Edited, memorised or added to reading list

on 03-Jun-2017 (Sat)

Do you want BuboFlash to help you learning these things? Click here to log in or create user.

#python #scip
data is stuff that we want to manipulate, and functions describe the rules for manipulating the data

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
d means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will discover that they are really not so distinct.) Informally, <span>data is stuff that we want to manipulate, and functions describe the rules for manipulating the data. Thus, any powerful programming language should be able to describe primitive data and primitive functions, as well as have some methods for combining and abstracting both functions and




#python #scip
One kind of primitive expression is a number. More precisely, the expression that you type consists of the numerals that represent the number in base 10

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
terpreter in the previous section, we now start anew, methodically developing the Python language element by element. Be patient if the examples seem simplistic — more exciting material is soon to come. We begin with primitive expressions. <span>One kind of primitive expression is a number. More precisely, the expression that you type consists of the numerals that represent the number in base 10. >>> 42 42 Expressions representing numbers may be combined with mathematical operators to form a compound expression, which the interpreter will evaluate: >>>




#python #scip
The most important kind of compound expression is a call expression, which applies a function to some arguments.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
ways to form compound expressions. Rather than attempt to enumerate them all immediately, we will introduce new expression forms as we go, along with the language features that they support. 1.2.2 Call Expressions Video: Show Hide <span>The most important kind of compound expression is a call expression, which applies a function to some arguments. Recall from algebra that the mathematical notion of a function is a mapping from some input arguments to an output value. For instance, the max function maps its inputs to a single ou




#python #scip
the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
s inputs to a single output, which is the largest of the inputs. The way in which Python expresses function application is the same as in conventional mathematics. >>> max(7.5, 9.5) 9.5 This call expression has subexpressions: <span>the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions. The operator specifies a function. When this call expression is evaluated, we say that the function max is called with arguments 7.5 and 9.5, and returns a value of 9.5. The




#python #scip

The operator specifies a function. When this call expression is evaluated, we say that the function max is called with arguments 7.5 and 9.5, and returns a value of 9.5.

The order of the arguments in a call expression matters. For instance, the function pow raises its first argument to the power of its second argument.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
he same as in conventional mathematics. >>> max(7.5, 9.5) 9.5 This call expression has subexpressions: the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions. <span>The operator specifies a function. When this call expression is evaluated, we say that the function max is called with arguments 7.5 and 9.5, and returns a value of 9.5. The order of the arguments in a call expression matters. For instance, the function pow raises its first argument to the power of its second argument. >>> pow(100, 2) 10000 >>> pow(2, 100) 1267650600228229401496703205376 Function notation has three principal advantages over the mathematical convention of infix




#python #scip

Function notation has three principal advantages over the mathematical convention of infix notation. First, functions may take an arbitrary number of arguments:

 >>> max ( 1 , - 2 , 3 , - 4 ) 3 

No ambiguity can arise, because the function name always precedes its arguments.

Second, function notation extends in a straightforward way to nested expressions, where the elements are themselves compound expressions. In nested call expressions, unlike compound infix expressions, the structure of the nesting is entirely explicit in the parentheses.

 >>> max ( min ( 1 , - 2 ), min ( pow ( 3 , 5 ), - 4 )) -2 

There is no limit (in principle) to the depth of such nesting and to the overall complexity of the expressions that the Python interpreter can evaluate. However, humans quickly get confused by multi-level nesting. An important role for you as a programmer is to structure expressions so that they remain interpretable by yourself, your programming partners, and other people who may read your expressions in the future.

Third, mathematical notation has a great variety of forms: multiplication appears between terms, exponents appear as superscripts, division as a horizontal bar, and a square root as a roof with slanted siding. Some of this notation is very hard to type! However, all of this complexity can be unified via the notation of call expressions. While Python supports common mathematical operators using infix notation (like + and - ), any operator can be expressed as a function with a name.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

