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Subsections

ISINF Test for infinities

Usage

Returns true for entries of an array that are infs (i.e., infinities). The usage is

   y = isinf(x)

The result is a logical array of the same size as x, which is true if x is not-a-number, and false otherwise. Note that for complex or dcomplex data types that the result is true if either the real or imaginary parts are infinite.

Example

Suppose we have an array of floats with one element that is inf:

--> a = [1.2 3.4 inf 5]
a = 
  <double>  - size: [1 4]
 
Columns 1 to 2
    1.200000000000000         3.400000000000000      
 
Columns 3 to 4
    inf                       5.000000000000000      
--> isinf(a)
ans = 
  <logical>  - size: [1 4]
 
Columns 1 to 4
 0  0  1  0  
--> b = 3./[2 5 0 3 1]
b = 
  <double>  - size: [1 5]
 
Columns 1 to 2
    1.500000000000000         0.600000000000000      
 
Columns 3 to 4
    inf                       1.000000000000000      
 
Columns 5 to 5
    3.000000000000000



2004-10-09