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SQL to find the number of distinct values in a column
...quency:
SELECT column_name, COUNT(*) FROM table_name GROUP BY column_name ORDER BY 2 DESC;
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How to make junior programmers write tests? [closed]
...ng over the shoulder of the driver and pointing out suggestions, mistakes, etc as they go). It may seem like a waste of resources, but you will find:
That these guys together can produce code plenty fast and of higher quality.
If your junior guy learns enough to "get it" with a senior guy directi...
Razor comment syntax
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Adding an arbitrary line to a matplotlib plot in ipython notebook
...linewidth=2)
(of course you can choose the color, line width, line style, etc.)
From your example:
import numpy as np
import matplotlib.pyplot as plt
np.random.seed(5)
x = np.arange(1, 101)
y = 20 + 3 * x + np.random.normal(0, 60, 100)
plt.plot(x, y, "o")
# draw vertical line from (70,100) to ...
Best ways to teach a beginner to program? [closed]
...eedback, and you can demostrate loops, variables, functions, conditionals, etc. This page provides an excellent tutorial.
After Logo, move to Python or Ruby. I recommend Python, as it's based on ABC, which was invented for the purpose of teaching programming.
When teaching programming, I must se...
Find the files that have been changed in last 24 hours
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Limit text length to n lines using CSS
... and bottom for the psudo class are px based on various factors, font-size etc... Tweak for your own needs. */
<div class="text ellipsis">
<span class="text-concat">
Lorem ipsum dolor sit amet, nibh eleifend cu his, porro fugit mandamus no mea. Sit tale facete voluptatum ea, ad sumo...
Why do we use Base64?
...y want to communicate with more rich forms data such as text or images. In order to transfer this data between computers it first has to be encoded into 0s and 1s, sent, then decoded again. To take text as an example - there are many different ways to perform this encoding. It would be much simpler ...
Why is the Java main method static?
...when we have to bridge the virtual machine world, and the world of C, C++, etc... The reverse is also true - it is not possible (at least to my knowledge) to actually get a JVM running without using JNI.
Basically, java.exe is a super simple C application that parses the command line, creates a n...
How to parse a string into a nullable int
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There is no order-of-evaluation side-effect here. All steps are explicitly ordered and correct.
– Jon Hanna
Mar 22 '11 at 14:30
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