>) # Blocks until queue stops being full.
<Queue>.put_nowait(<el>) # Raises queue.Full exception if full.
<el> = <Queue>.get() # Blocks until queue stops being empty.
<el> = <Queue>.get_nowait() # Raises queue.Empty exception if empty.
```
@ -2158,7 +2158,7 @@ delattr(<object>, '<attr_name>') # Equivalent to `del <object>.<attr_n
### Parameters
```python
from inspect import signature
<Sig> = signature(<function>) # Signature object of the function.
<Sig> = signature(<function>) # Function's Signature object.
<dict> = <Sig>.parameters # Dict of function's Parameter objects.
<str> = <Param>.name # Parameter's name.
<memb> = <Param>.kind # Member of ParameterKind enum.

56
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@ -615,9 +615,9 @@ to_exclusive = &lt;range&gt;.stop
<div><h3 id="random">Random</h3><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> random <span class="hljs-keyword">import</span> random, randint, choice, shuffle, gauss, seed
&lt;float&gt; = random()
&lt;int&gt; = randint(from_inclusive, to_inclusive)
&lt;el&gt; = choice(&lt;list&gt;)
&lt;float&gt; = random() <span class="hljs-comment"># A float inside [0, 1).</span>
&lt;int&gt; = randint(from_inc, to_inc) <span class="hljs-comment"># An int inside [from_inc, to_inc].</span>
&lt;el&gt; = choice(&lt;list&gt;) <span class="hljs-comment"># Keeps the list intact.</span>
</code></pre></div>
<div><h3 id="binhex">Bin, Hex</h3><pre><code class="python language-python hljs">&lt;int&gt; = ±<span class="hljs-number">0</span>b&lt;bin&gt; <span class="hljs-comment"># Or: ±0x&lt;hex&gt;</span>
@ -694,13 +694,13 @@ to_exclusive = &lt;range&gt;.stop
<div><h3 id="timezone">Timezone</h3><pre><code class="python language-python apache hljs">&lt;tzinfo&gt; = UTC <span class="hljs-comment"># UTC timezone. London without DST.</span>
&lt;tzinfo&gt; = tzlocal() <span class="hljs-comment"># Local timezone. Also gettz().</span>
&lt;tzinfo&gt; = gettz(<span class="hljs-string">'&lt;Continent&gt;/&lt;City&gt;'</span>) <span class="hljs-comment"># 'Continent/City_Name' timezone or None.</span>
&lt;DTa&gt; = &lt;DT&gt;.astimezone(&lt;tzinfo&gt;) <span class="hljs-comment"># Datetime, converted to passed timezone.</span>
&lt;Ta/DTa&gt; = &lt;T/DT&gt;.replace(tzinfo=&lt;tzinfo&gt;) <span class="hljs-comment"># Unconverted object with new timezone.</span>
&lt;DTa&gt; = &lt;DT&gt;.astimezone(&lt;tzinfo&gt;) <span class="hljs-comment"># Datetime, converted to the passed timezone.</span>
&lt;Ta/DTa&gt; = &lt;T/DT&gt;.replace(tzinfo=&lt;tzinfo&gt;) <span class="hljs-comment"># Unconverted object with a new timezone.</span>
</code></pre></div>
<div><h3 id="encode">Encode</h3><pre><code class="python language-python apache hljs">&lt;D/T/DT&gt; = D/T/DT.fromisoformat(<span class="hljs-string">'&lt;iso&gt;'</span>) <span class="hljs-comment"># Object from ISO string. Raises ValueError.</span>
&lt;DT&gt; = DT.strptime(&lt;str&gt;, <span class="hljs-string">'&lt;format&gt;'</span>) <span class="hljs-comment"># Datetime from str, according to format.</span>
&lt;D/DTn&gt; = D/DT.fromordinal(&lt;int&gt;) <span class="hljs-comment"># D/DTn from days since Christ, at midnight.</span>
&lt;D/DTn&gt; = D/DT.fromordinal(&lt;int&gt;) <span class="hljs-comment"># D/DTn from days since the Gregorian NYE 1.</span>
&lt;DTn&gt; = DT.fromtimestamp(&lt;real&gt;) <span class="hljs-comment"># Local time DTn from seconds since the Epoch.</span>
&lt;DTa&gt; = DT.fromtimestamp(&lt;real&gt;, &lt;tz.&gt;) <span class="hljs-comment"># Aware datetime from seconds since the Epoch.</span>
</code></pre></div>
@ -711,7 +711,7 @@ to_exclusive = &lt;range&gt;.stop
</ul>
<div><h3 id="decode">Decode</h3><pre><code class="python language-python hljs">&lt;str&gt; = &lt;D/T/DT&gt;.isoformat(sep=<span class="hljs-string">'T'</span>) <span class="hljs-comment"># Also timespec='auto/hours/minutes/seconds'.</span>
&lt;str&gt; = &lt;D/T/DT&gt;.strftime(<span class="hljs-string">'&lt;format&gt;'</span>) <span class="hljs-comment"># Custom string representation.</span>
&lt;int&gt; = &lt;D/DT&gt;.toordinal() <span class="hljs-comment"># Days since Christ, ignoring time and tz.</span>
&lt;int&gt; = &lt;D/DT&gt;.toordinal() <span class="hljs-comment"># Days since Gregorian NYE 1, ignoring time and tz.</span>
