# gsw_t_from_rho_exact

    in-situ temperature from density

## Contents

- USAGE:
- DESCRIPTION:
- INPUT:
- OUTPUT:
- EXAMPLE:
- AUTHOR:
- VERSION NUMBER:
- REFERENCES:

## USAGE:

    [t, t_multiple] = gsw_t_from_rho_exact(rho,SA,p)

## DESCRIPTION:

    Calculates the in-situ temperature of a seawater sample, for given
    values of its density, Absolute Salinity and sea pressure (in dbar).

    Click for a more detailed description of calculating
    in-situ temperature from density.

## INPUT:

    rho  =  density of a seawater sample (e.g. 1026 kg/m^3)       [ kg/m^3 ]
       Note. This input has not had 1000 kg/m^3 subtracted from it.
         That is, it is 'density', not 'density anomaly'.
    SA  =  Absolute Salinity                                        [ g/kg ]
    p   =  sea pressure                                             [ dbar ]
           ( i.e. absolute pressure - 10.1325 dbar )

    rho & SA need to have the same dimensions.
    p may have dimensions 1x1 or Mx1 or 1xN or MxN, where rho & SA are MxN.

## OUTPUT:

    t   =  in-situ temperature (ITS-90)                            [ deg C ]
    t_multiple  =  in-situ temperature (ITS-90)                    [ deg C ]
      Note that at low salinities, in brackish water, there are two possible
        temperatures for a single density.  This programme will output both
        valid solutions.  To see this second solution the user must call the
        programme with two outputs (i.e. [t, t_multiple]), if there is only
        one possible solution and the programme has been called with two
        outputs the second variable will be set to NaN.

## EXAMPLE:

    rho = [1021.8484; 1022.2647; 1024.4207; 1027.7841; 1029.8287; 1031.9916;]
    SA = [34.7118; 34.8915; 35.0256; 34.8472; 34.7366; 34.7324;]
    p =  [     10;      50;     125;     250;     600;    1000;]

    [t, t_multiple] = gsw_t_from_rho_exact(rho,SA,p)

    t =

      28.760866806849798
      28.426820412666761
      22.834628310010174
      10.294318375673690
       6.946306842217355
       4.484889255629902

    t_multiple =

       NaN
       NaN
       NaN
       NaN
       NaN
       NaN

## AUTHOR:

    Trevor McDougall & Paul Barker                      [ help@teos-10.org ]

## VERSION NUMBER:

    3.05 (16th February, 2015)

## REFERENCES:

    IOC, SCOR and IAPSO, 2010: The international thermodynamic equation of
     seawater - 2010: Calculation and use of thermodynamic properties.
     Intergovernmental Oceanographic Commission, Manuals and Guides No. 56,
     UNESCO (English), 196 pp.  Available from the TEOS-10 web site.
      See sections 3.1 and 3.3 of this TEOS-10 Manual.

    The software is available from http://www.TEOS-10.org