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>> help eye

EYE Identity matrix.

EYE(N) is the N-by-N identity matrix.

EYE(M,N) or EYE([M,N]) is an M-by-N matrix with 1's on

the diagonal and zeros elsewhere.

EYE(SIZE(A)) is the same size as A.

EYE with no arguments is the scalar 1.

EYE(M,N,CLASSNAME) or EYE([M,N],CLASSNAME) is an M-by-N matrix with 1's

of class CLASSNAME on the diagonal and zeros elsewhere.

Note: The size inputs M and N should be nonnegative integers.

Negative integers are treated as 0.

Example:

x = eye(2,3,'int8');

See also speye, ones, zeros, rand, randn.

help whos

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WHOS List current variables, long form.

WHOS is a long form of WHO. It lists all the variables in the current

workspace, together with information about their size, bytes, class,

etc.

In a nested function, variables are grouped into those in the nested

function and those in each of the containing functions, each group

separated by a line of dashes. In nested functions and in functions

containing nested functions, even uninitialized variables are l isted.

WHOS GLOBAL lists the variables in the global workspace.

WHOS -FILE FILENAME lists the variables in the specified .MAT file.

WHOS ... VAR1 VAR2 restricts the display to the variables specified.

The wildcard character '*' can be used to display variables that match

a pattern. For instance, WHOS A* finds all variables in the current

workspace that start with A.

WHOS -REGEXP PAT1 PAT2 can be used to display all variables matching

the specified patterns using regular expressions. For more information

on using regular expressions, type "doc regexp" at the command prompt.

Use the functional form of WHOS, such as WHOS('-file',FILE,V1,V2), when

the filename or variable names are stored in strings.

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S = WHOS(...) returns a structure with the fields:

name -- variable name

size -- variable size

bytes -- number of bytes allocated for the array

class -- class of variable

global -- logical indicating whether variable is global

sparse -- logical indicating whether value is sparse

complex -- logical indicating whether value is complex

nesting -- struct with the following two fields:

function -- name of function where variable is defined

level -- nesting level of the function

You must use the functional form of WHOS when there is an output

argument.

>> help who

WHO List current variables.

WHO lists the variables in the current workspace.

In a nested function, variables are grouped into those in the nested

function and those in each of the containing functions. WHO displays

only the variables names, not the function to which each variable

belongs. For this information, use WHOS. In nested functions and

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in functions containing nested functions, even unassigned variables

are listed.

WHOS lists more information about each variable.

WHO GLOBAL and WHOS GLOBAL list the variables in the global workspace.

WHO -FILE FILENAME lists the variables in the specified .MAT file.

S = WHO(...) returns a cell array containing the names of the variables

in the workspace or file. You must use the functional form of WHO when

there is an output argument.

>> who

Your variables are:

a ans m t v w x ys z

>> pwd

ans =

C:\Users\SUKKURIBA\Documents\MATLAB

>> help pwd

PWD Show (print) current working directory.

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PWD displays the current working directory.

S = PWD returns the current directory in the string S.

>> hold

Current plot held

>> help hold

HOLD Hold current graph

HOLD ON holds the current plot and all axis properties so that

subsequent graphing commands add to the existing graph.

HOLD OFF returns to the default mode whereby PLOT commands erase

the previous plots and reset all axis properties before drawing

new plots.

HOLD, by itself, toggles the hold state.

HOLD does not affect axis autoranging properties.

HOLD ALL holds the plot and the current color and linestyle so

that subsequent plotting commands will not reset the color and

linestyle.

HOLD(AX,...) applies the command to the Axes object AX.

Algorithm note:

HOLD ON sets the NextPlot property of the current figure and

axes to "add".

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HOLD OFF sets the NextPlot property of the current axes to

"replace".

FUNCTIONS

>> v=[2 4 7 5], w=[1 3 8 9];

v =

2 4 7 5

>>

>> m=[1 2 3

2 3 1

4 6 5]

m =

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1 2 3

2 3 1

4 6 5

1.>> v(2)

ans =

4

Explanation= here we have taken 2nd element of V variables row.

2.>> sum = v + w

sum =

3 7 15 14

Explanation= here we have added the elements of V and W.

