sub

Subtract two fi objects using fimath object

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Syntax

c = sub(F,a,b)

Description

example

c = sub(F,a,b) subtracts fi objects a and b using fimath object F. This is helpful in cases when you want to override the fimath objects of a and b, or if the fimath properties associated with a and b are different. The output of fi object c has no local fimath.

Examples

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Open Live Script
a = fi(pi);
b = fi(exp(1));
F = fimath('SumMode','SpecifyPrecision',...
    'SumWordLength',32,'SumFractionLength',16);
c = sub(F,a,b)
c = 
    0.4233

          DataTypeMode: Fixed-point: binary point scaling
            Signedness: Signed
            WordLength: 32
        FractionLength: 16

c is the 32-bit difference of a and b, with fraction length 16.

Input Arguments

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fimath object to use for subtraction, specified as a fimath object.

Operands, specified as scalars, vectors, matrices, or multidimensional arrays.

a and b must both be fi objects and must have the same dimensions unless one is a scalar. If either a or b is scalar, then c has the dimensions of the nonscalar object.

Data Types: fi
Complex Number Support: Yes

Algorithms

C = sub(F,A,B)
or 
C = F.sub(A,B)

is equivalent to 

A.fimath = F;
B.fimath = F;
C = A - B;
except that the fimath properties of A and B are not modified when you use the functional form.

Extended Capabilities

HDL Code Generation
Generate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.

See Also

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Introduced before R2006a

Fixed-Point Designer Documentation

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