ii6章-6二维波概述102ii 06 multidim wavesII 06多功能.pdfVIP

ChapterII-6—MultidimensionalWaves

Overview

Chapter

II‐5,

Waves,

concentrated

on

one‐dimensional

waves

consisting

of

a

number

of

rows.

In

Chapter

II‐5,

Waves,

the

rows

were

referred

to

as

“points”

and

the

symbol

p

stood

for

row

number,

which

was

called

“point

number”.

Scaled

row

numbers

were

called

X

values

and

were

represented

by

the

symbol

x.

This

chapter

now

extends

the

concepts

from

Chapter

II‐5,

Waves,

to

allow

waves

having

up

to

four

dimen‐

sions

by

adding

the

column,

layer

and

chunk

dimensions.

The

symbols

q,

r

and

s

stand

for

column,

layer

and

chunk

numbers.

Scaled

column,

layer

and

chunk

numbers

are

called

Y,

Z

and

T

values

and

are

repre‐

sented

by

the

symbols

y,

z

and

t.

We

call

a

two‐dimensional

wave

a

“matrix”;

it

consists

of

rows

(the

first

dimension)

and

columns

(the

second

dimension).

After

two

dimensions

the

terminology

becomes

a

bit

arbitrary.

We

call

the

next

two

dimensions

“layers”

and

“chunks”.

Here

is

a

summary

of

the

terminology:

Dimension

Number0123

Dimension

Namerowcolumnlayerchunk

Dimension

Indexpqrs

Scaled

Dimension

Indext

Historical

Note:

Prior

to

Igor

Pro

3.0,

we

used

the

term

Y

values

to

signify

the

values

stored

in

a

(one‐dimen‐

sional)

wave.

We

now

call

these

“D

values”

or

“data

values”

and

use

the

term

“Y”

for

the

columns

dimen‐

sion.

You

may

find

that

in

places

we

still

refer

to

“Y

values”

when

we

really

mean

data

values.

CreatingMultidimensionalWaves

Multidimensional

waves

can

be

created

using

the

following

extension

to

the

Make

operation:

Make/N=(nrows,ncols,nlayers,nchunks)waveName

The

Redimension

operation

has

been

extended

in

the

same

way.

Examples:

Make/N=20wave1

Makes

a

conventional

(1D)

wave

with

20

points

(rows).

Make/N=(20,3)wave2d

Makes

a

matrix

(2D)

wave

with

20

rows

and

3

columns

for

a