&lt;float&gt; = &lt;DTn&gt;.timestamp() <span class="hljs-comment"># Seconds since the Epoch, from DTn in local tz.</span>
&lt;float&gt; = &lt;DTa&gt;.timestamp() <span class="hljs-comment"># Seconds since the Epoch, from DTa.</span>
</code></pre></div>
@ -1835,19 +1835,19 @@ CompletedProcess(args=[<span class="hljs-string">'bc'</span>, <span class="hljs-
</code></pre></div>
<div><h3 id="thread">Thread</h3><pre><code class="python language-python hljs">&lt;Thread&gt; = Thread(target=&lt;function&gt;) <span class="hljs-comment"># Use `args=&lt;collection&gt;` to set arguments.</span>
&lt;Thread&gt;.start() <span class="hljs-comment"># Starts the thread.</span>
&lt;bool&gt; = &lt;Thread&gt;.is_alive() <span class="hljs-comment"># Checks if thread has finished executing.</span>
&lt;Thread&gt;.join() <span class="hljs-comment"># Waits for thread to finish.</span>
<div><h3 id="thread">Thread</h3><pre><code class="python language-python hljs">&lt;Thread&gt; = Thread(target=&lt;function&gt;) <span class="hljs-comment"># Use `args=&lt;collection&gt;` to set arguments.</span>
&lt;Thread&gt;.start() <span class="hljs-comment"># Starts the thread.</span>
&lt;bool&gt; = &lt;Thread&gt;.is_alive() <span class="hljs-comment"># Checks if thread has finished executing.</span>
&lt;Thread&gt;.join() <span class="hljs-comment"># Waits for thread to finish.</span>
</code></pre></div>
<ul>
<li><strong>Use <code class="python hljs"><span class="hljs-string">'kwargs=&lt;dict&gt;'</span></code> to pass keyword arguments to the function.</strong></li>
<li><strong>Use <code class="python hljs"><span class="hljs-string">'daemon=True'</span></code>, or the program will not be able to exit while the thread is alive.</strong></li>
</ul>
<div><h3 id="lock">Lock</h3><pre><code class="python language-python hljs">&lt;lock&gt; = RLock() <span class="hljs-comment"># Lock that can only be released by the owner.</span>
&lt;lock&gt;.acquire() <span class="hljs-comment"># Waits for lock to be available.</span>
&lt;lock&gt;.release() <span class="hljs-comment"># Makes lock available again.</span>
<div><h3 id="lock">Lock</h3><pre><code class="python language-python hljs">&lt;lock&gt; = RLock() <span class="hljs-comment"># Lock that can only be released by the owner.</span>
&lt;lock&gt;.acquire() <span class="hljs-comment"># Waits for lock to be available.</span>
&lt;lock&gt;.release() <span class="hljs-comment"># Makes lock available again.</span>
</code></pre></div>
<div><h4 id="or-1">Or:</h4><pre><code class="python language-python hljs">lock = RLock()
@ -1855,32 +1855,32 @@ CompletedProcess(args=[<span class="hljs-string">'bc'</span>, <span class="hljs-
...
</code></pre></div>
<div><h3 id="semaphoreeventbarrier">Semaphore, Event, Barrier</h3><pre><code class="python language-python hljs">&lt;Semaphore&gt; = Semaphore(value=<span class="hljs-number">1</span>) <span class="hljs-comment"># Lock that can be acquired by 'value' threads.</span>
&lt;Event&gt; = Event() <span class="hljs-comment"># Method wait() blocks until set() is called.</span>
&lt;Barrier&gt; = Barrier(n_times) <span class="hljs-comment"># Method wait() blocks until it's called n_times.</span>
<div><h3 id="semaphoreeventbarrier">Semaphore, Event, Barrier</h3><pre><code class="python language-python hljs">&lt;Semaphore&gt; = Semaphore(value=<span class="hljs-number">1</span>) <span class="hljs-comment"># Lock that can be acquired by 'value' threads.</span>
&lt;Event&gt; = Event() <span class="hljs-comment"># Method wait() blocks until set() is called.</span>
&lt;Barrier&gt; = Barrier(n_times) <span class="hljs-comment"># Wait() blocks until it's called n_times.</span>
</code></pre></div>
<div><h3 id="threadpoolexecutor">Thread Pool Executor</h3><p><strong>Object that manages thread execution.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> concurrent.futures <span class="hljs-keyword">import</span> ThreadPoolExecutor
</code></pre></div>
<pre><code class="python language-python hljs">&lt;Exec&gt; = ThreadPoolExecutor([max_workers]) <span class="hljs-comment"># Use max_workers to limit the number of threads.</span>
