AP Computer Science Principles Unit 2 Notes PDF

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Summary

The unit 2 notes compiled from all of the lessons on the Project Stem Advanced Placement Computer Science Principles course in high school....

Description

Claudia Consiglio Mr. Baxter APCSP Unit 2 Notes

2.1

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Algorithm- a process or set of rules to be followed in calculations or other problems solving operations

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Sequencing- logic structure where instructions are executed in order, one after another, one at a time. Often called linear.

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Flowchart- a simple diagram with symbols showing the "flow" of a process

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Flow pattern- pattern that can emerge when data is transformed using computational logic structures (sequencing, selection, iteration).

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Sequential execution- program instructions that are executed one at a time, in specific order.

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A computer can only do what it is programmed to do.

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Scratch uses a lot of sequencing because we have to place blocks one-at-a-time in order.

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Sprite’s state: its location and/or orientation

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Code segment- refers to a collection of program statements that are part of a program.

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Program- a collection of program statements that performs a specific task when run by a

2.2

computer. A program is often referred to as software.

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Parameter- a variable that defines a procedure or sets the conditions of an operation

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Procedure- a named collection of steps in an algorithm that can be reused anytime it is needed without restating the detailed procedures (abstraction)

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Comments- an annotation in the code of a computer program

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Remix- to modify and share a version of an uploaded existing project

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Pseudocode is an efficient way to show your algorithms.

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It is concise and to be precise: regular text can get too wordy and abbreviations can leave

2.3

out important info. 

Want to get to a high-level of extraction: pseudocode.

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A MOD b = remainder of division problem

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Most programming languages follow PEMDAS for order of operations.

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Pseudocode- an informal method of writing algorithmic instructions that do not necessarily follow grammatical rules and syntax of a particular language. "False" code.

2.4 

Selection: if…then

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Sometimes there is a condition that needs to be checked before moving on to the next step.

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Pseudocode doesn’t say THEN, instead uses { }

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There is also if…else: condition is met or is not met.

-Sometimes there needs to be more that 1 possibility in statements with comparisons: if...else…if…else. -Shrink it down to one comparison. 

Operators (text-based) Operator

>

Meaning Greater than

<

Less than

>=

Greater than or equal to...