imat_shp/minus

Purpose

Subtract shape coefficients (s1-s2).

Syntax

s1-s2
s-x
x-s

Description

The following subtraction operations are possible with imat_shp objects:

• Subtracting two imat_shp objects causes their shape coordinates to be subtracted. The shape node numbers must agree between the shapes being subtracted. If one of the operands is a single shape (1x1), then its coefficients will be subtracted from all elements in the other operand. If both operands are shape arrays, they must have the same dimensions. The data attributes of the result of an subtraction operation will be taken from the left operand. A warning will be issued if the ordinate attributes of the two operands are not consistent, but the operation is allowed.

• Subtracting a numeric array or scalar from an imat_shp causes the numeric values to be subtracted from the shape coefficient values of the imat_shp.

• Subtracting an imat_shp from a numeric array or scalar causes the ordinate values of the imat_shp to be subtracted from the numeric values.

Examples

>> s=imat_shp(3,'shape',reshape(1:18,6,3))

s =
3x1 IMAT Shape with the following attributes:
Row Frequency           Damping             NumberNodes
--- ------------------- ------------------- -------------------
1   1                   0.01                2
2   1                   0.01                2
3   1                   0.01                2

>> s.shape

ans =
     1     7    13
     2     8    14
     3     9    15
     4    10    16
     5    11    17
     6    12    18

>> t=s-3;  t.shape

ans =
    -2     4    10
    -1     5    11
     0     6    12
     1     7    13
     2     8    14
     3     9    15

>> t=t-t(1);  t.shape

ans =
     0     6    12
     0     6    12
     0     6    12
     0     6    12
     0     6    12
     0     6    12

>> t=t-[-1 0 3];  t.shape

ans =
    -1     6    15
    -1     6    15
    -1     6    15
    -1     6    15
    -1     6    15
    -1     6    15

>>

See Also

imat_shp/plus