;+ ; NAME: ; ch4vp ; PURPOSE: (one line) ; Return vapor pressure of CH4 from Brown & Ziegler 1980 ; CATEGORY: ; Volatile Transport ; CALLING SEQUENCE: ; vp = ch4vp(t) ; INPUTS: ; t : temperature, K ; KEYWORD INPUTS ; None ; OUTPUTS: ; vp : vapor pressure in microbar ; OPTIONAL OUTPUT ; None ; RESTRICTIONS: ; PROCEDURE: ; This function implements the tables of Brown and Zeigler ; MODIFICATION HISTORY: ; Written 2013 Jun 13, by Leslie Young, SwRI ;- function ch4vp, t if isarray(t) then begin p = 0. * t for i = 0, n_elements(p)-1 do p[i] = ch4vp(t[i]) return, p endif ; Return vapor pressure, in microbar, as a function of temperature a=[1.71271658e1, -1.11039009e3, -4.34060967e3, 1.03503576e5, -7.91001903e5] p = exp( total((t^(-findgen(5))) * a))* 1.33322e3 return, p end