1.2 Elements of Programming
order of the arguments in a call expression matters. For instance, the function pow raises its first argument to the power of its second argument. >>> pow(100, 2) 10000 >>> pow(2, 100) 1267650600228229401496703205376 <span>Function notation has three principal advantages over the mathematical convention of infix notation. First, functions may take an arbitrary number of arguments: >>> max(1, -2, 3, -4) 3 No ambiguity can arise, because the function name always precedes its arguments. Second, function notation extends in a straightforward way to nested expressions, where the elements are themselves compound expressions. In nested call expressions, unlike compound infix expressions, the structure of the nesting is entirely explicit in the parentheses. >>> max(min(1, -2), min(pow(3, 5), -4)) -2 There is no limit (in principle) to the depth of such nesting and to the overall complexity of the expressions that the Python interpreter can evaluate. However, humans quickly get confused by multi-level nesting. An important role for you as a programmer is to structure expressions so that they remain interpretable by yourself, your programming partners, and other people who may read your expressions in the future. Third, mathematical notation has a great variety of forms: multiplication appears between terms, exponents appear as superscripts, division as a horizontal bar, and a square root as a roof with slanted siding. Some of this notation is very hard to type! However, all of this complexity can be unified via the notation of call expressions. While Python supports common mathematical operators using infix notation (like + and - ), any operator can be expressed as a function with a name. 1.2.3 Importing Library Functions Python defines a very large number of functions, including the operator functions mentioned in the preceding section, but does not make all o




Flashcard 1436371258636

Tags
#python #scip
Question
First, pure functions can be composed more reliably into compound call expressions.
Answer
[default - edit me]


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill
1.2 Elements of Programming
assignment statement. >>> two = print(2) 2 >>> print(two) None Pure functions are restricted in that they cannot have side effects or change behavior over time. Imposing these restrictions yields substantial benefits. <span>First, pure functions can be composed more reliably into compound call expressions. We can see in the non-pure function example above that print does not return a useful result when used in an operand expression. On the other hand, we have seen that functions such







Flashcard 1441919798540

Tags
#python #scip
Question
What is an "enviroment?"
Answer
memory that keeps track of the names, values, and bindings.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
memory that keeps track of the names, values, and bindings. This memory is called an environment.

Original toplevel document

1.2 Elements of Programming
x programs are constructed by building, step by step, computational objects of increasing complexity. The possibility of binding names to values and later retrieving those values by name means that the interpreter must maintain some sort of <span>memory that keeps track of the names, values, and bindings. This memory is called an environment. Names can also be bound to functions. For instance, the name max is bound to the max function we have been using. Functions, unlike numbers, are tricky to render as text, so Python







Flashcard 1441922157836

Tags
#python #scip
Question
If a value has been given a name, we say that the name [...] to the value
Answer
binds


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
If a value has been given a name, we say that the name binds to the value

Original toplevel document

1.2 Elements of Programming
y, this documentation will become a valuable reference source. 1.2.4 Names and the Environment Video: Show Hide A critical aspect of a programming language is the means it provides for using names to refer to computational objects. <span>If a value has been given a name, we say that the name binds to the value. In Python, we can establish new bindings using the assignment statement, which contains a name to the left of = and a value to the right: >>> radius = 10 >>> ra







Flashcard 1441923992844

Tags
#python #scip
Question
the [...] is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions.
Answer
operator


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions.

Original toplevel document

1.2 Elements of Programming
s inputs to a single output, which is the largest of the inputs. The way in which Python expresses function application is the same as in conventional mathematics. >>> max(7.5, 9.5) 9.5 This call expression has subexpressions: <span>the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions. The operator specifies a function. When this call expression is evaluated, we say that the function max is called with arguments 7.5 and 9.5, and returns a value of 9.5. The







Flashcard 1441925565708

Tags
#python #scip
Question
the operator is an expression that precedes parentheses, which enclose a comma-delimited list of [...] expressions.
Answer
operand


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions.

Original toplevel document

1.2 Elements of Programming
s inputs to a single output, which is the largest of the inputs. The way in which Python expresses function application is the same as in conventional mathematics. >>> max(7.5, 9.5) 9.5 This call expression has subexpressions: <span>the operator is an expression that precedes parentheses, which enclose a comma-delimited list of operand expressions. The operator specifies a function. When this call expression is evaluated, we say that the function max is called with arguments 7.5 and 9.5, and returns a value of 9.5. The







Flashcard 1441927138572

Tags
#python #scip
Question
The most important kind of compound expression is a [...] which applies a function to some arguments.
Answer
call expression,


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
The most important kind of compound expression is a call expression, which applies a function to some arguments.

