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[Tut] Python Join List [Ultimate Guide] - xSicKxBot - 06-06-2020
Python Join List [Ultimate Guide]
<div><p>In this ultimate guide, you’ll learn everything you need to know about joining list elements in Python. To give you a quick overview, let’s have a look at the following problem.</p>
<p><strong>Problem</strong>: Given a <a rel="noreferrer noopener" href="https://blog.finxter.com/python-lists/" target="_blank">list </a>of elements. How to join the elements by <a rel="noreferrer noopener" href="https://blog.finxter.com/concatenate-lists-in-python/" target="_blank">concatenating</a> all elements in the list?</p>
<p><strong>Example</strong>: You want to <a href="https://blog.finxter.com/python-list-to-string/" target="_blank" rel="noreferrer noopener">convert list</a> <code>['learn ', 'python ', 'fast']</code> to the string <code>'learn python fast'</code>. </p>
<p><strong>Quick Solution</strong>: to convert a list of strings to a string, do the following.</p>
<ul>
<li>Call the <code>''.join(list)</code> method on the empty string <code>''</code> that glues together all strings in the <code>list</code> and returns a new string. </li>
<li>The string on which you call the join method is used as a delimiter between the list elements. </li>
<li>If you don’t need a delimiter, just use the empty string <code>''</code>. </li>
</ul>
<p><strong>Code</strong>: Let’s have a look at the code.</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn ', 'python ', 'fast']
print(''.join(lst))</pre>
<p>The output is:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">learn python fast</pre>
<p>Try it yourself in our interactive Python shell:</p>
<p> <iframe src="https://repl.it/@finxter/joinpythonstringlist?lite=true" scrolling="no" allowtransparency="true" allowfullscreen="true" sandbox="allow-forms allow-pointer-lock allow-popups allow-same-origin allow-scripts allow-modals" width="100%" height="400px" frameborder="no"></iframe> </p>
<p>You can also use another delimiter string, for example, the comma:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn' , 'python', 'fast']
print(','.join(lst))
# learn,python,fast</pre>
<h2>Python Join List Syntax</h2>
<h2>Python Join List of Lists</h2>
<h2>Python Join List of Strings With Comma</h2>
<p><strong>Problem</strong>: Given a list of strings. How to convert the list to a string by <a rel="noreferrer noopener" href="https://blog.finxter.com/concatenate-lists-in-python/" target="_blank">concatenating</a> all strings in the list—using a comma as the delimiter between the list elements?</p>
<p><strong>Example</strong>: You want to convert list <code>['learn', 'python', 'fast']</code> to the string <code>'learn,python,fast'</code>. </p>
<p><strong>Solution</strong>: to convert a list of strings to a string, call the <code>','.join(list)</code> method on the delimiter string <code>','</code> that glues together all strings in the <code>list</code> and returns a new string. </p>
<p><strong>Code</strong>: Let’s have a look at the code.</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn', 'python', 'fast']
print(','.join(lst))</pre>
<p>The output is:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">learn,python,fast</pre>
<h2>Python Join List of Strings With Newline</h2>
<p><strong>Problem</strong>: Given a list of strings. How to convert the list to a string by <a rel="noreferrer noopener" href="https://blog.finxter.com/concatenate-lists-in-python/" target="_blank">concatenating</a> all strings in the list—using a newline character as the delimiter between the list elements?</p>
<p><strong>Example</strong>: You want to convert list <code>['learn', 'python', 'fast']</code> to the string <code>'learn\npython\nfast'</code> or as a multiline string:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">'''learn
python
fast'''</pre>
<p><strong>Solution</strong>: to convert a list of strings to a string, call the <code>'\n'.join(list)</code> method on the newline character <code>'\n'</code> that glues together all strings in the <code>list</code> and returns a new string. </p>
<p><strong>Code</strong>: Let’s have a look at the code.</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn', 'python', 'fast']
print('\n'.join(lst))</pre>
<p>The output is:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">learn
python
fast</pre>
<h2>Python Join List of Strings With Space</h2>
<p><strong>Problem</strong>: Given a list of strings. How to convert the list to a string by <a rel="noreferrer noopener" href="https://blog.finxter.com/concatenate-lists-in-python/" target="_blank">concatenating</a> all strings in the list—using a space as the delimiter between the list elements?</p>
<p><strong>Example</strong>: You want to convert list <code>['learn', 'python', 'fast']</code> to the string <code>'learn python fast'</code>. (Note the empty spaces between the terms.)</p>
<p><strong>Solution</strong>: to convert a list of strings to a string, call the <code>' '.join(list)</code> method on the string <code>' '</code> (space character) that glues together all strings in the <code>list</code> and returns a new string. </p>
