Ops(3pm) User Contributed Perl Documentation Ops(3pm)
**NAME**

PDL::Ops - Fundamental mathematical operators
**DESCRIPTION**

This module provides the functions used by PDL to overload the basic mathematical operators ("+ - / *" etc.) and functions ("sin sqrt"
etc.)
It also includes the function "log10", which should be a perl function so that we can overload it!
Matrix multiplication (the operator "x") is handled by the module PDL::Primitive.
**SYNOPSIS**

none
**FUNCTIONS**

plus
Signature: (a(); b(); [o]c(); int swap)
add two piddles
$c = plus $a, $b, 0; # explicit call with trailing 0
$c = $a + $b; # overloaded call
$a->inplace->plus($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "+" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
plus does handle bad values. The state of the bad-value flag of the output piddles is unknown.
mult
Signature: (a(); b(); [o]c(); int swap)
multiply two piddles
$c = mult $a, $b, 0; # explicit call with trailing 0
$c = $a * $b; # overloaded call
$a->inplace->mult($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "*" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
mult does handle bad values. The state of the bad-value flag of the output piddles is unknown.
minus
Signature: (a(); b(); [o]c(); int swap)
subtract two piddles
$c = minus $a, $b, 0; # explicit call with trailing 0
$c = $a - $b; # overloaded call
$a->inplace->minus($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "-" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
minus does handle bad values. The state of the bad-value flag of the output piddles is unknown.
divide
Signature: (a(); b(); [o]c(); int swap)
divide two piddles
$c = divide $a, $b, 0; # explicit call with trailing 0
$c = $a / $b; # overloaded call
$a->inplace->divide($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "/" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
divide does handle bad values. The state of the bad-value flag of the output piddles is unknown.
gt
Signature: (a(); b(); [o]c(); int swap)
the binary > (greater than) operation
$c = gt $a, $b, 0; # explicit call with trailing 0
$c = $a > $b; # overloaded call
$a->inplace->gt($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary ">" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
gt does handle bad values. The state of the bad-value flag of the output piddles is unknown.
lt
Signature: (a(); b(); [o]c(); int swap)
the binary < (less than) operation
$c = lt $a, $b, 0; # explicit call with trailing 0
$c = $a < $b; # overloaded call
$a->inplace->lt($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "<" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
lt does handle bad values. The state of the bad-value flag of the output piddles is unknown.
le
Signature: (a(); b(); [o]c(); int swap)
the binary <= (less equal) operation
$c = le $a, $b, 0; # explicit call with trailing 0
$c = $a <= $b; # overloaded call
$a->inplace->le($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "<=" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
le does handle bad values. The state of the bad-value flag of the output piddles is unknown.
ge
Signature: (a(); b(); [o]c(); int swap)
the binary >= (greater equal) operation
$c = ge $a, $b, 0; # explicit call with trailing 0
$c = $a >= $b; # overloaded call
$a->inplace->ge($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary ">=" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
ge does handle bad values. The state of the bad-value flag of the output piddles is unknown.
eq
Signature: (a(); b(); [o]c(); int swap)
binary equal to operation ("==")
$c = eq $a, $b, 0; # explicit call with trailing 0
$c = $a == $b; # overloaded call
$a->inplace->eq($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "==" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
eq does handle bad values. The state of the bad-value flag of the output piddles is unknown.
ne
Signature: (a(); b(); [o]c(); int swap)
binary not equal to operation ("!=")
$c = ne $a, $b, 0; # explicit call with trailing 0
$c = $a != $b; # overloaded call
$a->inplace->ne($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "!=" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
ne does handle bad values. The state of the bad-value flag of the output piddles is unknown.
shiftleft
Signature: (a(); b(); [o]c(); int swap)
leftshift "a$" by $b
$c = shiftleft $a, $b, 0; # explicit call with trailing 0
$c = $a << $b; # overloaded call
$a->inplace->shiftleft($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "<<" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
shiftleft does handle bad values. The state of the bad-value flag of the output piddles is unknown.
shiftright
Signature: (a(); b(); [o]c(); int swap)
leftshift "a$" by $b
$c = shiftright $a, $b, 0; # explicit call with trailing 0
$c = $a >> $b; # overloaded call
$a->inplace->shiftright($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary ">>" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
shiftright does handle bad values. The state of the bad-value flag of the output piddles is unknown.
or2
Signature: (a(); b(); [o]c(); int swap)
binary or of two piddles
$c = or2 $a, $b, 0; # explicit call with trailing 0
$c = $a | $b; # overloaded call
$a->inplace->or2($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "|" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