Original toplevel document

1.2 Elements of Programming
ways to form compound expressions. Rather than attempt to enumerate them all immediately, we will introduce new expression forms as we go, along with the language features that they support. 1.2.2 Call Expressions Video: Show Hide <span>The most important kind of compound expression is a call expression, which applies a function to some arguments. Recall from algebra that the mathematical notion of a function is a mapping from some input arguments to an output value. For instance, the max function maps its inputs to a single ou







Flashcard 1441928711436

Tags
#python #scip
Question
What do primitives (expressions and elements) do? What is their purpose?
Answer
represent the simplest building blocks that the language provides,


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units.

Original toplevel document

1.2 Elements of Programming
ust be written for people to read, and only incidentally for machines to execute. When we describe a language, we should pay particular attention to the means that the language provides for combining simple ideas to form more complex ideas. <span>Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will discover that they are really not so distinct.) Informally, data is stuff that we want to manipul







Flashcard 1441931070732

Tags
#python #scip
Question
What are "means of combination?"
Answer
A term for how compound elements are built from simpler ones


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units.

Original toplevel document

1.2 Elements of Programming
ust be written for people to read, and only incidentally for machines to execute. When we describe a language, we should pay particular attention to the means that the language provides for combining simple ideas to form more complex ideas. <span>Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will discover that they are really not so distinct.) Informally, data is stuff that we want to manipul







Flashcard 1441933430028

Tags
#python #scip
Question
What is meant by "means of abstraction?"
Answer
compound elements can be named and manipulated as units.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
h mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which <span>compound elements can be named and manipulated as units.<span><body><html>

Original toplevel document

1.2 Elements of Programming
ust be written for people to read, and only incidentally for machines to execute. When we describe a language, we should pay particular attention to the means that the language provides for combining simple ideas to form more complex ideas. <span>Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will discover that they are really not so distinct.) Informally, data is stuff that we want to manipul







Flashcard 1441941032204

Tags
#python #sicp
Question
An environment in which an expression is evaluated consists of
Answer
a sequence of frames


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
An environment in which an expression is evaluated consists of a sequence of frames, depicted as boxes. Each frame contains bindings, each of which associates a name with its corresponding value. There is a single global frame. Assignment and impor

Original toplevel document

1.3 Defining New Functions
gh that the meaning of programs is non-obvious. What if a formal parameter has the same name as a built-in function? Can two functions share names without confusion? To resolve such questions, we must describe environments in more detail. <span>An environment in which an expression is evaluated consists of a sequence of frames, depicted as boxes. Each frame contains bindings, each of which associates a name with its corresponding value. There is a single global frame. Assignment and import statements add entries to the first frame of the current environment. So far, our environment consists only of the global frame. 1 from math import pi 2 tau = 2 * pi Edit code in Online Python Tutor







Flashcard 1441959906572

Tags
#python #scip
Question
What is a concurrent program?
Answer
A program in which multiple call expressions may be evaluated simultaneously.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Third, Chapter 4 will illustrate that pure functions are essential for writing concurrent programs, in which multiple call expressions may be evaluated simultaneously.

Original toplevel document

1.2 Elements of Programming
expressions. Second, pure functions tend to be simpler to test. A list of arguments will always lead to the same return value, which can be compared to the expected return value. Testing is discussed in more detail later in this chapter. <span>Third, Chapter 4 will illustrate that pure functions are essential for writing concurrent programs, in which multiple call expressions may be evaluated simultaneously. By contrast, Chapter 2 investigates a range of non-pure functions and describes their uses. For these reasons, we concentrate heavily on creating and using pure functions in the rem







Flashcard 1441963052300

Tags
#python #scip
Question
What are ways that pure functions are restricted?
Answer
Pure functions are restricted in that they cannot have side effects or change behavior over time.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Pure functions are restricted in that they cannot have side effects or change behavior over time.

