This section of our beginning python training class always stumps students.  Firstly, because they need to know the difference between a function and a method.  Secondly, they need to understand object oriented programming concepts.  Thirdly, they need to realize that python has three types of methods.  Then they need to know how to use each method, which means they need to know the purpose of each method type.  Then they have to understand mutable versus non-mutable types.  The list goes on.  As part of our python tutorial, I hope to shed some light on this confusing topic.

To begin, the difference between a function and a method in python is that a method is defined within a class.  Here is an illustration:

#function

	def greeting():
	                print "Hello, I hope you're having a great day!"

	class HSGPrinter(object):
	                #method
	                def greeting(self): 
	                                print "Hello, I hope you're having a great day!"

As should be obvious, the second definition of greeting is encapsulated within the HSGPrinter class and is , therefore, refered to as a method.

The astute reader will notice that the greeting method contains one parameter named self.  For those who know C++ , Java or C#, self is equivalent to this i.e. it is a reference to the invoking object:

When it comes to running a start up, leaders need to make sure that their key players are motivated. This has been seen with many companies. Back in the 1970's it was found with the inspiration and diligence of the late Daniel Nigro when he formed Kleer-Fax. More recently it was seen in David Khasidy, the founder and recently retired president of SunRay Power Management, the most dynamic green energy leader in the US today.

The question is, what is it that great leaders like David Khasidy and Daniel Nigro do that make the difference? How do the most vulnerable companies (start ups) break the mold and become a part of our everyday lives?

It starts with their mission and vision.

Create a Strong Mission and Vision

There are many reasons why start ups fail. For one, they usually lack the capital to last through the lean times. Secondly, they often don't have the tolerance for setbacks that occur. Lastly, they do not have a long-term plan, also called a mission.

When a business has a strong mission, the team knows it and their focus toward their work and service to others within and without the company reflects that. To complement that, the shorter term vision of the company needs to be present as well.

This can even be seen in sole proprietorships with no employees, such as when Brian Pascale started his law practice. His vision was to find justice for his clients while his mission was to build upon a career that had already set precedents in the area of tort law.

As his practice has grown, new staff members can sense the vision and mission he exudes.

Encourage Ownership of Projects and Processes

Start ups need to inspire and motivate their employees because they need to know that they are not only a part of something important, but that their contributions mean something.

What won't happen if they are not there? What contribution do they make, and what are the consequences of them not fulfilling their part of the work?

By encouraging ownership in projects, team members can find that the work they are doing is not only important for the organization, but that they are going to be a big part of what makes it happen. The alternative is that they feel replaceable.

Offer Incentives That Keep the Company Competitive

When team members embrace the mission and vision of the company, and then take ownership for the company's success, they are going to need to be justly rewarded.

This could include flexible schedules (for those who don't need a stringent one), use of an account at a nearby takeout place, or even the potential for ownership as a result of a vesting program.

The incentive everyone is looking for more immediately, though, is cash. When the company takes in more revenue as a result of the efforts of those on the team, rewarding them can go a long way not only in making them feel appreciated, but in encouraging them to bring in more business.

Members of a start up team are usually very talented, and commonly underpaid. However, if they believe they are going somewhere, it will make a big difference.

Related:

Good non-programmer jobs for people with software developer experience

The original article was posted by Michael Veksler on Quora

A very well known fact is that code is written once, but it is read many times. This means that a good developer, in any language, writes understandable code. Writing understandable code is not always easy, and takes practice. The difficult part, is that you read what you have just written and it makes perfect sense to you, but a year later you curse the idiot who wrote that code, without realizing it was you.

The best way to learn how to write readable code, is to collaborate with others. Other people will spot badly written code, faster than the author. There are plenty of open source projects, which you can start working on and learn from more experienced programmers.

Readability is a tricky thing, and involves several aspects:

1. Never surprise the reader of your code, even if it will be you a year from now. For example, don’t call a function max() when sometimes it returns the minimum().
2. Be consistent, and use the same conventions throughout your code. Not only the same naming conventions, and the same indentation, but also the same semantics. If, for example, most of your functions return a negative value for failure and a positive for success, then avoid writing functions that return false on failure.
3. Write short functions, so that they fit your screen. I hate strict rules, since there are always exceptions, but from my experience you can almost always write functions short enough to fit your screen. Throughout my carrier I had only a few cases when writing short function was either impossible, or resulted in much worse code.
4. Use descriptive names, unless this is one of those standard names, such as i or it in a loop. Don’t make the name too long, on one hand, but don’t make it cryptic on the other.
5. Define function names by what they do, not by what they are used for or how they are implemented. If you name functions by what they do, then code will be much more readable, and much more reusable.
6. Avoid global state as much as you can. Global variables, and sometimes attributes in an object, are difficult to reason about. It is difficult to understand why such global state changes, when it does, and requires a lot of debugging.
7. As Donald Knuth wrote in one of his papers: “Early optimization is the root of all evil”. Meaning, write for readability first, optimize later.
8. The opposite of the previous rule: if you have an alternative which has similar readability, but lower complexity, use it. Also, if you have a polynomial alternative to your exponential algorithm (when N > 10), you should use that.

Use standard library whenever it makes your code shorter; don’t implement everything yourself. External libraries are more problematic, and are both good and bad. With external libraries, such as boost, you can save a lot of work. You should really learn boost, with the added benefit that the c++ standard gets more and more form boost. The negative with boost is that it changes over time, and code that works today may break tomorrow. Also, if you try to combine a third-party library, which uses a specific version of boost, it may break with your current version of boost. This does not happen often, but it may.

Don’t blindly use C++ standard library without understanding what it does - learn it. You look at std::vector::push_back() documentation at it tells you that its complexity is O(1), amortized. What does that mean? How does it work? What are benefits and what are the costs? Same with std::map, and with std::unordered_map. Knowing the difference between these two maps, you’d know when to use each one of them.

Never call new or delete directly, use std::make_unique and [cost c++]std::make_shared[/code] instead. Try to implement usique_ptr, shared_ptr, weak_ptr yourself, in order to understand what they actually do. People do dumb things with these types, since they don’t understand what these pointers are.

Every time you look at a new class or function, in boost or in std, ask yourself “why is it done this way and not another?”. It will help you understand trade-offs in software development, and will help you use the right tool for your job. Don’t be afraid to peek into the source of boost and the std, and try to understand how it works. It will not be easy, at first, but you will learn a lot.

Know what complexity is, and how to calculate it. Avoid exponential and cubic complexity, unless you know your N is very low, and will always stay low.

Learn data-structures and algorithms, and know them. Many people think that it is simply a wasted time, since all data-structures are implemented in standard libraries, but this is not as simple as that. By understanding data-structures, you’d find it easier to pick the right library. Also, believe it or now, after 25 years since I learned data-structures, I still use this knowledge. Half a year ago I had to implemented a hash table, since I needed fast serialization capability which the available libraries did not provide. Now I am writing some sort of interval-btree, since using std::map, for the same purpose, turned up to be very very slow, and the performance bottleneck of my code.

Notice that you can’t just find interval-btree on Wikipedia, or stack-overflow. The closest thing you can find is Interval tree, but it has some performance drawbacks. So how can you implement an interval-btree, unless you know what a btree is and what an interval-tree is? I strongly suggest, again, that you learn and remember data-structures.

These are the most important things, which will make you a better programmer. The other things will follow.