<p><strong>Code</strong>: Let’s have a look at the code.</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn', 'python', 'fast']
print(' '.join(lst))</pre>
<p>The output is:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">learn python fast</pre>
<h2>Python Join List With Single and Double Quotes</h2>
<p><strong>Problem</strong>: Given a list of strings. How to convert the list to a string by <a rel="noreferrer noopener" href="https://blog.finxter.com/concatenate-lists-in-python/" target="_blank">concatenating</a> all strings in the list—using a comma character followed by an empty space as the delimiter between the list elements? Additionally, you want to wrap each string in double quotes.</p>
<p><strong>Example</strong>: You want to convert list <code>['learn', 'python', 'fast']</code> to the string <code>'"learn", "python", "fast"'</code> :</p>
<p><strong>Solution</strong>: to convert a list of strings to a string, call the <code>', '.join('"' + x + '"' for x in lst)</code> method on the delimiter string <code>', '</code> that glues together all strings in the <code>list</code> and returns a new string. You use a generator expression to modify each element of the original element so that it is enclosed by the double quote <code>"</code> chararacter. </p>
<p><strong>Code</strong>: Let’s have a look at the code.</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = ['learn', 'python', 'fast']
print(', '.join('"' + x + '"' for x in lst))
</pre>
<p>The output is:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">"learn", "python", "fast"</pre>
<h2>Python Join List With None</h2>
<h2>Python Join List With Tabs</h2>
<h2>Python Join List With Delimiter</h2>
<h2>Python Join List With Carriage Return</h2>
<h2>Python Join List with Underscore</h2>
<h2>Python Join List of Integers</h2>
<p><strong>Problem</strong>: You want to convert a list into a string but the list contains integer values.</p>
<p><strong>Example</strong>: Convert the list <code>[1, 2, 3]</code> to a string <code>'123'</code>.</p>
<p><strong>Solution</strong>: Use the join method in combination with a <a href="https://blog.finxter.com/list-comprehension/" target="_blank" rel="noreferrer noopener">generator expression</a> to convert the list of integers to a single string value: </p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = [1, 2, 3]
print(''.join(str(x) for x in lst))
# 123</pre>
<p>The generator expression converts each element in the list to a string. You can then combine the string elements using the join method of the string object. </p>
<p>If you miss the conversion from integer to string, you get the following <code>TypeError</code>:</p>
<pre class="EnlighterJSRAW" data-enlighter-language="generic" data-enlighter-theme="" data-enlighter-highlight="" data-enlighter-linenumbers="" data-enlighter-lineoffset="" data-enlighter-title="" data-enlighter-group="">lst = [1, 2, 3]
print(''.join(lst)) '''
Traceback (most recent call last): File "C:\Users\xcent\Desktop\code.py", line 2, in <module> print(''.join(lst))
TypeError: sequence item 0: expected str instance, int found '''</pre>
<h2>Python Join List of Floats</h2>
<h2>Python Join List of Booleans</h2>
<h2>Python Join List of Tuples</h2>
<h2>Python Join List of Sets</h2>
<h2>Python Join List of Bytes</h2>
<h2>Python Join List of Dictionaries</h2>
<h2>Python Join List Except First or Last Element</h2>
<h2>Python Join List Remove Duplicates</h2>
<h2>Python Join List Reverse</h2>
<h2>Python Join List Range</h2>
<h2>Python Join List By Row</h2>
<h2>Python Join List of Unicode Strings</h2>
<h2>Python Join List in Pairs</h2>
<h2>Python Join List as Path</h2>
<h2>Python Join List Slice</h2>
<h2>Python Join Specific List Elements</h2>
<h2>Python Join List of DataFrames</h2>
<h2>Python Join List Comprehension</h2>
<h2>Python Join List Map</h2>
<h2>Python Join List Columns</h2>
</p>
<h2>Where to Go From Here?</h2>
<p>Enough theory, let’s get some practice!</p>
<p>To become successful in coding, you need to get out there and solve real problems for real people. That’s how you can become a six-figure earner easily. And that’s how you polish the skills you really need in practice. After all, what’s the use of learning theory that nobody ever needs?</p>
<p><strong>Practice projects is how you sharpen your saw in coding!</strong></p>
<p>Do you want to become a code master by focusing on practical code projects that actually earn you money and solve problems for people?</p>
<p>Then become a Python freelance developer! It’s the best way of approaching the task of improving your Python skills—even if you are a complete beginner.</p>
<p>Join my free webinar <a rel="noreferrer noopener" href="https://blog.finxter.com/webinar-freelancer/" target="_blank">“How to Build Your High-Income Skill Python”</a> and watch how I grew my coding business online and how you can, too—from the comfort of your own home.</p>
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</div>
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