inv()

Read(495) Label: inv,

Here’s how to use inv() function.

A .inv( p )

Description:

Adjust the order of members of a sequence.

Syntax:

A.inv(p)

Note:

The function adjusts the order of members of A according to the integer sequence p, whose members are ranks of members of sequence A, and return the new A.

If p has duplicate members or has different number of members from A, or the value of a member of p exceeds the maximum sequence number of A’s member, the function will return null. It does not handle the ties.

Parameters:

p

An integer sequence, whose members are ranks of members of A. So the number of its members is the same as that of members of A, and it is a unique n-integer sequence (n is the length of sequence A).

A

A sequence or a record sequence.

Return value:

The adjusted sequence

Example:

 

A

 

1

[b,c,a,d]

 

2

=A1.inv([2,3,1,4])

[a,b,c,d]

3

[b,a,a,c]

 

4

=A3.inv([2,1,1,3])

[a,b,c,null]

 

Related functions:

p.inv(k)

p .inv( k )

Description:

Compute the sequence numbers of an integer’s members in another integer sequence.

Syntax:

p.inv(k)

Note:

The function returns the sequence numbers of the mumbers from 1 to k in integer sequence p. Return 0 for the numbers that do not exist in p.

Parameters:

p

An integer sequence

k

An integer, which is by default the length of p

Return value:

An integer sequence composed of the sequence numbers of the integers from 1 to k in integer sequence p

Example:

 

A

 

1

=[1,3,5,7]

 

2

=A1.inv(4)

Among the four numbers 1, 2, 3 and 4, the sequence numbers of 1 and 3 in sequence A1 are 1 and 2. 2 and 4 do not exist in sequence A1, so their sequence numbers are 0. [1,0,2,0] is returned finally.

Related functions:

A.inv(p)