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 ordinal number of A’s member, the function will return null. It does not handle the ties.

Parameter:

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:

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 function:

p.inv(k)

p.inv(k )

Description:

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

Syntax:

p.inv(k)

Note:

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

Parameter:

p	An integer sequence
k	An integer, which is by default the length of p

Return value:

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

Related function:

A.inv(p)