3. >> diff = v -w

diff =

1 1 -1 -4

Explanation=here we have subtracted the elements of V with W.

4. >> vw=[v w]

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vw =

2 4 7 5 1 3 8 9

explanation= here we have set the elements of V and W together.

5.>> vw(2:6)

ans =

4 7 5 1 3

Explanation= here we are taking the elements from 2nd to 6th from the whole row.

6.>> v'

ans =

2

4

7

5

Explanation= here we have inverted the elements of row into column.

7.>> z=[1;1;0;0]

z =

1

1

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0

0

Explanation=here we have created an array of z.

8.>> z'

ans =

1 1 0 0

Explanation=here we have inverted the elements of z from column to row.

9.>> z*v

ans =

2 4 7 5

2 4 7 5

0 0 0 0

0 0 0 0

Explanation=here we have multiplied the whole row of V with each elements of column of z.

10.>> [v ; w]

ans =

2 4 7 5

1 3 8 9

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Explanation=here we have set the elements of V and elements of W together but separating with

(;) for making 1st row of V and 2nd

row for W .

11.>> v*z

ans =

6

Explanation= here we have multiplied elements of v with elements of z ,resultant elements would

be 2 and 4 , 6 is final added result of 2 and 4.

12.>> [z;v']

ans =

1

1

0

0

2

4

7

5

Explanation=here we have kept the column of z with row of v which is inverted to column.

13.>> z+v'

ans =

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3

5

7

5

Explanation= here we have added the elements of column z with column of v which is inverted

form of row v.

14.>> m(1,1)

ans =

1

Explanation=here we have called the elemenys of m which is at first row and first column.

15.>> m(1:2,1:2)

ans =

1 2

2 3

Explanation= here we have called 1st and 2nd row and 1st and 2nd column, by specifieng the rang

with (:) sign.

16.>> m(:,1)

ans =

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1

2

4

Explanation=here we have called all rows anf 1st column of matrix M.

17.>> m(:,end)

ans =

3

1

5

Explamnation=here we are calling the last column with all rows.

18.>> m(:,[1 3])

ans =

1 3

2 1

4 5

Explanation=here we are calling all rows of 1st and 3rd column.

19.>> m(:,:)

ans =

1 2 3

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2 3 1

4 6 5

Explanation= here we are calling all rows and all columns.

20.>> m(:,2)=[]

m =

1 3

2 1

4 5

Explanation= here we have set all rows of 2nd column to null(0r deleted) and showing remaining

column and rows.

21.>> fliplr(m)

ans =

3 1

1 2

5 4

Explanation= here we have flipped the elements of left column to the elements of right column.

>> flipud(m)

ans =

4 5

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2 1

1 3

Explanation= here we have flipped the elements form up to down and down to up.

22.>> m(:)

ans =

1

2

4

3

1

5

Explanation= here we have set values of m in column form by using (:) sign.

>> m=m(:)'

m =

1 2 4 3 1 5

Explanation= here we have inverted the elements of M form column to row.

23.>> diag(v)

ans =

2 0 0 0

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0 4 0 0

0 0 7 0

0 0 0 5

Explanation= here we have set the elements of V in diagonal form.

24.>> diag(m)

ans =

1 0 0 0 0 0

0 2 0 0 0 0

0 0 4 0 0 0

0 0 0 3 0 0

0 0 0 0 1 0

0 0 0 0 0 5

Explanation= here we have set the elements of M in diagonal form.

25.>> a=1:5;

Explanation=here we have set the elements of A ranges from 1 to 5.

26.>> a(2)=6;

Explanation= here we have set the 2nd element of A with value 6.

27.>> a([1 3])=0

a =

0 6 0 4 5

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Explanation= here we set element value of 1st and 3rd column with 0 .

28.>> a(1,2)=100

a =

0 100 0 4 5

Explanation= here we have set the element at 1st row and 2nd column with value 100.

>> a(3)=[]

a =

0 100 4 5

Explanation= here we have set the 3rd column with null value or deleted the 3rd element.

>> a([1 4])=[]

a =

100 4

Explanation= here we have set the values of 1st and 4th column with null value or deleted them.