temperature is converged when thermal.htot and thermal.ctot have a relative
error that is smaller than conv.HeatCoolRelErrorAllowed

conv.HeatCoolRelErrorAllowed is reset with set temperature error command

function lgConvTemp() returns true is heating cooling is converged

conv.lgConvTemp true if converged

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heating cooling arrays

local heating thermal.htot
local cooling thermal.ctot

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heating - main array 
HeatingCom.heating[ipZ][ipZ]
sumed in heatsum
punched in heatpunch.f

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cooling
located in thermal.h
4-char line labels stored in char*5 chCoolants.chClntLab[i]
thermal.collam[i] is the wavelength
thermal.cooling[i] is the actual cooling
thermal.heatnt[i] contains coolant that acutally heats (negative cooling)

CoolAdd - the cooling array is filled with coolants by calling routine CoolAdd by routines that
	do level populations and spectrum

CoolSum - all cooling added together in CoolSum