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# get_d2r

Return a constant that converts degrees to radians. 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_d2r (
val  : numeric or string
)

return_val [scalar] :  float or double
```

## Arguments

val

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

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

## Description

A constant that is used to convert degrees to radians:

```      d2r = PI/180
```

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

## Examples

Example 1: In these examples, the 'd2r' to the left of the assignment can be any name (eg, 'degrees_to_radians', 'deg_ro_rad'). 'd2r'is used for convenience.

```
d2r  = get_d2r("double")   ; type double; 0.0174532925199433
d2r  = get_d2r("float" )   ; type float ; 0.01745329
d2r  = get_d2r("d")        ; type double; 0.0174532925199433
d2r  = get_d2r("f")        ; type float ; 0.01745329

d2r  = get_d2r(1d0)        ; type double
d2r  = get_d2r(1.0)        ; type float
d2r  = get_d2r( 1 )        ; type float

xf   = 2.412
xd   = 2.412d0
xi   = 100

d2r  = get_d2r(xd)         ; type double; same type as '
d2r  = get_d2r(xf)         ; type float
d2r  = get_d2r(xi)         ; type float
```