or2 does handle bad values. The state of the bad-value flag of the output piddles is unknown.
and2
Signature: (a(); b(); [o]c(); int swap)
binary and of two piddles
$c = and2 $a, $b, 0; # explicit call with trailing 0
$c = $a & $b; # overloaded call
$a->inplace->and2($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "&" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
and2 does handle bad values. The state of the bad-value flag of the output piddles is unknown.
xor
Signature: (a(); b(); [o]c(); int swap)
binary exclusive or of two piddles
$c = xor $a, $b, 0; # explicit call with trailing 0
$c = $a ^ $b; # overloaded call
$a->inplace->xor($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "^" operator. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
xor does handle bad values. The state of the bad-value flag of the output piddles is unknown.
bitnot
Signature: (a(); [o]b())
unary bit negation
$b = ~ $a;
$a->inplace->bitnot; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "~" operator/function.
bitnot does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
power
Signature: (a(); b(); [o]c(); int swap)
raise piddle $a to the power "b"
$c = $a->power($b,0); # explicit function call
$c = $a ** $b; # overloaded use
$a->inplace->power($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "**" function. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
power does handle bad values. The state of the bad-value flag of the output piddles is unknown.
atan2
Signature: (a(); b(); [o]c(); int swap)
elementwise "atan2" of two piddles
$c = $a->atan2($b,0); # explicit function call
$c = atan2 $a, $b; # overloaded use
$a->inplace->atan2($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "atan2" function. Note that
when calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This
restriction is expected to go away in future releases.
atan2 does handle bad values. The state of the bad-value flag of the output piddles is unknown.
modulo
Signature: (a(); b(); [o]c(); int swap)
elementwise "modulo" operation
$c = $a->modulo($b,0); # explicit function call
$c = $a % $b; # overloaded use
$a->inplace->modulo($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "%" function. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
modulo does handle bad values. The state of the bad-value flag of the output piddles is unknown.
spaceship
Signature: (a(); b(); [o]c(); int swap)
elementwise "<=>" operation
$c = $a->spaceship($b,0); # explicit function call
$c = $a <=> $b; # overloaded use
$a->inplace->spaceship($b,0); # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the binary "<=>" function. Note that when
calling this function explicitly you need to supply a third argument that should generally be zero (see first example). This restriction
is expected to go away in future releases.
spaceship does handle bad values. The state of the bad-value flag of the output piddles is unknown.
sqrt
Signature: (a(); [o]b())
elementwise square root
$b = sqrt $a;
$a->inplace->sqrt; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "sqrt" operator/function.
sqrt does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
abs
Signature: (a(); [o]b())
elementwise absolute value
$b = abs $a;
$a->inplace->abs; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "abs" operator/function.
abs does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
sin
Signature: (a(); [o]b())
the sin function
$b = sin $a;
$a->inplace->sin; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "sin" operator/function.
sin does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
cos
Signature: (a(); [o]b())
the cos function
$b = cos $a;
$a->inplace->cos; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "cos" operator/function.
cos does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
not
Signature: (a(); [o]b())
the elementwise not operation
$b = ! $a;
$a->inplace->not; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "!" operator/function.
not does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
exp
Signature: (a(); [o]b())
the exponential function
$b = exp $a;
$a->inplace->exp; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "exp" operator/function.
exp does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
log
Signature: (a(); [o]b())
the natural logarithm
$b = log $a;
$a->inplace->log; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "log" operator/function.
log does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
log10
Signature: (a(); [o]b())
the base 10 logarithm
$b = log10 $a;
$a->inplace->log10; # modify $a inplace
It can be made to work inplace with the "$a->inplace" syntax. This function is used to overload the unary "log10" operator/function.
log10 does handle bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
assgn
Signature: (a(); [o]b())
Plain numerical assignment. This is used to implement the ".=" operator
assgn does not process bad values. It will set the bad-value flag of all output piddles if the flag is set for any of the input piddles.
**AUTHOR**

Tuomas J. Lukka (lukka@fas.harvard.edu), Karl Glazebrook (kgb@aaoepp.aao.gov.au), Doug Hunt (dhunt@ucar.edu), Christian Soeller
(c.soeller@auckland.ac.nz), Doug Burke (burke@ifa.hawaii.edu), and Craig DeForest (deforest@boulder.swri.edu).
**perl v5.14.2** 2012-05-30 Ops(3pm)