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get_pi

Return pi as a type float or double.

Available in version 6.4.0 and later.

Prototype

```load "\$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
; from NCL V6.2.0 onward.
; No need for user to explicitly load.

function get_pi (
val
)

return_val [scalar] :  float or double
```

Arguments

val

If val is type numeric, and val is type "double", the returned pi will be type double; otherwise it will be type float.

If val is type string, and val="double" or val="d", the returned pi will be type double; otherwise it will be type float.

If val is any other type, the returned pi will be type float.

It is recommended that the value returned be the same numeric type as the variable(s) with which it will be used.

Return value

The returned scalar pi will be type double or float.

Description

pi is a mathematical constant which is the ratio of a circle's circumference to its diameter.

It is recommended that the value returned by get_pi (get_d2r and get_r2d) be the same numeric type as the variable(s) with which it will be used.

Examples

Example 1: Of course, the name to the left of the assignment statement can be any valid name.

```
PI  = get_pi("double")   ; type double; 3.141592653589793
PI  = get_pi("float" )   ; type float ; 3.141593

pi  = get_pi("d")        ; type double
pi  = get_pi("f")        ; type float

pi  = get_pi(1d0)        ; type double
pi  = get_pi(1.0)        ; type float
pi  = get_pi( 1 )        ; type float

xf   = 2.412
xd   = 2.412d0
xi   = 100

pi  = get_pi(xd)         ; type double
pi  = get_pi(xf)         ; type float
pi  = get_pi(xi)         ; type float
```