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# functions in cosmo.i - u

 uage ``` univAge(z,q0=,lambda0=) Compute the term to integrate to compute the age of the univers. z can be a VECTOR of values. KEYWORDS: q0 : Deceleration parameter,numeric scalar -a*(a'')/(a')^2 (Omega_m/2-lambda0) lambda0 : Cosmological constant, normalized to th closure density. interpreted function, defined at ./cosmo.i line 133 ``` SEE ALSO: lumdist

 univAge ``` univAge(z,h0=,k=,lambda0=,Omega_m=,q0=,silent=) See IDL routine... PURPOSE: Calculate age of the universe in s EXPLANATION: The luminosity distance in the Friedmann-Robertson-Walker model is taken from Caroll, Press, and Turner (1992, ARAA, 30, 499), p. 511 Uses a closed form (Mattig equation) to compute the distance when the cosmological constant is zero. Otherwise integrates the function using simpson_cosmo. EXAMPLE: Plot the distance of a galaxy in Mpc as a function of redshift out to z = 5.0, assuming the default cosmology (Omega_m=0.3, Lambda = 0.7, H0 = 70 km/s/Mpc) z = span(0,5,50); plg,lumdist(z),z; xytitles,"z","Distance (Mpc)" interpreted function, defined at ./cosmo.i line 215 ``` SEE ALSO: ldist