&lt;Exec&gt;.shutdown(wait=<span class="hljs-keyword">True</span>) <span class="hljs-comment"># Or: `with ThreadPoolExecutor() as executor: …`</span>
<pre><code class="python language-python hljs">&lt;Exec&gt; = ThreadPoolExecutor(max_workers=<span class="hljs-keyword">None</span>) <span class="hljs-comment"># Or: `with ThreadPoolExecutor() as &lt;name&gt;: …`</span>
&lt;Exec&gt;.shutdown(wait=<span class="hljs-keyword">True</span>) <span class="hljs-comment"># Cleans-up the resources associated with Exec.</span>
</code></pre>
<pre><code class="python language-python hljs">&lt;iter&gt; = &lt;Exec&gt;.map(&lt;func&gt;, &lt;args_1&gt;, ...) <span class="hljs-comment"># A multithreaded and non-lazy map().</span>
&lt;Futr&gt; = &lt;Exec&gt;.submit(&lt;func&gt;, &lt;arg_1&gt;, ...) <span class="hljs-comment"># Starts a thread and returns its Future object.</span>
&lt;bool&gt; = &lt;Futr&gt;.done() <span class="hljs-comment"># Checks if thread has finished executing.</span>
&lt;obj&gt; = &lt;Futr&gt;.result() <span class="hljs-comment"># Waits for thread to finish and returns result.</span>
<pre><code class="python language-python hljs">&lt;iter&gt; = &lt;Exec&gt;.map(&lt;func&gt;, &lt;args_1&gt;, ...) <span class="hljs-comment"># A multithreaded and non-lazy map().</span>
&lt;Futr&gt; = &lt;Exec&gt;.submit(&lt;func&gt;, &lt;arg_1&gt;, ...) <span class="hljs-comment"># Starts a thread and returns its Future object.</span>
&lt;bool&gt; = &lt;Futr&gt;.done() <span class="hljs-comment"># Checks if the thread has finished executing.</span>
&lt;obj&gt; = &lt;Futr&gt;.result() <span class="hljs-comment"># Waits for thread to finish and returns result.</span>
</code></pre>
<div><h3 id="queue">Queue</h3><p><strong>A thread-safe FIFO queue. For LIFO queue use LifoQueue.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> queue <span class="hljs-keyword">import</span> Queue
&lt;Queue&gt; = Queue(maxsize=<span class="hljs-number">0</span>)
</code></pre></div>
<pre><code class="python language-python hljs">&lt;Queue&gt;.put(&lt;el&gt;) <span class="hljs-comment"># Blocks until queue stops being full.</span>
&lt;Queue&gt;.put_nowait(&lt;el&gt;) <span class="hljs-comment"># Raises queue.Full exception if full.</span>
&lt;el&gt; = &lt;Queue&gt;.get() <span class="hljs-comment"># Blocks until queue stops being empty.</span>
&lt;el&gt; = &lt;Queue&gt;.get_nowait() <span class="hljs-comment"># Raises queue.Empty exception if empty.</span>
<pre><code class="python language-python hljs">&lt;Queue&gt;.put(&lt;el&gt;) <span class="hljs-comment"># Blocks until queue stops being full.</span>
&lt;Queue&gt;.put_nowait(&lt;el&gt;) <span class="hljs-comment"># Raises queue.Full exception if full.</span>
&lt;el&gt; = &lt;Queue&gt;.get() <span class="hljs-comment"># Blocks until queue stops being empty.</span>
&lt;el&gt; = &lt;Queue&gt;.get_nowait() <span class="hljs-comment"># Raises queue.Empty exception if empty.</span>
</code></pre>
<div><h2 id="operator"><a href="#operator" name="operator">#</a>Operator</h2><p><strong>Module of functions that provide the functionality of operators.</strong></p><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> operator <span class="hljs-keyword">import</span> add, sub, mul, truediv, floordiv, mod, pow, neg, abs
<span class="hljs-keyword">from</span> operator <span class="hljs-keyword">import</span> eq, ne, lt, le, gt, ge
@ -1914,7 +1914,7 @@ delattr(&lt;object&gt;, <span class="hljs-string">'&lt;attr_name&gt;'</span>)
</code></pre></div>
<div><h3 id="parameters-1">Parameters</h3><pre><code class="python language-python hljs"><span class="hljs-keyword">from</span> inspect <span class="hljs-keyword">import</span> signature
&lt;Sig&gt; = signature(&lt;function&gt;) <span class="hljs-comment"># Signature object of the function.</span>
&lt;Sig&gt; = signature(&lt;function&gt;) <span class="hljs-comment"># Function's Signature object.</span>
&lt;dict&gt; = &lt;Sig&gt;.parameters <span class="hljs-comment"># Dict of function's Parameter objects.</span>
&lt;str&gt; = &lt;Param&gt;.name <span class="hljs-comment"># Parameter's name.</span>
&lt;memb&gt; = &lt;Param&gt;.kind <span class="hljs-comment"># Member of ParameterKind enum.</span>

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