Original toplevel document

1.2 Elements of Programming
this expression produces this peculiar output. Be careful with print ! The fact that it returns None means that it should not be the expression in an assignment statement. >>> two = print(2) 2 >>> print(two) None <span>Pure functions are restricted in that they cannot have side effects or change behavior over time. Imposing these restrictions yields substantial benefits. First, pure functions can be composed more reliably into compound call expressions. We can see in the non-pure function example







Flashcard 1441966722316

Tags
#python #scip
Question
Non-pure functions. In addition to returning a value, applying a non-pure function can generate [...], which make some change to the state of the interpreter or computer.
Answer
side effects


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Non-pure functions. In addition to returning a value, applying a non-pure function can generate side effects, which make some change to the state of the interpreter or computer. A common side effect is to generate additional output beyond the return value, using the print function.</spa

Original toplevel document

1.2 Elements of Programming
s output. The function abs is pure. Pure functions have the property that applying them has no effects beyond returning a value. Moreover, a pure function must always return the same value when called twice with the same arguments. <span>Non-pure functions. In addition to returning a value, applying a non-pure function can generate side effects, which make some change to the state of the interpreter or computer. A common side effect is to generate additional output beyond the return value, using the print function. >>> print(1, 2, 3) 1 2 3 While print and abs may appear to be similar in these examples, they work in fundamentally different ways. The value that print returns is







Flashcard 1447028985100

Tags
#python #scip
Question
The '=' symbol is called the [...] in Python (and many other languages)
Answer
assignment operator


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
he = symbol is called the assignment operator in Python (and many other languages)

Original toplevel document

1.2 Elements of Programming
= and a value to the right: >>> radius = 10 >>> radius 10 >>> 2 * radius 20 Names are also bound via import statements. >>> from math import pi >>> pi * 71 / 223 1.0002380197528042 T<span>he = symbol is called the assignment operator in Python (and many other languages). Assignment is our simplest means of abstraction, for it allows us to use simple names to refer to the results of compound operations, such as the area computed above. In this way, co







Flashcard 1447275924748

Tags
#sister-miriam-joseph #trivium
Question
Language can symbolize an individual or an aggregate by either a [...]
Answer
proper name or a particular or empirical description.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Language can symbolize an individual or an aggregate by either a proper name or a particular or empirical description.

Original toplevel document (pdf)

cannot see any pdfs







Flashcard 1448685735180

Tags
#3-1-profit-maximization #cfa-level-1 #economics #microeconomics #reading-15-demand-and-supply-analysis-the-firm #section-3-analysis-of-revenue-costs-and-profit #study-session-4
Question

input factors flow from sectors with [...] to sectors with [...].

Answer
economic losses


economic profit


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
sfy consumer demand. Allocates resources to their most-efficient use; input factors flow from sectors with economic losses to sectors with economic profit, where profit reflects goods most desired by society. Spurs <span>innovation and the development of new technology. Stimulates business investment and economic growth.<span><body><html>

Original toplevel document

3. ANALYSIS OF REVENUE, COSTS, AND PROFITS
Total variable cost divided by quantity; (TVC ÷ Q) Average total cost (ATC) Total cost divided by quantity; (TC ÷ Q) or (AFC + AVC) Marginal cost (MC) Change in total cost divided by change in quantity; (∆TC ÷ ∆Q) <span>3.1. Profit Maximization In free markets—and even in regulated market economies—profit maximization tends to promote economic welfare and a higher standard of living, and creates wealth for investors. Profit motivates businesses to use resources efficiently and to concentrate on activities in which they have a competitive advantage. Most economists believe that profit maximization promotes allocational efficiency—that resources flow into their highest valued uses. Overall, the functions of profit are as follows: Rewards entrepreneurs for risk taking when pursuing business ventures to satisfy consumer demand. Allocates resources to their most-efficient use; input factors flow from sectors with economic losses to sectors with economic profit, where profit reflects goods most desired by society. Spurs innovation and the development of new technology. Stimulates business investment and economic growth. There are three approaches to calculate the point of profit maximization. First, given that profit is the difference between total revenue and total costs, maximum profit occurs at the output level where this difference is the greatest. Second, maximum profit can also be calculated by comparing revenue and cost for each individual unit of output that is produced and sold. A business increases profit through greater sales as long as per-unit revenue exceeds per-unit cost on the next unit of output sold. Profit maximization takes place at the point where the last individual output unit breaks even. Beyond this point, total profit decreases because the per-unit cost is higher than the per-unit revenue from successive output units. A third approach compares the revenue generated by each resource unit with the cost of that unit. Profit contribution occurs when the revenue from an input unit exceeds its cost. The point of profit maximization is reached when resource units no longer contribute to profit. All three approaches yield the same profit-maximizing quantity of output. (These approaches will be explained in greater detail later.) Because profit is the difference between revenue and cost, an understanding of profit maximization requires that we examine both of those components. Revenue comes from the demand for the firm’s products, and cost comes from the acquisition and utilization of the firm’s inputs in the production of those products. 3.1.1. Total, Average, and Marginal Revenue This section briefly examines demand and revenue in preparation for addressing cost. Unless the firm is a pu







