Notes-on-Initial-Programming

Description

Notes-on-Initial-Programming

Table of Contents of Brightspace Module

Lecture 1

Lecture 2 (not found)

Lecture 3

Lecture 4

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Lab Week 5

no later content than this on 2023-10-16-at-1529h

Content

Week-6

Lecture-Week-6

Digital Ocean

Let’s look at the available format specifiers available for printf:

%c character

%d decimal (integer) number (base 10)

%e exponential floating-point number

%f floating-point number

%i integer (base 10)

%o octal number (base 8)

%s String

%u unsigned decimal (integer) number

%x number in hexadecimal (base 16)

%t formats date/time

%% print a percent sign

% print a percent sign

ChatGPT3_5

In the System.out.printf method in Java (and similar formatting in other programming languages), the % symbol is used to indicate a placeholder for a value to be inserted into the string being formatted. The characters following % specify the formatting for the value

that will be inserted.

In the example "%9.7f":

% indicates the start of the formatting specifier.

9 specifies the minimum width of the field where the value will be inserted. In this case, it's saying that the minimum width is 9 characters. If the inserted value is less than 9 characters wide, it will be padded with spaces to the left.

.7 specifies the precision for floating-point numbers. It indicates that 7 decimal places should be shown.

f specifies that the value being inserted should be formatted as a floating-point number.

So, in summary, %9.7f is a formatting specifier for a floating-point number with a minimum width of 9 characters and 7 decimal places of precision.

publicclassPrintPi {
publicstaticvoidmain(String[] args) {
doublepiValue = Math.PI;
System.out.printf("Value of PI to 7 dec is %9.7f\n", piValue);
}
}

System.out.printf("Value of PI to 4 dec is %9.4f\n", Math.PI);

System.out.printf("Value of PI to 2 dec is %-9.2f\n", Math.PI);

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W6 Lec PART 2

ASCII Table

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ChatGPT3_5

In Java, you can utilize the Character class to work with characters and perform the mentioned operations. Here's a brief guide on using Character for the specified tasks:

Checking if a Character is a Digit:

java Copy code char ch = '7'; boolean isDigit = Character.isDigit(ch); Checking if a Character is a Letter:

charch = 'A';
booleanisLetter = Character.isLetter(ch);
CheckingifaCharacterisUppercase:

charch = 'C';
booleanisUppercase = Character.isUpperCase(ch);
CheckingifaCharacterisLowercase:

charch = 'd';
booleanisLowercase = Character.isLowerCase(ch);
ConvertingaCharactertoLowercaseorUppercase:

charch = 'A';
charlowercaseCh = Character.toLowerCase(ch);
charuppercaseCh = Character.toUpperCase(ch);
GeneratingaRandomUppercaseLetter:

charrandomUppercase = (char) ('A' + (int) (Math.random() * 26));
ThesefunctionsallowyoutomanipulateanddeterminepropertiesofcharactersinJava. Letmeknowifyouneedfurtherclarificationoradditionalcodeexamples!

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Storing Data (Fixed)

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Storing Data (Dynamic)

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In fixed size rep var point at data

in dyn var point at ref pointing at date

... if change to the date the reference might change....

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Refrerences

Printf

geeksforgeeks Printf

digital ocean Printf

ASCII Table