MyPC-Cabinet: it notes

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Tuesday, March 31, 2015

Data Types in JAVA

Data Types
Premitive	Object
Integers byte (-2⁷ to 2⁷-1) short (-2¹⁵ to 2¹⁵-1) int (2³¹ to 2³¹-1) long (2⁶³ to 2⁶³-1)	(reference data type or array data type) Ex: String
Floating point float (2³¹ to 2³¹-1) double(2⁶³ to 2⁶³-1)
Characters char (0 to 2¹⁶-1)
Boolean boolean(true/false)

Sunday, March 29, 2015

Getting started with JAVA programming

Are you new to java? If yes here is the way to become a java expert. How to install JAVA Development Kit on your computer

Step 1

Download java development kit from oracle.

Click here to download. (Use the images to get an idea)

Click on accept

Select your download type 64 bit or 32 bit

and wait until downlaod complete.

Step 2

After download complete run the setup.

Step 3

Do not change install location and set it to be default

Step 4

Wait until installation to be complete.

Step 5

Now you have JAVA installed in your computer.

Step 6

Then you need to set path to compile a java program. Here is the way.

Go to your java installed location. In my case it may be c:\program files\java\jdk1.7.0\ (may vary due to java version)

create a new folder named “My docs”.

Open that folder.

Now you are inside the folder named “My docs”
Now open notepad and type start and save it as “cmd.bat” in “My docs” folder.

Now go to c:\program files\java\jdk1.7.0\ bin (your may be vary)

Now copy the path in your address bar

if you are a window 8 user follow these steps;

Drag the Mouse pointer to the Right bottom corner of the screen
Click on the Search icon and type: Control Panel
Click on -> Control Panel -> System -> Advanced System Settings
Click on Environment Variables, under System Variables, find PATH, and double click on it.
Now click on variable value field, put a ; at end of the value.
Now paste copied path after the semi colon
click on ok then again ok and ok.

Now go to c:\program files\java\jdk1.7.0\My docs

Now open CMD.bat file

Then type “javac” and press enter

If you get text like in the image below you are successful.

Now it is time to code java.

How to start java coding

Now you can start to code java. Here is an example

Open notepad .Type these text

class a1{

         public static void main(String args[]){

                     System.out.println("Hello JAVA");

        }

}
Now save this as "a1.java" in "My docs" folder.
Now open "CMD.bat" and type javac a1.java and press enter
Then if it was successful type java a1 and press enter.
Now in cmd you can see a text "hello JAVA".
Now do not close cmd keep it minimized and code some more java program.then save it.
Now again type javac and then type name of your saved java program with .java extension .
Then type java and saved java program and press enter.

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RECOMMENDED BY AUTHOR

Data Types in JAVA

Wednesday, February 4, 2015

Use of colors in HTML

we can use RGB colors in web pages to make the page more colorful.
Syntax of RGB color code is rgb(rr,gg,bb)

As an example to show green color using RGB code we can write as following, rgb(0,255,0)

You can get RGB code of a color by using “Adobe Photoshop” or any image processing software. But in HTML we us corresponding hexadecimal value of a RGB color code.
Example : for red color

RGB value = (255,0,0)
Hex value = #ff0000

But most web browsers support 17 main colors.
They are

Aqua
Black
Blue
Fuchsia
Gray
Green
Lime
Maroon
Navy
Olive
Orange
Purple
Red
Sliver
Teal
White
Yellow

we can use them without hex value.
We can use following HTML code
<HTML>
<HEAD>
<TITLE>Colors</TITLE>
</HEAD>
<BODY>
<H1><FONT color=”red”>This is in red color</FONT></H1>
<H2><FONT color=#0000FF >This is in green</FONT></H2>
<P><FONT color=”blue”>This is some text</FONT></P>
</BODY>
</HTML>

The output will be,

How to use background colors.

<HTML>
<HEAD>
<TITLE>Colors</TITLE>
</HEAD>
<BODY BGCOLOR=”orange”>
<H1><FONT color=”red”>This is in red color</FONT></H1>
<H2><FONT color=#0000FF >This is in green</FONT></H2>
<P><FONT color=”blue”>This is some text</FONT></P>
</BODY>
</HTML>

output,

Friday, December 5, 2014

We can align headings to center, left or right. To align ,
<H1 align=”Center”>First heading</H1>

This will align the text “First heading” to center screen of your web browser.

Tuesday, November 18, 2014

Indentation

Indentation in Python

By default python uses 4 spaces per indentation level

Example:>>>def A1( ):

____x=10

____for i in range(1,10,1)

________print i

Spacing and maximum length of a line is 79.

Do not mix Tabs and spaces.

Monday, November 17, 2014

Key Words in Python

Key words are the reserved words that use for specific command.

You can see those key words below.

and	del	form	not	with
as	elif	global	or	while
assert	else	if	pass	yield
break	except	import	print
class	exec	in	return
continue	finally	is	raise
def	for	lambda	try

As python is case sensitive language you should type those keywords in simple letters.

If you are using default settings in python GUI these key words are orange colored or purple colored.

Sunday, November 16, 2014

Introduction & Arithmetic Functions

Introduction to Python

Here we use version 2.7.6.

Let’s take a look at python GUI.

Use of arithmetic and logical expressions.

Order of mathematical operations.

Parentheses : ( )
Power : **
Multiplication,Division : * , /
Addition , Substraction : + , -
XOR : ^

Let’s work with some arithmetic problems.
(you can type an expression in python gui then press enter for the result)

1).2+5 2).5/2 3).9/3 4).9.0/3 5).9.0/3.0 6).2**3+8

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we can use mode function using “%” symbol.

7).5%3 ;(Gives remainder)

N.B. Check out above highlighted ones. They gives different answers.
# is used to indicate comments in python.
You do not need to type those comments.

How to calculate complex arithmetic.

example 1 : 20/7*2.0**/1.5

Steps:

First name the symbols according to their simplification order.
(Refer the order mentioned above)

20/7*2.0**3/1.5

(3) (3) (2) (3)

If you have same order number in many locations number them from left to right.

20/7*2.0**3/1.5

(3) (3) (2) (3)

(1) (2) (3)
Then simplify according to step 1 or if you have to do step to do the calculation from left to right

20/7*2.0**3/1.5

(3) (3) (2)   (3) highlighted one first

(1) (2) (3)

20/7*8.0/1.5

(3)    (3) (3) highlighted one first

  (1)     (2) (3)

2*8.0/1.5

  (3) (3) highlighted one first

   (2)     (3)

16.0/1.5

  (3) highlighted one first

   (3)

10.666666666666666 This is the answer

First try these problems with your mind. Then check out in python gui .

45/6*5-6
5*4*(3+4)+6%4
7.0*5+2**4*(8/5+5*(9%4)-3