Flashcard 1471482563852

Tags
#python #sicp
Question

there are many kinds of sequences, but they all share common behavior. In particular,

[...]

Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element.

Answer
Length. A sequence has a finite length. An empty sequence has length 0.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
there are many kinds of sequences, but they all share common behavior. In particular, Length. A sequence has a finite length. An empty sequence has length 0. Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element.

Original toplevel document

2.3 Sequences
ful, fundamental abstraction in computer science. Sequences are not instances of a particular built-in type or abstract data representation, but instead a collection of behaviors that are shared among several different types of data. That is, <span>there are many kinds of sequences, but they all share common behavior. In particular, Length. A sequence has a finite length. An empty sequence has length 0. Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element. Python includes several native data types that are sequences, the most important of which is the list . 2.3.1 Lists A list value is a sequence that can have arbitrary lengt







Flashcard 1471484136716

Tags
#python #sicp
Question

there are many kinds of sequences, but they all share common behavior. In particular,

Length. A sequence has a finite length. An empty sequence has length 0.

[...]

Answer
Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element.


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
there are many kinds of sequences, but they all share common behavior. In particular, Length. A sequence has a finite length. An empty sequence has length 0. Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element.

Original toplevel document

2.3 Sequences
ful, fundamental abstraction in computer science. Sequences are not instances of a particular built-in type or abstract data representation, but instead a collection of behaviors that are shared among several different types of data. That is, <span>there are many kinds of sequences, but they all share common behavior. In particular, Length. A sequence has a finite length. An empty sequence has length 0. Element selection. A sequence has an element corresponding to any non-negative integer index less than its length, starting at 0 for the first element. Python includes several native data types that are sequences, the most important of which is the list . 2.3.1 Lists A list value is a sequence that can have arbitrary lengt







Flashcard 1471504846092

Tags
#python #sicp
Question
Linked lists are particularly useful when [...], a situation that arises often in recursive computations.
Answer
constructing sequences incrementally


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
Linked lists are particularly useful when constructing sequences incrementally, a situation that arises often in recursive computations.

Original toplevel document

2.3 Sequences







The system allows the instructor to enter custom wordlists (called “lexi- cal themes”) based on his or her curriculum,

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




Flashcard 1611499441420

Tags
#3-1-profit-maximization #cfa-level-1 #economics #microeconomics #reading-15-demand-and-supply-analysis-the-firm #section-3-analysis-of-revenue-costs-and-profit #study-session-4
Question

[...] reflects goods most desired by society​

Answer
Profit


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

Parent (intermediate) annotation

Open it
sfy consumer demand. Allocates resources to their most-efficient use; input factors flow from sectors with economic losses to sectors with economic profit, where profit reflects goods most desired by society. Spurs <span>innovation and the development of new technology. Stimulates business investment and economic growth.<span><body><html>

Original toplevel document

3. ANALYSIS OF REVENUE, COSTS, AND PROFITS
Total variable cost divided by quantity; (TVC ÷ Q) Average total cost (ATC) Total cost divided by quantity; (TC ÷ Q) or (AFC + AVC) Marginal cost (MC) Change in total cost divided by change in quantity; (∆TC ÷ ∆Q) <span>3.1. Profit Maximization In free markets—and even in regulated market economies—profit maximization tends to promote economic welfare and a higher standard of living, and creates wealth for investors. Profit motivates businesses to use resources efficiently and to concentrate on activities in which they have a competitive advantage. Most economists believe that profit maximization promotes allocational efficiency—that resources flow into their highest valued uses. Overall, the functions of profit are as follows: Rewards entrepreneurs for risk taking when pursuing business ventures to satisfy consumer demand. Allocates resources to their most-efficient use; input factors flow from sectors with economic losses to sectors with economic profit, where profit reflects goods most desired by society. Spurs innovation and the development of new technology. Stimulates business investment and economic growth. There are three approaches to calculate the point of profit maximization. First, given that profit is the difference between total revenue and total costs, maximum profit occurs at the output level where this difference is the greatest. Second, maximum profit can also be calculated by comparing revenue and cost for each individual unit of output that is produced and sold. A business increases profit through greater sales as long as per-unit revenue exceeds per-unit cost on the next unit of output sold. Profit maximization takes place at the point where the last individual output unit breaks even. Beyond this point, total profit decreases because the per-unit cost is higher than the per-unit revenue from successive output units. A third approach compares the revenue generated by each resource unit with the cost of that unit. Profit contribution occurs when the revenue from an input unit exceeds its cost. The point of profit maximization is reached when resource units no longer contribute to profit. All three approaches yield the same profit-maximizing quantity of output. (These approaches will be explained in greater detail later.) Because profit is the difference between revenue and cost, an understanding of profit maximization requires that we examine both of those components. Revenue comes from the demand for the firm’s products, and cost comes from the acquisition and utilization of the firm’s inputs in the production of those products. 3.1.1. Total, Average, and Marginal Revenue This section briefly examines demand and revenue in preparation for addressing cost. Unless the firm is a pu







Theoretically, the development of Linguatorium was rooted in the concept of Linguistic Automaton and the cybernetic approach to instruction as regula- tion and control. Linguistic Automaton (Piotrowski, 1999; Piotrowski & Beli- aeva, 2005) is a theoretical framework for creating computational models of the human verbal-mental activity.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




An example of graceful fallback in the context of a vocabulary tutoring system would be a case when the system might not be able to use a lexical unit in certain types of activities due to the lack of semantic information available about the unit, but would still incorporate it into simpler activity types that do not rely on com- putational semantics.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




This functionality provided the infra- structure required for double-blind empirical studies of vocabulary acquisition.

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




In pedagogical research, non-blind randomized controlled trials to date have been the highest standard of evidence-based research design

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




Based on the above, we aimed the present study at answering two research questions. 1. How do automatically generated supplemental activities based on spaced repetition improve vocabulary learning gains in EFL students? 2. Can double-blind experimental design be successfully implemented in a CALL-based pedagogical intervention study?

statusnot read reprioritisations
last reprioritisation on reading queue position [%]
started reading on finished reading on

pdf

cannot see any pdfs




Flashcard 1611517005068

Question
What is the most notable shortcoming of the existing vocabulary learning software?
Answer
“none of the programs is designed to encourage generative use of target words”


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill

pdf

cannot see any pdfs







Flashcard 1611563142412

Tags
#python #scip
Question
What represents the simplest building blocks that a language provides?
Answer
[primitive expressions and statements]


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill
1.2 Elements of Programming
describe a language, we should pay particular attention to the means that the language provides for combining simple ideas to form more complex ideas. Every powerful language has three such mechanisms: primitive expressions and statements , <span>which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units. In programm







Flashcard 1611565501708

Tags
#python #scip
Question
How are compound elements are built from simpler ones?
Answer
[means of combination]


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill
1.2 Elements of Programming
the language provides for combining simple ideas to form more complex ideas. Every powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, <span>means of combination , by which compound elements are built from simpler ones, and means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will disc







Flashcard 1611568909580

Tags
#python #scip
Question
By which means can compound elements be named and manipulated as units?
Answer
[means of abstraction]


statusnot learnedmeasured difficulty37% [default]last interval [days]               
repetition number in this series0memorised on               scheduled repetition               
scheduled repetition interval               last repetition or drill
1.2 Elements of Programming
powerful language has three such mechanisms: primitive expressions and statements , which represent the simplest building blocks that the language provides, means of combination , by which compound elements are built from simpler ones, and <span>means of abstraction , by which compound elements can be named and manipulated as units. In programming, we deal with two kinds of elements: functions and data. (Soon we will discover that they are really not so distinct.) Informally, data is stuff that we want to manipu